Tone control

[Multicore]

There were plenty of otherwise identical amplifiers sold to the public in the 80s and 90s where the tone circuitry was simply not populated on the PCB and a few links bypassed it. Rapturous reviews of course. The first run of Pioneer's A-400 was a stripped down A-44x model. I remember removing the cover, only to see a ton of unpopulated PCB and a bunch of links. LOL. And it cost more. We sold tons of them to stupid audiophools.

I remember the popularity of A-400. I was in Germany at the time where the equivalent model had controls. I guess German magazines hadn't gone down that road.

 

[Multicore]

I do not like computer sliders and latency and having to program for something I don't use all the time ... turning a knob with real time response is my preference, for me it is the right tool for the job.

Knobs are good. The trick is getting the right knobs with the right circuitry under your fingers.

 

[kongwee]

the amps I'm looking at are Marantz PM8006, Cambridge Audio CXA81 & Acram SA20, don't want a class D amp & don't really know about class G the Acram uses.

I am pretty some shop will have all these three model if you can make the effort to audit it.

 

[Hiten]

Wel, if you want to go technical, you can check the service manual, and see they use the very generic BD3491FS IC for input switchting, eq and volume. That is an analog IC. that has a kind of varistors build in that can be controlled by other ic's (analog or digital). The buttons steer the digital chip (in the service manual called the RS100JEAFA, but unknown to me), that also manage the display and the rotary. That is called digital controlled analog with IC's. That can also be done discrete, but it's much harder and expensive to do it right that way so most do it with IC's (and when done right it's not an issue).

ok. Got that.
I did searched for service manual. I dont have much knowledge but I often browse these things out of curiosity and to learn. (Currently halfway through building lm1875 amp with bypassable ready tone control module just for fun)
thanks and regards.

 

[LouB]

I am pretty some shop will have all these three model if you can make the effort to audit it.

No tone control on the Cambridge or Acram so there off the list.
Thanks

 

[Trell]

The RME ADI-2 DAC has it all, of course: you can adjust the frequency range of the tone control, and how much it does. The same is true for the dynamic loudness function, not to mention the filters. Only a fully adjustable digital graphic equalizer will do more.

And the tone controls are easy and convenient to use with two knobs on the ADI-2 DAC, or using the remote control. No way I'm going to fiddle with a PEQ or three for a change that is temporary and based upon content just playing.

 

[MarkS]

Although the OP isn't interested, I am going to again plug the Lyngdorf system, which has digital tone controls with adjustable hinge frequencies on its web interface, with no response lag.

I find that adjusting the hinge frequency in the bass is extremely useful for fine-tuning the sound on particular tracks, and that being able to this while in my listening seat is a huge advantage.

 

[LouB]

Although the OP isn't interested, I am going to again plug the Lyngdorf system, which has digital tone controls with adjustable hinge frequencies on its web interface, with no response lag.

I find that adjusting the hinge frequency in the bass is extremely useful for fine-tuning the sound on particular tracks, and that being able to this while in my listening seat is a huge advantage.

View attachment 255372

I am interested ! I've just sold myself on non-digital AB amp for reasons I can't really pinpoint. What I think is great on the Lyngdorf is the built in room correction & from what I've read it really works well. Seems to make so much more sense (for a guy like me, a simpleton) & user friendly having that bulit in is huge plus. When it comes time to upgrade the AV amp I'll defiantly have a look at the Lyngdorf line, but I better start saving now !

 

[MarkS]

The TDAI-1120 lists at $2450, and there is an open-box one for $2000 on ebay right now from the dealer I bought mine from (by mail order):

LYNGDORF TDAI-1120 RoomPerfect Integrated Amp /DAC AUTHORIZED-DEALER $2450 List | eBay

Find many great new & used options and get the best deals for LYNGDORF TDAI-1120 RoomPerfect Integrated Amp /DAC AUTHORIZED-DEALER $2450 List at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[ai1]

I am not sure if my question fits this thread (the name looks OK), but I have a different but somewhat similar need:
I am looking for a tone control for my stereo installation which consists of minidsp 4x10hd used for input selection, volume control and active filtering, and multi-channel power amplifier which drives the speakers. I would like to have several frequency-response presents - tilded, v-shaped, etc., and also equal loudness compensation. What would be my choice?

Before continuing, here is the answer by chat GPT https://chat.openai.com/chat when asked this exactly question

It sounds like you are looking for a tone control unit with a variety of frequency response options and Fletcher-Munson loudness compensation. One option you might consider is a digital signal processor (DSP) with the ability to perform active filtering and volume control. Many DSPs offer a variety of frequency response options and also have the ability to implement Fletcher-Munson loudness compensation. The MiniDSP 4x10HD that you mentioned is a good example of a DSP that could be used for this purpose.
There are many other DSPs on the market that might also be suitable for your audio installation, so you may want to do some research and compare different models to find one that meets your specific needs. Some factors to consider when choosing a DSP include the number of channels, the range of processing options available, the user interface, and the cost.
...

