ErinsAudioCorner

[hardisj]

Scanspeak 10F/8414G10 Discovery 4 inch Fullrange

Cliff's: Really good fullrange driver. Nice on/off-axis response linearity with the apparent breakup pushed out to ~16khz. A mild rise in output on the top end (to help combat the otherwise falling response off-axis) that could be easily flattened via DSP with a shelf filter if one were so inclined. Great usability above 300-500hz for higher output (to help overcome the mid-80's sensitivity). Truly an impressive driver for only $73/each (as of this writing).

If needing to use this as a midrange, though, I'd still recommend the actual 4-ohm midrange version of this driver if for no other reason than to gain back the sensitivity this one loses thanks to its fullrange purpose.

https://www.erinsaudiocorner.com/driveunits/scanspeak_discovery_10f8414g10_fullrange/

 

[hardisj]

This is a car audio marketed driver but has the chops to best the majority of 4" mids I've used/tested in the past.

Cliffs: Very low distortion. Nice usable range from 200/300hz to 3khz (low end depending on output; 200hz shouldn't be an issue for most, though but 300hz is easily doable for really high output-minded folks).

Link here:
https://www.erinsaudiocorner.com/driveunits/audiofrog_gb40/

 

[hardisj]

Satori 5-inch Mid/woofer.

Extremely good performance. Would make a very nice option for a midwoofer in a bookshelf or an incredible midrange in a high-output system (speaking from experience here).

https://www.erinsaudiocorner.com/driveunits/sb_acoustics_satori_mw13p-4/

 

[hardisj]

I recently updated my site to include the Time Delay calculator previously on tracerite.com and added both Temperature and Humidity inputs so you can get time delay values with ambient conditions. This is more for the car audio folks who sit off-center but I know some of you exist in this forum so I thought you might also be interested.

In order to kick that off I made a short(ish) video on Time Alignment, what it is and how to use it along with how to use my site. Most of you will already know what you're doing but I wanted it to be a way for newcomers to get an idea of what it is. Hope you all find the video and/or updated site useful. And another thank you to Robert McIntosh for his help with the calculator.

https://www.erinsaudiocorner.com/timedelaycalc/

https://youtu.be/Ys7oylGGcgk

 

[vavan]

Satori 5-inch Mid/woofer

do you happen to have measurements of those sb drivers revel used in f208s?

 

[hardisj]

do you happen to have measurements of those sb drivers revel used in f208s?

Actually, I do. But unfortunately I don't have the FR/HD data. I just have the Klippel LSI data (which tells you the T/S parameters). The measured linear excursion was quite a bit lower than I expected. I'll try to remember to post that up soon.

 

[hardisj]

I made a separate thread because I didn't want to bog this "update" thread down but...

I got a quote back from Klippel and am sending payment soon. I'm asking for donations to help offset my costs. If you want to help out, please see this thread. If not, just ignore and wait for the next round of testing and I'll post it here.

https://www.audiosciencereview.com/...-review-website-using-klippel-products.11761/

 

[kach22i]

In the meantime I have created a new website at ErinsAudioCorner.com.

I have to admit that I'm not a big numbers/chart guy and have been trying to self-teach myself for decades on the topic.

I found your comment on a ring tweeter with a peak perhaps caused by a resonant cavity somewhere very enlightening, it truly cracked some daylight into my brain.

Likewise the review on the 12 inch subwoofer (F12G) with variable phase settings, the interactions with room and main speakers - so much better and simplified explanation for people like me, and yet so comprehensive - thank you.

I would be interested in your perspective on some of the latest M/L products, but see it's been covered elsewhere. I suspect your analysis would be even better though.

MartinLogan Expression 13A Electrostatic Speaker Review with ARC

HiFi News - PDF on same loudspeaker

EDIT:
Splendid is the review of the Tectonic Elements BMR driver, something I've looked at before and wondered about.

 

[hardisj]

I really appreciate the kind words and feedback.

I don't have the time at the moment to read those reviews but just going through the graphs, they do look like interesting speakers. And you can tell Dirac Live is once again performing some magical feats.

