• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

dbx 1231 Graphic EQ Review

Joined
Nov 29, 2020
Messages
72
Likes
76
I almost hate to mention this....a Q-Sys Core110f running QSys Designer software ..... because i hear supply chain issues have disrupted new deliveries out to Q1 2023, and used 110f's have been selling above the list price at $3300. Pre covid, $1250 or so was all anybody had to pay on ebay, with a little patience.
But despite current supply/price issues, i believe it helps to be aware of options like QSys, as I think this is where the DSP market may be heading.

Anyway...QSys is open architecture design. You draw up a schematic on a PC/MAC using QSys Designer, and then the software compiles the schematic into Linux running on the hardware Core110f.

Equalizer capability now.....

graphic:
The Graphic Equalizer provides from 6 bands with 2 octaves per band up to 61 bands with 1/6th octave per band. Each band can be adjusted from -20dB to +20 dB.

flat top graphic parametric:
same band capacity as graphic
(I'll contrast these two types of graphic in a minute...

parametric:
The Parametric Equalizer is a variable equalizer allowing you to individually adjust the Gain, Bandwidth and center Frequency of up to 32 frequency bands. You can also Bypass individual bands. Master controls, affecting all bands, include Bypass, Invert, Mute and Gain. Additionally, you can change any or all of the bands to either a high or low-shelf equalizer.

flat top parametric:
same band capacity as parametric
(will contrast the two parametrics too)

Any of these EQs can have multiple instances in the design schematic. Iow, you can have a bank for varying track tonality, and another one for room EQ, etc.
Each EQ can be mono, stereo, or multichannel.



Ok, here's a screenshot of graphic vs flattop graphic.
I chose 16 two-thirds oct bands for a simple view.....(61 1/6th oct bands makes for one wide screen lol)

Same eqs setting are in both.
Note how the flattop gets rid of the ripple in adjacent bands. And how the phase shift is a bit more gentle.
It's not a big deal, but cool to have i guess.

View attachment 220256


Ok again, now parametric vs flattop para.....this one is more interesting imo....

Settings are not the same, because the two are not trying to do the same task, like in the graphic.
The Parametric is just to show the settings block. Note you can use either BW or Q, which are linked together. Up to 32 bands.

The flattop allows each side of the EQ to have its slope set independently of the other side.
A couple of examples are shown, an asymmetric at 420Hz, and a symmetric flat top at 3.6kHz.

I've found the flattop para works very well for quasi-anechoic speaker tuning like the 420Hz example, and also for tone control when used flattop and shallow side slopes.


View attachment 220259


Saved the best for last :)

Any control from the design schematic, from simple overall volume to any of these EQ settings, can be placed onto a control screen on a Win or OS device, that is connected to same network as the Core 110f . You can put any remote control you want on an Iphone for example. And customize the appearance/action of the control element.

I use a touchscreen PC.
Admittedly touch screen faders and knobs are not as much joy to use (for me) as real faders and knobs,
but it's kind amazing how many live sound guys are now mixing shows on tablets controlling their mixer...so i know it's mainly a matter of habit....

Hope this was interesting and not OffT...
I’ve got a 110f in my “demo” system. Using it as a massive ADC to convert the analog ATMOS outputs of a Maestro X7 into AES67 and routed to my amps. (Among other things.]
 

Scrappy

Active Member
Joined
Aug 4, 2022
Messages
219
Likes
184
Yup. If you’ve got a good / trained ear then having a decent GEQ in the signal chain for stage monitors can really save your a$$.
“String ‘em and ring ‘em” as I say, ha. Tonality EQ should be done on dedicated monitor channels. Hopefully you don’t have to correct for bad boxes with buss parametrics. But then you may need to apply up to ~6 cuts on the graphic. Gain is gain, and if 1/3+ of the bands are at minus 3-8dB, EQ is just eating gain, no improvement.
 

Sir Sanders Zingmore

Addicted to Fun and Learning
Forum Donor
Joined
May 20, 2018
Messages
947
Likes
1,898
Location
Melbourne, Australia
Linear phase EQ only compensates by adding delay to offset. The initial phase issues are still there.
I’m not sure I follow. When you say the “ initial phase issues” do you mean the issues introduced by EQ or issues that were there prior to EQ (sorry for the basic questions)
 

gnarly

Addicted to Fun and Learning
Joined
Jun 15, 2021
Messages
988
Likes
1,390
I’ve got a 110f in my “demo” system. Using it as a massive ADC to convert the analog ATMOS outputs of a Maestro X7 into AES67 and routed to my amps. (Among other things.]
Interesting use. Amazing what all Q-Sys can do, huh?
I'm using a 110f to convert my PC's USB into Core-to-Core streaming to a 500i, which runs a LCR setup of 5-way speakers. (I use the 500i just for a lot of FIR capability.)
 

