Affordable Accuracy Monitor Review

[Dennis Murphy]

@Dennis Murphy, please start a new thread on your plans for the Purifi 6.5” once you’re ready. I for one would be very interested! Especially in some kitset form as I live in New Zealand... (shipping...)

I think that would be too self-promotional for the spirit of this site. If I like the results, I'll see whether Amir would be interested in evaluating the design himself. Actually, if I don't like the results and I think the Purifi is to blame, it would still be interesting to see what light Klippel could throw on the subject.

 

[mt196]

Fortunately, PE sells the BR-1 cabinets separately at a very reasonable price, at least before the trade war. So there was no need for me to buy the crossover parts, and I could buy the drivers on my commercial accounted with discount pricing. I've specialized in modding kits and finished speakers because it solves the otherwise insurmountable cabinet problem. I can't build them, having them built to order in the U.S. is too expensive, and meeting the minimum order for Chinese cabinets requires a huge up-front investment and more storage room than I have. For awhile Parts Express had a line of fairly high-quality and reasonably priced cabinets that made it possible for me to start selling the BMR's, but they had so many problems finding reliable Chinese factories that they dropped the line. I had much better luck dealing with Bennic for the Chinese cabinets I used in the most recent BMR's, and they've become much more flexible and eager for business since the tariffs and the virus left their mark. My business partner is currently selling Bennic BMR's in Taiwan, and will soon offer a mini I just designed. Hopefully I'll be able to get the BMR's back into the domestic market in the not-too-distant future.

Ah ok got it. I was interested in replicating what you did in a diy project, can I ask you where can I find data about the internal of the pioneer cabinets? I can easily find outside shape and measures to replicate it, but I don't know how to do the internals. In addition, is this the right woofer used in your mod? https://www.parts-express.com/4-treated-paper-cone-woofer-16-ohm--299-320

Thanks a lot and congratulations for your work!

 

[McFly]

I think that would be too self-promotional for the spirit of this site. If I like the results, I'll see whether Amir would be interested in evaluating the design himself. Actually, if I don't like the results and I think the Purifi is to blame, it would still be interesting to see what light Klippel could throw on the subject.

I would love to know why you don’t like the purifi, if you don’t happen to like the purifi. So far it’s the best mid bass I’ve ever heard. Please post your findings in the threads here and at diyaudio. A little boy waits.

 

[TimW]

After Amir's review of the stock BS22's I went out and bought a used pair for $20. I thought the sound was better then most sub $100 speakers, maybe even the best in that price range. But not spectacular, and not as good as LSR305's.

Then I saw the modification guide for these and had to give it a try. Bought an unopened in box pair locally for $60 and got the RadioShack perf board from their website where it's thankfully still available. The most difficult part of the modification is disassembling the original crossover. Desoldering isn't very fun and the adhesive they use is stubborn!

When I heard the result of the modifications in comparison to my stock BS22's I was quite impressed. The modified version was very clearly better. But with the original having such a high preference rating I worried I could just be imagining things. Or maybe I like objectively bad sound? Very surprised and thankful to see these measured here and showing such excellent performance. Thank you @Dennis Murphy for giving us this great modification.

 

[tsanguine]

I'm most excited to hear that I might be able to purchase a BMR or even a newer version. I had been saving up for a long time when I found out Dennis had stopped selling them. I'm glad you have possibly found a way to balance the stress and hopefully let someone else deal with with the business side.

For anyone interested here is the flatpack for the cabinet and all the electronics if you want to start building one now.

https://meniscusaudio.com/product/phiharmonic-audio-bmr-speaker-kit/
https://www.speakerhardware.com/philharmonic-bmr-flat-pack.php

 

[LDKTA]

Very impressive!

 

[tomtoo]

I am still learning here but have always wondered with these cheaper speakers - if the crossover is always such a compromise why not go active with something like a minidsp and some cheap class D amps? Would that not be a better way to solve crossover errors than with passive components and crossover redesign?
I get here that the tweeter replacement also made a huge difference.

We talk about cheap speakers. Adding DSP and multible amps is not that cheap. A better passive crossover is still far cheaper. And dsp'ing and biamping couldnt also do wonders with the drivers.

 

[MZKM]

my spec was closer to reality than those of a certain speaker company located in Indiana.

Yeah, they I assume are doing some type of in-room parameter instead of anechoic, but not only don’t they state this, it’s like a 6dB boost which is unrealistic.