 

[AnalogSteph]

I enjoyed going through your driver measurements, despite the unfortunate inconsistencies. The comparison of KEF Q100 and LS50 drivers proved insightful - you can see why one is in their flagship model upon closer inspection of the Klippel graphs: The LS50 driver's Bl(X) curve is about twice as wide for the same deviation from linearity, and L(X) varies by less than 15% instead of almost a factor of 2. In sum this results in distortion being about 10 dB less.

Curiously enough, the LS50 tweeter seemed to have generally lower distortion at 96 dB compared to 90 dB levels where not excursion-limited. Any ideas where this peculiar trait might be coming from? Almost has to be some sort of cancellation (as also typically seen in the frequency range where excursion-related distortion drops to the levels of other mechanisms). Other than that, very typical kind of "tweeter in waveguide" response, a bit rough on axis but very well-behaved off axis with substantial gain towards the lower end.

As an idea for future measurements, there isn't a great deal of data on current-driven performance. I know it's probably not a panacea, but may be worth investigating as tweeters in particular often find themselves after substantial dropper resistors in passive crossovers. A 100 wpc amp with a big ca. 47 ohm (30 W or so) dropper should at least make it to 4 Vrms / 8 ohms (or ~2 W) and would still qualify as a decent enough current source. Bodging together a handful of power resistors seems like a pretty cheap way of getting this kind of measurement.

Now as for the website:
No offense, but there is nothing that spells amateur hour quite as much as underlined headings. It was considered a typographic no-no even back in 2003 or so when I started getting into CSS. Try something like this, perhaps:

h1,
h2,
h3,
h4,
h5,
h6 {
font-weight:bold;
font-family:Arial, Helvetica,sans-serif;
/*text-decoration:underline;*/
text-align:center;
line-height: 1.4em;
color:#fff;
}
h1,
h2 {
  background-color: #596069;
  padding: .5em;
  border-bottom: .2rem solid black;
}

I also noticed the use of non-consecutive Hx tags. The trusty W3C Validator has a handy "outline" option to check for that. It also throws up a few other errors.

As I actually have a page that uses all 6 levels (and yes, I've probably forgotten a great deal of what's on there, most of this was written in 2011-ish), I've had a few opportunities to think about their styling over the years. Actually this got me tinkering again and kept me busy for a day, delaying this post accordingly. There are worse things to do on your vacation.

BTW, I had a look at the website generator you're using (Hugo). Jeez, that's like a whole new foreign language, or going from passive fullrange to active DSP monitor. (Basically, my website still is a late-'90s homepage, just in a fancier dress.) I see that appeal of a static website generator, but I think I stand a better chance of understanding the intricacies of ArgyllCMS in this lifetime than that. Not a big surprise with it being built on something for managing code and programming workflow. Seems like a long way from my little JS calculators that I've been so proud of lately... (I actually wrote my first JS auxiliary function that takes arguments today. Not a new concept to me per se, just something I had never done in this language. Hey, I'm an analog guy, what do you expect?)

 

[hardisj]

I enjoyed going through your driver measurements, despite the unfortunate inconsistencies.

Yea, I just let the software automatically format the axes back then. It bothers me now, too. In future tests I'll be more vigilant about how the data scales are presented.

No offense, but there is nothing that spells amateur hour quite as much as underlined headings. It was considered a typographic no-no even back in 2003 or so when I started getting into CSS.

I kid, I kid.

That said... 1) I am an amateur. 2) I prefer the underline as a clean break. My friend who is a professional said he didn't like it because he wants to click on it. I purposely changed the theme so that all headers would be underlined. It was a conscious choice. Likewise, I looked at your site and it wasn't my cup of tea. Differing opinions here.

BTW, I had a look at the website generator you're using (Hugo). Jeez, that's like a whole new foreign language, or going from passive fullrange to active DSP monitor. (Basically, my website still is a late-'90s homepage, just in a fancier dress.) I see that appeal of a static website generator, but I think I stand a better chance of understanding the intricacies of ArgyllCMS in this lifetime than that. Not a big surprise with it being built on something for managing code and programming workflow. Seems like a long way from my little JS calculators that I've been so proud of lately... (I actually wrote my first JS auxiliary function that takes arguments today. Not a new concept to me per se, just something I had never done in this language. Hey, I'm an analog guy, what do you expect?)