Zinda

Member
Joined
Apr 30, 2022
Messages
19
Likes
3
I've tried my share of EQs in my time and I have tried a few DBX EQs and crossovers, one similar to this in 2 versions. I found them to be better sounding with less noise than any cheap home stereo EQs without any compare.

But they feel cheap when using and the sliders themself are so cheaply made it's embarrassing.
Amir is very correct saying finding zero is a challenge is being nice. The sliders center detent is either so strong that you end up moving others while trying to get it to move and others seem to have no detent at all and it becomes impossible to know where you are. Get 4 in a row with weak center and you'll drift away from center as you move.

1 thing I also did not like was the gains did not go completely down to zero. They can't be used as a pre as others can. The last thing I found the sliders loosen and lose connection unless shimmed to one side. 2 of mine quit entirely and upon inspection saw how the sliders are made.

For those of you that are unfamiliar with Samsung's design dept works, they are either allergic to metal or carry a hatred for it. They excell in their plastics, finding ways to make things traditionally made from metal (lasting a lifetime) and developing an all plastic replacement (purposely made to last 3 years).

I have found a dual 31 band EQ that has full volume controls and has a much better slider, the one I have also has a subwoofer output separate that can be disengaged, I have no use for it since I have a 3 way active crossover for my 2 way speakers. This allows overlap at the crossover point. When everyone is trying to get the sharpest slopes (like those offered in digital EQs) I have found the ideal way to go is to work with the rolloff and lap. This makes it impossible to hear the transfer from driver to driver, the EQ helps to keep the transfer smooth just before and after the crossover point. All EQ is done before the crossover and I find little need to correct after.

I have gone down the digital EQs route foolishly thinking I could replace both EQ and crossover with some cheap digital device. It was quite a learning experience that kept on showing me exactly just how awful things can sound.

I tried MiniDSP, both Beringer digital EQ and Crossovers (DEQ & DEX 2496 I think) and a Brazilian DSP. After days with the DSP I gave up, the sound was immediately degraded the moment I connected it and once I changed any EQ settings I lost all of the realism in the sound. The Beringer stuff is far too limited on what you can do. It runs out of processing or memory before you can do anything and it cannot be expanded. I also noticed a huge loss in accuracy and realism in the sound. The Brazilian had a bad channel.

I spent a few months with the Beringer stuff and found it much easier to use than the MiniDSP. I also would never use my computer as a source or for anything that has to do with music since I can hear the 1100watt power supply switching noise in my electrostatic panels the second I turn it on. That happens without even connecting the comp to my audio system! I've tried setting gains and found cannot be stopped without modifying the AC input. I'm convinced all computers inject some interference.

The best way to test an EQ is to set all gains at max then turn up the gains while no input is connected. You'll hear exactly how it affects your system this test works on both digital and analog. The thing you'll need to do with digital is use shelf filters or you'll likely run out of prosessing or memory, you'll hear exactly just how silent digital is, don't forget to max the gains too! I found out that not much has really changed since 1999 when I was building a competition car system and was looking at digital EQs and went with 2x mono 31 band audio controls and a 4 way analog crossover. The digital interface was slow and changing a simple setting was tedious.

Adding more functions hasn't helped the interface on digital and forcing the use of a computer is even worse than hitting a million buttons to add 1 db to a frequency but finding out neither have room left in memory or processing to do it once you finally found it.

I'm using an OSP EQX 231A. It really resembles the DBX model numbers but I can reassure you they are very different once you see the insides. The OSP uses boards with components soldered to it in through hole design. No surface mount chips but uses point to point wiring to connect boards to power supply and even on board in some places but has far superior sliders than DBX, absolutely noise free when moving. It's also my pre to a Beringer CX3400 that controls 2x QSC 3500 amps, system is silent and very flat. I know I'd hear any hiss with 14 electrostaic panels per side.

I think this test has no merit, without moving any sliders you have essentially shown what somebody will have if they put an EQ in a system for no reason other than to have one. If not to act as the pre (which this cannot) it has no use until it starts to do any correcting. Think a parametric EQ will be given the same tests and then be recommended? One thing I can say is when I make an adjustment at a frequency that exact frequency is centered on the RTA display and ONLY at that frequency! This is something that digital was proven to fail. Moving a frequency will also affect other frequencies 1 or 2 octaves away in a lesser amount.
 

anmpr1

Major Contributor
Forum Donor
Joined
Oct 11, 2018
Messages
3,721
Likes
6,405
1) But they feel cheap when using and the sliders themself are so cheaply made it's embarrassing.

2) For those of you that are unfamiliar with Samsung's design dept works, they are either allergic to metal or carry a hatred for it. 3) They excell in their plastics, finding ways to make things traditionally made from metal (lasting a lifetime) and developing an all plastic replacement (purposely made to last 3 years).