 

[xarkkon]

Fortunately, PE sells the BR-1 cabinets separately at a very reasonable price, at least before the trade war. So there was no need for me to buy the crossover parts, and I could buy the drivers on my commercial accounted with discount pricing. I've specialized in modding kits and finished speakers because it solves the otherwise insurmountable cabinet problem. I can't build them, having them built to order in the U.S. is too expensive, and meeting the minimum order for Chinese cabinets requires a huge up-front investment and more storage room than I have. For awhile Parts Express had a line of fairly high-quality and reasonably priced cabinets that made it possible for me to start selling the BMR's, but they had so many problems finding reliable Chinese factories that they dropped the line. I had much better luck dealing with Bennic for the Chinese cabinets I used in the most recent BMR's, and they've become much more flexible and eager for business since the tariffs and the virus left their mark. My business partner is currently selling Bennic BMR's in Taiwan, and will soon offer a mini I just designed. Hopefully I'll be able to get the BMR's back into the domestic market in the not-too-distant future.

Hi Dennis, I'm interested in those Bennic BMR's in Taiwan. I'm in Asia, though not in Taiwan, and shipping from Meniscus is an arm and a leg. Any chance I can purchase a kit from your business partner? How should I be going out to reach out to them? Tried searching online but can't find them... Thanks!

 

[headshake]

This speaker has been on my shortlist for my 1st project. The tweeter + bmr is what i am interested in. I might walk my own path though- i am dumb like that.

For anyone interested here is the flatpack for the cabinet and all the electronics if you want to start building one now.

https://meniscusaudio.com/product/phiharmonic-audio-bmr-speaker-kit/
https://www.speakerhardware.com/philharmonic-bmr-flat-pack.php

Dennis has said on another forum that the Phil 3s are not and won't be available as a kit, because the cabinet is just too complex to build (it being a transmission line design, the inside of the woofer's cabinet is quite complex).

https://www.speakerhardware.com/philharmonic-bmr-flat-pack.php

 

[Karu]

Amir just doubled the DIY speaker market with this review

 

[JohnBooty]

I've said this before, but I had the honor of saying hello and briefly chatting with Dennis in a hallway at a show last year and not only is he talented, he is an exceedingly nice gentleman! Truly one of the good guys!

Question for Amir and Dennis: do you reckon one could get a good chunk of the way by applying EQ to the stock Pioneer speaker instead of making physical mods to the driver, crossover and cabinet?

I'm sure they are not on the level of the AAMs via EQ alone, but I can anecdotally confirm these Pioneers are really quite good when corrected with Audyssey EQ and crossed over to a sub. Results will vary based on room of course. They are brightened up a smidge, and to my ears the 70hz hump is gone. I've got more "hi-fi" gear in my office and den, but I just can't justify kicking the Pioneers out of the living room. Like an old car that runs so well you just can't justify replacing it. But as Dennis himself said, the stock tweeter is not wonderful... EQ can only take you so far.

Alternately (and maybe this is what you're thinking of already) anybody who's interested can check out NoAudiophile's DSP corrections for the BS22. I haven't tried his corrections for the BS22 since I'm running them with Audyssey, but I've run his corrections for other speakers and they darn near turn garbage into gold.

I am still learning here but have always wondered with these cheaper speakers - if the crossover is always such a compromise why not go active with something like a minidsp and some cheap class D amps? Would that not be a better way to solve crossover errors than with passive components and crossover redesign?
I get here that the tweeter replacement also made a huge difference.

For you and I, yeah, that would yield better results. For a talented and experienced designer like Mr. Murphy, no.

Broadly speaking, active speakers with built in amplification and DSP for EQ and active crossover duty are the future. Actually it might be more accurate to say it's the present. Bluetooth speakers, soundbars, tablets, phones, laptops, TV speakers, a lot of car audio... outside of the hifi market this is how things are done now. Even within the Hifi market a lot of offerings take the active approach now. Most (all?) studio monitors as well.

So why modify physically modify the xover on these BS22s instead of going fully active? Well, nothing wrong with that route, but you'd still have to perform physical surgery on the Pioneers to disconnect the existing xover network and install a second set of speaker wire terminals, and you'd have a bit of a Frankenstein-looking setup with four channels of amplification, a MiniDSP in the middle of the signal chain, and a whole bunch of extra cabling. Plus extra wall warts. You could cram all of that inside one of the speaker cabinets but that brings its own hassles and compromises.

Also....

I've had a lot of fun (and continue to have a lot of fun) with DSP-based setups.

But man do I also love the simplicity of an analog, two-channel setup.

I'm a software engineer by day and sometimes I really value simplicity in my leisure time toys after doing battle with technology for 8+ hours a day.