This is my first foray in to coding a website from scratch. And before that, my only coding experience was with Matlab which I learned for my job about 2.5 years ago. My last site was built with WordPress which was akin to using PowerPoint... just easy. Just few days before starting this thread a month ago, I literally didn't even know what Markdown, Hugo, or CSS were. And I sure didn't know how to code in any languages. Suffice it to say, it was like drinking from a fire hose. But now that I've gotten used to it I do like it. I still have trouble with "basic" things that I'll spin wheels on for too long before the lightbulb turns on. But I'm getting there. So I'm proud of the fact that I took on the challenge and am making progress... as slowly as it may be.

 

[hardisj]

My Earthworks M23 mic arrived this morning. I've owned many mics over the years but the build quality of this one is definitely superior. I decided to go with this due to it's superbly flat organic response (even without mic cal file) compared to other electet mics as well as its wide operating range of temperature and humidity.

Thanks to all who helped donate a little bit to the cause. Without you I wouldn't have been able to purchase the mic.


https://earthworksaudio.com/products/microphones/measurement-series/m23/

 

[DonH56]

Congrats! I have been using an M30 for many, many years and I think @amirm has an M40 (probably just to one-up the rest of us).

 

[hardisj]

Congrats! I have been using an M30 for many, many years and I think @amirm has an M40 (probably just to one-up the rest of us).

Thanks! I came thiiiiiis close to buying the M50 or M30 but since the only real difference is how high the response extends, for my measurement purposes it didn’t seem to be any added value to measure past 23kHz.

 

[hardisj]

Klippel unboxing video is up!

 

[hardisj]

This post is for you car audio fans. If you're in to home audio you probably won't find this useful but you might also find similarities between home and car audio as it relates to distributed subwoofers, but with a twist for car audio.



In this video I discuss why I recommend using your subwoofer to improve midbass response. Get your pitchforks ready!... I’m suggesting to run your sub higher than 30hz!

This isn’t truly a shocking revelation. Plenty of people already do what I suggest. It just goes against intuition and against some beliefs in the car audio community that a subwoofer should not play too high in frequency because it can cause the bass to be localized behind you.

The reason why is due to one MAJOR issue in car audio: the “Nearside Null”. This is the large dip in response of the driver’s side midbass speaker that occurs typically in the 70-90hz region. This doesn't occur in every car; there are certainly exceptions to the more extreme car installs.


It is an acoustical null caused by the relationship of the listener’s location relative to the midbass location and generally caused by the width of the vehicle. If you play a track with bass guitar it’s very prevalent; you get a localization to the nearside midbass speaker when the midbass speaker is crossed lower than the frequency where the null occurs.

Generally speaking, the lower your crossover point between midbass and subwoofer, the more noticeable this occurrence is. Unfortunately, this isn’t something you can simply “EQ out”, either. Throwing +6dB at this null may only result in 1dB of actual gain; that means you’re wasting a LOT of power and risking damage to your speaker for no acoustical gain. Some of you may even think to yourselves “seems like you’re not getting much by crossing the midbass low. Maybe there’s not as much benefit as I thought in doing that”. That’s a logical assumption and a lot of times that’s actually true. Crossing the midbass too low can actually result in more “bass behind you”! And you can also take some of the strain off your midbass by crossing them at or above the null. Ironically, we in car audio tend to cross midbass low to get the “up front” bass we so much desire. BUT, IN FACT, the majority of the time you have bass that pulls to the rear is BECAUSE of the midbass nulls. I know that sounds counteractive. But it’s the truth. Standing waves are problematic and this is one symptom of them; whether in home or car audio.

Contrary to popular belief, raising the subwoofer crossover in to the region that this null occurs can actually HELP the sound to stay focused and achieve “up front” bass. If you can move your subwoofer to a location where it is null-free through a frequency above the Nearside Null then you can likely improve midbass without negatively impacting the “up front bass” effect that so many are after. And you can also take some of the strain off your midbass by crossing them at or above the null frequency. Not all have the luxury of space to move the subwoofer around much but experimentation is key here; you may be surprised at the difference subwoofer placement in the trunk can make.