4) The best way to test an EQ is to set all gains at max then turn up the gains while no input is connected.

1) It is a cheap device. How is it embarrassing at it's price point? Is there another EQ at the same price that is appreciably better, and therefore not embarrassing?

2) It is unfair to Samsung to single them out. Can you name a company that makes inexpensive products that do not use a lot of plastic? In fact, the only plastic on the user controls are the input gain knob covers, and the clear LED push buttons. Both the front panel, side panel, top and back panel, and sliders are aluminum.

3) No product using switches, knobs, sliders, and buttons, even if constructed out of metal, is going to 'last a lifetime'. Of course it depends on whose life you are referencing, and how long the person is expected to live.

4) Can you clarify your procedure? By 'all gains' do you mean the frequency sliders, and by 'turn up the gains' do you mean the rotary input gain knob, and exactly what does 'no input is connected' refer to--running the EQ directly into the amplifier without being connected to the preamplifier, or signal source?
 

Zinda

Member
Joined
Apr 30, 2022
Messages
19
Likes
3
1) It is a cheap device. How is it embarrassing at it's price point? Is there another EQ at the same price that is appreciably better, and therefore not embarrassing?

2) It is unfair to Samsung to single them out. Can you name a company that makes inexpensive products that do not use a lot of plastic? In fact, the only plastic on the user controls are the input gain knob covers, and the clear LED push buttons. Both the front panel, side panel, top and back panel, and sliders are aluminum.

3) No product using switches, knobs, sliders, and buttons, even if constructed out of metal, is going to 'last a lifetime'. Of course it depends on whose life you are referencing, and how long the person is expected to live.

4) Can you clarify your procedure? By 'all gains' do you mean the frequency sliders, and by 'turn up the gains' do you mean the rotary input gain knob, and exactly what does 'no input is connected' refer to--running the EQ directly into the amplifier without being connected to the preamplifier, or signal source?
I have used a few EQs that are considerably less money and we're of comparable quality, the alesis 30 band comes to mind, priced under $80!
Although it's cheaper it comes with its own used issues, like DBX having a weak center detent, it's the opposite, such a strong detent that moving them from zero tends to be a 2 handed job. Plus the size of it and weight are less, you have to hold it if it's not mounted in a rack. Rack mounting will remove most of the negative used issues. Plus it uses an external ac power supply, removing any sheilding issues. The sliders are similar plastic but feel much tighter.

The OSP I'm currently using has a thick front plate and heavy steel cabinet, real compinents, lots of full sized components and 2 separate boards, I did add a sheild that covers much more of the power supply from the lower board while I had the cover off. I did that before I even tested it, so I can't say if it had noise, I just know that not having any sheild is not a good thing in most cases. The best feature is the volume controls go to zero output which allows it to be used as a pre amp! It would be perfect if it had a second input which most older big name EQs have. The OSP has an adjustable sub woofer output which I don't use but could be a huge plus for those who add on a subwoofer to their system.

Now I have to say that my Samsung conclusion is based on my working on many Samsung devices over the years. They have been the leaders of making things cheaper and using the least amount of metal on their products. They use the thinnest ribbon cables known to exist. You unplug it and you're likely to never get it back in. The ends will tear off or the coating peeks back flaring the thinnest metal traces, folding them back and shorting out. I have opened far more Samsung products that need repair than any other maker. They make their products to last only a few years before they fail. I have so much bad to say about Samsung you'd be better off to not even bring this up with me. I personally would never buy their products for my own use due to their design practices. Their lasers last 3 years before they stop reading, amp and powesupply boards have the thinnest cooper traces that peel off when you try to remove their junk components from the board. I quit working on their junk. Just wait till you start seeing all plastic speakers that use metal coated plastic for wires. If they can figure it out, they'll use it!

If you constantly use those switches and sliders made from metal they will tend to last for decades. The problem only comes in when they remain dorment. You know this and bringing it up to try and make it sound like I'm just making things up is absurd. I have 8 EQs here right now and the only one with a problem is the DBX. I have an Alesis 2x 30 band, Audio Control 4 or 5 band (I'm too lazy to go dig it out to check the model number right now), 2x ADC soundshapers (1 with 2x10 bands and 1 with 2x 15 bands), 2 sansui one has 2x 15 bands and a spectrum screen the other is a cheap dual 8 band), Azden Q50 I think, it has 2x 15 bands and has built in pink noise and pure tones with a mic input for correction. The OSD and DBX, plus all of those I have owned over the years and sold. None have ever been noisy or had bad faders but the DBX. I've owned many DJ mixers that have 1 slider that gets abused constantly and even 20 years old those metal sliders still work flawlessly. I'm talking very cheap Gemini or Beringer or Radio Shack stuff.