I understand that the above Lyngdorf unit would fit, yet I would prefer a less expensive solution if available.
I mostly use digital sources, but also analog from time to time (like twice per year, when our daughter is visiting), I would prefer a digital output to feed 4x10HD.
Initially, I was thinking of Behringer DEQ2496 or something from the minidsp family. Unfortunately, DEQ2496 lacks remote control, which is nogo for me. I do not know if loudness compensation may be implemented using minidsp. Furthermore, switching presets of minidsp (my experience is with 4x10HD) produces some quite unpleasant noises; I am wondering if Flex also exhibits the same behavior.
I do not know exactly what the DSP of RME-ADI 2 is capable of, but if it can do the tone controls I am looking for (and is the cheapest option), I will probably survive the absence of the analog input and digital outputs.

 

[LTig]

I do not know exactly what the DSP of RME-ADI 2 is capable of, but if it can do the tone controls I am looking for (and is the cheapest option), I will probably survive the absence of the analog input and digital outputs.

The RME ADI2 DAC can do all you desire, and if you need an analog input the similar capable RME ADI2 PRO has one, but at a price.

 

[Peterinvan]

I assume analogue EQ doesn't drop any bits?

Schiit Audio: Loki Mini + ​

"Loki Mini+ uses a single, discrete, current-feedback gain stage, coupled to passive LC filters for 3 bands, plus a gyrator for the bass" ????

 

[levimax]

I assume analogue EQ doesn't drop any bits?

Schiit Audio: Loki Mini + ​

"Loki Mini+ uses a single, discrete, current-feedback gain stage, coupled to passive LC filters for 3 bands, plus a gyrator for the bass" ????

No dropped bits but a little noise and distortion although the specs on this look good. A good 32 bit digital solution or a good analog solution will both work fine.

 

[coonmanx]

Each of my three systems utilizes a graphic EQ. A lot of folks don't like them but when used reasonably they do well for me. I don't have any smiley faces on them. Just a very small and gentle curve that is not that far off from flat. Slight boost at the bottom and then maybe one or two very small tweaks elsewhere. Two are ten band and one is a seven band. But using them requires a tape loop that some modern amps do not have. To me, they just give me a little bit more adjustment than two tone controls...

YMMV...

 

[jsrtheta]

Each of my three systems utilizes a graphic EQ. A lot of folks don't like them but when used reasonably they do well for me. I don't have any smiley faces on them. Just a very small and gentle curve that is not that far off from flat. Slight boost at the bottom and then maybe one or two very small tweaks elsewhere. Two are ten band and one is a seven band. But using them requires a tape loop that some modern amps do not have. To me, they just give me a little bit more adjustment than two tone controls...

YMMV...

I use a graphic EQ as well. I don't use the tape loop at all, just the regular inputs/outputs. Never saw much point for my purposes in using the tape loop.

 

[LTig]

I use a graphic EQ as well. I don't use the tape loop at all, just the regular inputs/outputs. Never saw much point for my purposes in using the tape loop.

You need the tape loop if your integrated amp has no connectors for preamp out and poweramp in. Or the EQ is so noisy that it needs to run before the volume control.

 

[jsrtheta]

You need the tape loop if your integrated amp has no connectors for preamp out and poweramp in. Or the EQ is so noisy that it needs to run before the volume control.

It's definitely not noisy. And I don't use and integrated amp. So, all good so far.

I first got one based on advice from a friend who did a lot of recording for bands and had his own studio.

I stopped when I got into "high end" gear, and was taught that it was the wrong thing to do, that the signal path had to be as simple as possible. This went on for years, until I decided it was kind of dumb, and went back to using one. And I found the cleanest one I could, and never looked back.

 

[LTig]

It's definitely not noisy. And I don't use and integrated amp. So, all good so far.

I first got one based on advice from a friend who did a lot of recording for bands and had his own studio.

I stopped when I got into "high end" gear, and was taught that it was the wrong thing to do, that the signal path had to be as simple as possible. This went on for years, until I decided it was kind of dumb, and went back to using one. And I found the cleanest one I could, and never looked back.

Same story here, but I bought the Behringer Ultrafex Po when a colleague showed me the non pro model and what it could do. The pro model has two relays which connect imput and output when it's not powered to make sure sound comes through in case of failure (important for pro applications). For me it's perfect because I can leave it in the chain permanently ahd don't need to worry whether it influences the sound when not in use. I use it only to improve bad recordings (stereo widener, low bass enhancer) and if there is a bad influence on sound it's totally swamped by the improvements the prcessing does.

 

[jsrtheta]

Same story here, but I bought the Behringer Ultrafex Po when a colleague showed me the non pro model and what it could do. The pro model has two relays which connect imput and output when it's not powered to make sure sound comes through in case of failure (important for pro applications). For me it's perfect because I can leave it in the chain permanently ahd don't need to worry whether it influences the sound when not in use. I use it only to improve bad recordings (stereo widener, low bass enhancer) and if there is a bad influence on sound it's totally swamped by the improvements the prcessing does.

I'm at the age where high frequencies are becoming an endangered species.

I use an old Coustic EQ, which is extremely clean. But I will look at that Behringer for sure.

 

[LTig]

I'm at the age where high frequencies are becoming an endangered species.

I use an old Coustic EQ, which is extremely clean. But I will look at that Behringer for sure.

This one is long out of production. I'd rather go for the Behringer Ultracurve Pro DEQ2496 (measured here) which can do many many (many) more things.