And one important conclusion here is that placing the rear mounted subwoofer on the opposite side of the listening position often results in better response!

 

[hardisj]

Just an update...

I purchased a mic stand over a month ago. After 2 shipping issues, I finally got the 3rd one and it was good to go. I also ordered some speaker stands and planned to use one for speaker testing. But after doing some testing I realized that was a no go. The stand was a bit shaky at above 6 feet. Plus, I wanted something a bit easier for takedown and set up. So I cannibalized my basketball goal (I need a new one anyway

). I buried the pole about 2 feet in the ground and rigged up a platform from HDPE and Plywood (to be sealed soon). The platform can also be swapped out to accommodate larger speakers (floorstanders laid on their side to capture vertical response). The pole is very sturdy and can be removed from the ground and placed in my storage area between tests.

The speaker stand is now at 8.5 feet off the ground and 9 feet away from the patio cover. Nearly everything I test will be reflection free to 9 feet. Which puts the first reflection at about 12 ms; or about 80hz. Doubling that means good resolution above 160hz. That’s good. Real good. More than adequate when you consider I will be using a ground-plane measurement for LF response and "stitch" that to the FF measurement. As for external noise; I live in out in the country. So it's mostly quiet. The software/hardware is smart enough to ignore most noises and multiple sweeps will help keep them from sneaking in to my measurements. IOW, I don't have any concerns here.

I tested hoisting up a 50# bag of sand. That wasn't easy. But was do-able. I'm gonna need a crane, though, if I ever test a floorstander that has significant weight to it. But I'll burn that bridge when I get there.

Here's a few pictures with my 6 foot ladder and myself as a reference.

The last picture is of the mic stand. This sucker is a beast. Can be stood to almost 8 feet tall and the mic can reach higher when the boom is angled.
Here's a link if anyone is wanting to see more info.

 

[StevenEleven]

Cool setup. You are insane (that's a compliment, I've not much patience for sanity). I'm a little worried about the unique slotted front bottom bass port there. Would it be beneficial to move the speaker forward so that the bass port is flush with the front of the platform?

 

[hardisj]

Cool setup. You are insane (that's a compliment, I've not much patience for sanity). I'm a little worried about the front bottom bass port there. Would it be beneficial to move the speaker forward so that the bass port is flush with the front of the platform?

thanks. I think.

That picture was just me saying "yay, I made this!". Any speakers I test would be flush with the platform so there wouldn't be any reflection from it. That goes for the side as well. But, really, the bass portion of the response would be capture by ground-plane measurement. I will likely be stitching that with this elevated measurement somewhere above 200hz and gating it appropriately ... if I had to guess I'd say maybe 300hz just to increase the accuracy of the resolution in high frequencies. Won't know until I start doing some actual testing, though, and see what makes more sense. I'm just happy that the placement allows me the 'headroom' to get reflection free response below 100hz, thus making the resolution above 200hz really useful.

 

[BYRTT]

Hi Erin i could be wrong but in you have kind of anechoic reference curve for one of yours DBR62 couldn't that data be interesting used as calibration for a spicific frozen area in your lab, what i mean is @48kHz measure that speaker on tweeter axis say at 1-2 meters distance and save response as txt-file, now edit that txt-file in a delete of all data below 20Hz and above 20kz, divide txt-file with Amir's on axis to find a difference txt-file, now turn speaker to say hor -20deg step and remeasure plus edit txt-file in all data below 20Hz and above 20kz is deleted and extract the difference txt-file, if the curve of that calculation happen to be equal to Amir's hor -20deg directivity curve will then imagine we have calibrated for your room and gear enviroment and can get anechoic data as long as enviroment and microphone position is never changed.

Could be i'm wrong and waste your time but if you interested i hang on below a zip-folder including induvidual extracted txt-file curves per 10 deg step for Amir's DBR62 analyze.