I think the max out test is obvious, sliding all bands to max will tell you everything you need to know about noise. Very few graphic EQs (even digital) can be maxed and stay quiet. Once you crank the gain up you'll not believe just how awful most EQs are. I have another gain on my active crossover to set as well as each output has a gain control, my amps have another gain for each channel so it's easy to find out exactly how noisy any piece is. I'll toss this one out there as well since I read a ton of negative stuff on the web bashing BBE maximizers, I have an d 422A and it's silent, I never move the controls from zero unless the recording is lacking highs, then 1 click is all it needs. A good recording nulls the BBE from doing anything but phase correction, turning it off and on has a very slight mid correction quality that's addictive. With my speaker and amp configuration I'm able to hear everything very clear and if there is anything causing noise or distortion you'll hear it. Ear close to electrostatic panels yeilds no audible sound running zero info tracks at typical volume levels.

When I chime in, it only will happen when there's something I'm familiar with. I'm not here to start any problems. Half of the tests I see here I don't even understand, others I see little use to even bother running. I can tell in a few minutes after flipping the switch if something is junk or not.

I don't rate any other way, everything needs to be connected to a real speaker before I can judge it. It's best to use a speaker you know will dip down to 2 ohms when testing, this weeds out those amps you could harm without even knowing. Quality stuff comes in all shapes, sizes and cost, some components might not appear to be what you think, others, as I have found, get consistently good praise while never impressing me, especially when they carry huge price tags.

New gear rarely seems worth the price when the gains are inaudible or worse, they can't even match the sound of older gear costing far less. Let's face it, this hobby is loaded with false reports, false reviews, confusing double talk with new terms and new findings that end up being untrue or make little to no difference in the end. I can't even count how many times I've read about the next big thing, subwoofers mounted on the sides of cabinets, coax drivers, metal dome tweeters, speakers that cost more just because they use more woofers and still can't actually reproduce low tones for sh1t.

Now it's all about beryllium tweeters, multiple tiny drivers, and to get people to buy it, the constant new findings and new standards set by a few who know all. Stupid test programs that are supposed to show you everything you need to know but no 2 will ever show the same results. Huge concerns over phase, lobing, floor bounce, decay, time alignment, reflection, refraction, wife approval, room modes, sound traps, on and on. The best thing is alm these terms seem to be based on these test programs that use a microphone that's the same exact one used in a $25 cell phone but they'll charge you up to $1000 and people buy it. I have a pile of microphones and tons of phones. Each one shows different results, some claim to be calibrated, run the same mic on different programs and get different results, my last $25 phone has a better mic than the last Dayton mic that cost more than the phone.

People are easily fooled and always worry about what others think, good, bad, ugly, big, small, subwoofers, digital correction, it comes down to making your own speakers or paying huge $ to get something that's just a fancy cabinet filled with drivers available from Parts Express. Go with an active crossover and you'll find a fast and inexpensive alternative to paying huge $ for a decent sounding set of speakers. There's lots of good used equipment that can put you in sonic heaven, I wouldn't suggest building an amp when there's so many for cheap available, bug I doubt you'll ever get there using a premanufactured speaker that costs under $10k.

These are my own views, I have no affiliation with any audio manufacturers and only dislike 1 brand, you can do whatever you want since it's your $ and time. I bass my thoughts on what I've personally experienced and have realized exactly why I couldn't find that realistic sound I desired until I pieced together my own speakers. I believe many will agree that you're spinning your wheels buying popular speakers that sell for less than $10k, if you have the cash to burn then you're set. If you think $10k is way to much for speakers but aren't willing to research making your own, good luck. Forget all the newest catch terms that are injected into these forums, forget what others say are great until you hear them for yourself, just being better than what you have is not worth buying, once you hear the sound that captivates you and makes you get chills, you'll hear things that make you turn and look to the side from hearing sounds that sound so real like it came from the walls or behind you but in perfect form, you'll know you are on your way to audio nervana. One last thing, I found a 2 way speaker (1 crossover point under 1000Hz) with each driver or group of drivers getting its own channel can cover the entire spectrum of usable sound, if 1 speaker could do it, I'd recommend it but it doesn't exist yet. Single driver speakers are what the audio industry needs to focus on, anything else is not even trying and a waste of time.
 

anmpr1

Major Contributor
Forum Donor
Joined
Oct 11, 2018
Messages
3,721
Likes
6,405
1) I have used a few EQs that are considerably less money and we're of comparable quality, the alesis 30 band comes to mind, priced under $80! 2) ...like DBX having a weak center detent, it's the opposite, such a strong detent that moving them from zero tends to be a 2 handed job. Plus the size of it and weight are less, you have to hold it if it's not mounted in a rack.

3) Now I have to say that my Samsung conclusion is based on my working on many Samsung devices over the years. They have been the leaders of making things cheaper...

4) If you constantly use those switches and sliders made from metal they will tend to last for decades. The problem only comes in when they remain dorment. You know this and bringing it up to try and make it sound like I'm just making things up... 5) None have ever been noisy or had bad faders

6) I think the max out test is obvious, sliding all bands to max will tell you everything you need to know about noise.

7) When I chime in, it only will happen when there's something I'm familiar with. I'm not here to start any problems.
1) Alesis does not sell a dual channel, 31 band EQ. Or, at least according to their Website, any EQ. So again, I ask, where else are you going to find an EQ with the features of the dbx, for its price?

2) Two hands? To move the sliders? One to hold down the unit, and the other to move the slider? Not on my unit. And it's not in a rack. I think knobs would be a better interface for an analog EQ--from an ease of adjusting standpoint. But you don't find them at this price point. Probably because of the practical visual aspect--that is, quickly looking at the front in order to determine FR position.

The center detent certainly doesn't 'grab you', but it is easily found, haptically. It could be better in this regard.

3) Samsung is certainly in the forefront of manufacturing things cheaper and lighter. But they are not the only company. From my experience, Samsung products are no different than any other company, at a given price point. But without knowing initial build specs to the OEM, return rates, warranty claims etc., it is impossible to know. Your anecdote is surely as good as mine. Or anyone else's.

4) Yeah...it's usually not the sliders or knobs, or buttons, or switches that cause problems. It's what they are connected to. Electrical contacts often go bad, needing cleaning or replacing. On any component. Expensive to cheap. BTW, I wouldn't accuse you of making things up. Don't take this stuff personally. You won't sleep well at night if you do that. (See my last comment, below.)

5) None of your other EQ have ever had noise issues? None?

6) It wasn't obvious to me. That is why I asked. Of course an analog EQ will give audible noise if gain is jacked up. No one doubts that. But who uses their EQ with all the positions maxed? Or even one or two? Who does that?

Inserted between a DAC3HGC and AHB2 (in an analog path) I have to turn the gain of the preamp up to about 2PM to hear EQ noise, standing next to my loudspeaker. I can tell you for sure that long before that happens, with a music signal, I'm out of the house. So the question for anyone considering this device, is whether its negatives are less obnoxious than its positive attributes. Of course it would be better not to ever use something as prole as a dbx in a Benchmark chain, but until John decides to sell a matching EQ for a few hundred dollars...

Also, consider what and who this device is intended for. I doubt you would see it in a recording facility, where budgets are less limited, and where ultimate fidelity is a requirement.

7) I certainly didn't think you were out to cause problems. Again, don't take this stuff personally. You never want to do that.

One thing: in my analog path the device is 'set it and forget it'. If I need digital EQ, then that can be done in software. I am perfectly happy to admit that if someone has to frequently use the sliders, moving them up and down on a daily basis, then YMMV.
 

anmpr1

Major Contributor
Forum Donor
Joined
Oct 11, 2018
Messages
3,721
Likes
6,405
Isn't it designed for different professional studios?
It's a pro-oriented product. But it would surprise me if you found one where ultimate fidelity is important, and where budgets are unrestricted. Most of that is likely done digitally, in any case. For home studio, or on location, in an analog situation, and for the price, these are good value if you need what they offer.

One thing--I'm pretty sure that the EQ bypass just makes the signal flat. The active components remain in the signal path, and are not bypassed. If you use @Zinda little experiment, turning the sliders up to max, and then switching the EQ in and out, noise remains about the same. A little less, but it's not a straight line bypass.

As I speculated, we find a handful of companies selling pretty much the same product, with the same features, and almost same front panel layout. My guess is that they are all made by the same OEM, and then branded. But it's just a guess. Maybe similarities are just coincidence?
 

Zinda

Member
Joined
Apr 30, 2022
Messages
19
Likes
3
1) Alesis does not sell a dual channel, 31 band EQ. Or, at least according to their Website, any EQ. So again, I ask, where else are you going to find an EQ with the features of the dbx, for its price?

2) Two hands? To move the sliders? One to hold down the unit, and the other to move the slider? Not on my unit. And it's not in a rack. I think knobs would be a better interface for an analog EQ--from an ease of adjusting standpoint. But you don't find them at this price point. Probably because of the practical visual aspect--that is, quickly looking at the front in order to determine FR position.

The center detent certainly doesn't 'grab you', but it is easily found, haptically. It could be better in this regard.

3) Samsung is certainly in the forefront of manufacturing things cheaper and lighter. But they are not the only company. From my experience, Samsung products are no different than any other company, at a given price point. But without knowing initial build specs to the OEM, return rates, warranty claims etc., it is impossible to know. Your anecdote is surely as good as mine. Or anyone else's.

4) Yeah...it's usually not the sliders or knobs, or buttons, or switches that cause problems. It's what they are connected to. Electrical contacts often go bad, needing cleaning or replacing. On any component. Expensive to cheap. BTW, I wouldn't accuse you of making things up. Don't take this stuff personally. You won't sleep well at night if you do that. (See my last comment, below.)

5) None of your other EQ have ever had noise issues? None?

6) It wasn't obvious to me. That is why I asked. Of course an analog EQ will give audible noise if gain is jacked up. No one doubts that. But who uses their EQ with all the positions maxed? Or even one or two? Who does that?

Inserted between a DAC3HGC and AHB2 (in an analog path) I have to turn the gain of the preamp up to about 2PM to hear EQ noise, standing next to my loudspeaker. I can tell you for sure that long before that happens, with a music signal, I'm out of the house. So the question for anyone considering this device, is whether its negatives are less obnoxious than its positive attributes. Of course it would be better not to ever use something as prole as a dbx in a Benchmark chain, but until John decides to sell a matching EQ for a few hundred dollars...

Also, consider what and who this device is intended for. I doubt you would see it in a recording facility, where budgets are less limited, and where ultimate fidelity is a requirement.

7) I certainly didn't think you were out to cause problems. Again, don't take this stuff personally. You never want to do that.

One thing: in my analog path the device is 'set it and forget it'. If I need digital EQ, then that can be done in software. I am perfectly happy to admit that if someone has to frequently use the sliders, moving them up and down on a daily basis, then YMMV.
Alesis as some others make a dual 30 band eq, it uses the exact same bands as a 31 band but removed the lowest 20Hz band. So technically it's doing the same job.

I own one of all these I mentioned and it seems like you don't believe me when I say it needs to be held down to move the sliders from zero, obviously I'm talking about when it's not mounted in a rack!

You must be "Mr. Stickler" the guy who looks for the tiniest thing to try and make a point of it. I can see if I was lying or made an error for real but it appears that you have a problem with the info I have provided.

What about my statement about how to really test an eqs worth by moving all sliders to full gain and then increase the overall input gain to hear how much noise could be introduced? I realize that it's not practical to set an eq like that but then again that's not how audio testing is done. You don't only perform tests based on probable use to find noise, I would never crank my amps up even close to max output, but yet every test will include that or someone here would be bitching about how that test is missing? Well that's me on this test, im wondering why it wasn't done?

I have never owned an eq (I have 3 right now from the early 1980s) that made any switch noises or slider noises in my entire life. I have owned, fixed and sold a bunch of noisy receivers, never had any porblems with a pre amp making those same noises not even an old Hafler system I just sold. My old NAD or Rotel receivers were noise free as well. I do believe that it depends on the quality of those devices used that will determine the noise they will make over time.

I'm not just making shit up to disagree or cause a problem, I come here and check out what results are for things I see available and I've found that the test results are not where I get my info, the real good info lies in the comments that proceed the tests.

Many smart people here know the right questions to ask to make sure the testing is fair and the results are accurately posted. This works both ways, I trust Amir and his testing abi!ity, I have REW on my comp but have found it to have no value to me and I'm not going to bother getting it set up when I can't trust anything it plots. None of it can be trusted without a known calibrated piece of equipment being there to confirm all output from all tests. I would say that there should be 2 other programs that also provide the exact same results to further confirm the results to be true. But that would only cover those ranges being tested and a program can change as new settings are made and without a 2nd tool used in tandem over a wide range of settings, there's no way to be sure.

That's why an oscilloscope needs to be checking each test, I'm sure that most everyone knows that the results from 75% of these tests can be done on a scope and if that scope is calibrated, it can be trusted to be accurate. What programs have done is made the testing less complicated and messy to perform, they also show results in a way that can be easily read, saved and compared. You'd be snapping shots of a tiny scope screen that uses moving light traces and are difficult to capture without long exposure shots and some filtering. Plus you lose the nice clear lines and the units of measure across each plane would need to be clarified. You get what I mean. Before the programs were popular you didn't see these results posted often unless a reputable magazine would run them and post them but they were careful of what was included and it was followed up with real world listening to verify if those readings had any value or showed up in the real world.

When you start throwing terms around and acting like they have a huge meaning to the person listening to music or a movie and those terms are rarely part of any testing, blaming the fact that each room is different and requires individual testing to really know the actual value. (Reflection, refraction, floor bounce (my favorite, I've tested this several times by moving my woofers closer and further from the floor with no changes, tests made for this simply don't work and give random unrepeatable results), lobing (another good one), room modes, ect... all there to give people something to worry about.

Even so, how can anyone trust a phone mic or even any calibrated mics available? I know I get 12 different results from 3 phones, 1 tablet and 2 calibrated mics. Each phone shows vastly different plots, then each mic connected to that same phone shows 2 more different plots, with 4 devices and 16 results I'm not able to overlay any of them and see any matching plots. Some are so different it looks like they had to be a mistake. But that's not the case since I run 5 or 6 of the exact same tests on each device for each mic and I only accept the results that I can see are nearly exact before I screen shot it for examining later.

One step further, the microphones used in phones are no different than the bogus cheap calibrated mics that cost more than my cheap spare phone which I have found to be more accurate than the calibrated mic from Dayton. It cost me close to $30 and the phone cost $25 and the mic is just a tiny part of the phone but is far better than the mic made exclusively for testing?

Next thing to consider, I can use 1 device, 1 mic, 1 app and I can get exact same repeatable results, change the app, I get completely different results and some apps can't even produce 2 exact same results ever. So how can I trust any of them when I have no real calibrated testing equipment to verify which combination is actually showing the correct results?

I'm not going to return to argue my point. When I used DSPs I figured out just how awful they sound and I didn't even bother trying to use them for anything since i knew they would never remain connected. If anyone using a DSP cannot hear the degrading of the sound then their system isn't quite up to par yet, if you think your system sounds better using a DSP, then I would suggest looking into some new speakers first or repairing what you have, it you still can't hear the change, I'd consider a new amp or repairing the one you have with fresh caps.

Most users aren't going to hear the DSP stripping away the tiniest transients since their equipment and/or speakers are unable to deliver that resolution. DSP makers are counting on that, really aiming for the AV community since it's been part of that group for decades now. Not a whole lot of acceptance with home preamps or high end 2 channel receivers, that should speak volumes. Keep in mind that I'm not concerned with what a DSP will add (noise or anything isn't my concern so testing them makes no difference) it's what they take away, they may be silent and pass all tests wonderfully, we all know that tests can't show you the way things actually sound at the speakers.

.
 
D

Deleted member 52288

Guest
Hey, kinda going back on track to EQ stuff. Do you think it would be a "cleaner" operation of the analog EQ to do cutting only? Maybe start with everything in the middle of the sliders/knobs and only lower the things that you need to be lowered? I would imagine (and I could be very wrong) that raising a certain frequency band would be more difficult (read noisy) than it would be to just lower it. I think the downside would be that you might need some extra volume if you were cutting a large portion of the audible band but volume is usually the thing we have plenty to spare and for headphones, it is usually pretty clean to go into the higher ranges without as much distortion.
 

Hapo

Senior Member
Joined
Jan 11, 2022
Messages
464
Likes
320
...do you think the 15-band version will be a clean sonically...???...
 

witwald

Senior Member
Forum Donor
Joined
Jul 23, 2019
Messages
478
Likes
502
...do you think the 15-band version will be a clean sonically...???...
I suppose you a referring to the dbx 1215 Dual Channel 15-Band Equalizer. Did you have any particular areas of concern?

The dbx 1215 could be reasonably expected to be equally as sonically clean as the dbx 1231. As it's probably based quite closely on the dbx 1231, I wouldn't expect to see any substantial differences in performance characteristics (apart from the 2/3 octave bands, of course).
 

Hapo

Senior Member
Joined
Jan 11, 2022
Messages
464
Likes
320
...thanks...I just wanted to see if I was the only one who though that...

...I don't hear much above 8k anyway, so the lack of coverage should not matter much...

...is this the place to ask aboot software EQ...???...

...I would imagine one should be suspect of free download, but I don't want to subscribe to some designer program...

...what EQ software would you recommend...???...are any free programs safe...???...

...so far I am liking

RealTime Equalizer 4.10​

 
Last edited:

witwald

Senior Member
Forum Donor
Joined
Jul 23, 2019
Messages
478
Likes
502
...thanks...I just wanted to see if I was the only one who though that...

...I don't hear much above 8k anyway, so the lack of coverage should not matter much...

...is this the place to ask aboot software EQ...???...

...I would imagine one should be suspect of free download, but I don't want to subscribe to some designer program...

...what EQ software would you recommend...???...are any free programs safe...???...

...so far I am liking

RealTime Equalizer 4.10​

Another option for EQ is Equalizer APO, a parametric/graphic equalizer, which can be found here: https://sourceforge.net/projects/equalizerapo/.
 

Hapo

Senior Member
Joined
Jan 11, 2022
Messages
464
Likes
320
...thanks for posting...this is a novel concept for me...I am looking for simple...that program looks like what I had in mind...

...I don't mind paying for a program (once) but freeware is OK too...

...I guess my biggest concern is that the software is safe...I have gotten paranoid aboot downloading stuff, especially "free" stuff...

...another is that I am just not smart enough to use the program...I just wanted an equalizer, not a "project"...

...I am pretty sure I can figger how to use the DBX 1231 or 1215...
 
Last edited:

david moran

Member
Joined
Nov 8, 2017
Messages
41
Likes
69
This is a review and detailed measurements of the dbx 1231 stereo balanced Graphic Equalizer. It is on kind loan from a member and costs US $499.
View attachment 219631

Isn't this an attractive box or what? Makes you want to sit there and just play with all those sliders! Careful though as setting them all back to zero is very time consuming. Fortunately there is a bypass button. Connectivity is extensive in the back:
View attachment 219632
You can even use bare wire if you want!

Note: Harman owns dbx. Our company, Madrona Digital, buys some of their product lines but not these. Still, feel free to read any bias in my subjective remarks.

dbx 1231 Measurements
Let's start with EQ bypassed and input/output of 4 volts:
View attachment 219633

Distortion is at -105 dB which is very good for the class. Don't like the power supply noise but they are at -118 dB so we can ignore them. Turning on the EQ but keeping all the sliders at 0 shows the penalty of the full pipeline:
View attachment 219634

We are right at noise floor of 16 bit audio so not bad still. Here is our signal to noise ratio which is impacted the most:

View attachment 219635

Frequency response is flat in audible band with EQ bypassed:
View attachment 219636

It is hard to get rid of the channel mismatch due to notches in the gain control with the pot itself being fully variable. Repeatability is hard as well for the same reason.

I was pleased to see it handle up to 9 volts input before clipping:
View attachment 219637

IMD distortion is respectable with EQ bypassed and not too bad with it active:
View attachment 219638

Crosstalk is excellent either way: (better than most amplifiers)
View attachment 219639

I was disappointed to see a rise in distortion at low frequencies:
View attachment 219640

Conclusions
Good to see the word "professional" has a meaning here in delivering a low distortion and noise graphic EQ. My memories of consumer units was that they were hiss factories. Not so here. This is a quality piece with reasonable price to match it for analog lovers.

Note that in general, graphic equalizers are poor at dealing with room modes or speaker correction. You need parametric EQ for that. The dbx 1231 has a lot of bands so you may be able to get close with it but still not an optimal tool.

I am going to recommend dbx 1231 graphic eq if you need such a device.

-----------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

>> My memories of consumer units was that they were hiss factories.

This is ignorant unless referring to the dbx 20/20, the company's first automatic equalizer, whose noisefloor was in the -80s and therefore potentially audible in use depending on the usual factors of gain stages, component sensitivities, program, and so on. (There was a pro version, the 610, with the same problem.)

All other dbx consumer (and pro) products were noiseless / hissless in use: The expanders, compressors, stereo spreaders, LF synthesizers, speaker controllers, and the subsequent automatic equalizers were all better than -90 EIN. The same is true of the inexpensive ADC / BSR octave equalizers.

This 1231 pro product, 30y later and more, would be expected to be the same level of quiet or better, and mine certainly is.

To address the posts about EQ 'technique':

It is easy to get good results with such an equalizer, or any other, following common sense. First take temporally (meaning also spatially) averaged pink noise measurements of each speaker from not too far away, say 1-2m, and move the measurement mike within a cubic meter or perhaps a bit less off the tweeter. Use a smartphone RTA app with a continuous (aka forever, aka average) setting. Third-octave. The smartphone mikes are good enough, but a calibrated mike like the iMM6 is inexpensive. Use the equalizer to smooth out the kinks and repeat as necessary or desired.

Check your work at a few listening positions (which will show new kinks) to see if any further adjustment is advisable. Be prudent and use judgment. Repeat with the RTA set to 1/6-octave to see, again, whether anything gross is now revealed (it almost certainly won't be, but all good audio OCD types need to know).

When done, broadly roll off the treble to a medium extent and broadly boost the bass likewise and listen to material you know and see what you think. Adjust further to taste and source deficiency.

Easy-peasy. The averaging is the key, and is not typically possible with the digital "FFT" RC systems, which in the end do not offer (to my ear) the audible success and polish of analog EQ using something like the 1231 and an RTA with pink noise.

This outcome also is achievable, and gets you the most bang for the buck, with octave and half-octave equalizers. Most here would never do such a thing or be satisfied with such, but it makes for instant improvement with lesser systems (desktop, e.g., where there is invariably a haystack centered on 125Hz or so) and "lesser" listeners.

The nice thing about EQ, if you can set aside audiophile prejudices against it, is that it serves as what is drolly labeled an existence proof. The sound and the listening enjoyment are immediately improved! If you can stay openminded, it takes a ton of fretting over phantom hiss, distortion, phase problems, and all of the other alleged analog / nondigital veiling to defeat the clear increase in euphony.

(PS --- if you can latch onto a dbx RTA1 pro unit, it makes all of this gratifying work fast and trivially easy.)
 
Last edited:
Top Bottom