 

[QMuse]

Alternately (and maybe this is what you're thinking of already) anybody who's interested can check out NoAudiophile's DSP corrections for the BS22. I haven't tried his corrections for the BS22 since I'm running them with Audyssey, but I've run his corrections for other speakers and they darn near turn garbage into gold.

Why would you want to try his correction when he didn't make measurement after it to check how it really went?

Btw, those correction parameters are looking very odd to me:

- I have no idea why he used filter at 92Hz
- filter at 560Hz is too narrow and gain is too small
- those 2 filters at 13800 and 15800 are overkill resulting from using Auto EQ feature. One filter would suffice. You want to keep number of filters as small as possibe in this range.

 

[DDF]

What a great post. I'm not sure I deserve all of that imputed wisdom, but you certainly know your stuff. Just one comment--i didn't really start out to increase the output from 800 Hz to 3kHz. I actually brought it down compared with the stock 22. What you're not seeing on the Klippel measurements is the impact of the room on the response below 800 Hz or a little lower. Actually, it's getting late and I'll add to this post tomorrow to explain what I'm after here. But in the meantime, thanks for clarifying the crossover point. I targeted 2600 Hz, and I came out pretty close. Although the crossover slopes are 18 dB electrical, as I'm sure you know, the more important acoustic slopes are 24 dB.

Thanks allot Dennis. I'm looking forward to see what you do with the Purifi. I like the 8545 (and use it), but the Purifi looks like a big step up.

 

[Sonny1]

This has been one of my favorite threads on ASR. Very good questions from the group, great news on Dennis’ future plans, incentive for me to update the Pioneers with the parts I have gathering dust for the last couple years, etc. I’m most excited to hear Phiharmonic will be rising from the ashes! Glad Dennis is planning to adjust the way he manages the company to leverage his skills without having to give up all of his personal time. He is supposedly retired after all!

I had been considering the BMR’s for a while and it looks like an improved version is on the horizon. Exciting stuff!

 

[Matthew J Poes]

Naaaaaaa. Distortion wasn't the problem with the stock tweeter, at least not at the moderate playback levels favored by true gentlemen. The murky quality that infected the stock BS-22 was coloration from the little wave guide and was apparent at virtually any playback level. If you ever get a chance to listen to the Monoprice tower mod I did for Audioholics James, it sounds fine at reasonable SPL's, and the little AMT tweet clocks in with 12% THD at 86 dB. Also, all of the RAAL ribbons display THD levels very close to the Pioneer tweeter, and at lower frequencies (around 2 kHz) where the first harmonic(4 kHz) should be more audible than the 9 kHz - 11 kHz range of the 22's first distortion component. You're not allowed to reply to this post because that would be off topic and might raise factual issues that could undermine my reasoning.

Ok fine I won't reply!

 

[JeffS7444]

Close enough for retired government work. They sold for $165/pair and shipping usually brought that up to $185 - $190.

Hi Dennis, is there any one place on the web where you're keeping all your DIY notes? Info on murphyblaster.com seems very incomplete. Someone did post a good illustrated guide to the SP-BS22-LRs
https://audiokarma.org/forums/index...-pioneer-sp-bs22-lr-diy-modifications.610820/
But that seems more the exception, and elsewhere, you've dropped tantalizing tidbits such as this one about an inexpensive Sony speaker:
https://www.audiosciencereview.com/...3-way-speaker-review.13562/page-7#post-410095
And unlike the Pioneer SP-BS-22-LR, Radio Shack Minimus 7 and Linaeum speakers, the Sony has the big advantage of currently (May 2020) being in stock at Best Buy.

 

[HooStat]

So why modify physically modify the xover on these BS22s instead of going fully active? Well, nothing wrong with that route, but you'd still have to perform physical surgery on the Pioneers to disconnect the existing xover network and install a second set of speaker wire terminals, and you'd have a bit of a Frankenstein-looking setup with four channels of amplification, a MiniDSP in the middle of the signal chain, and a whole bunch of extra cabling. Plus extra wall warts.

I was thinking of trying to do this to get a better understanding of DSP and crossovers. Has anybody done this?

 

[ribosradagast]

Dang, now knowing that there's a "BMR 2" on the way puts my plans on making the flat-pack BMR 1 on hold!

Someone needs to get theirs to Amir for testing. The hype is real.

 

[JohnBooty]

I was thinking of trying to do this to get a better understanding of DSP and crossovers. Has anybody done this?

You mean modifying an existing passive commercial speaker to use an active crossover? Or building a speaker project from scratch with an active crossover? In both cases, the answer is "yes" -- it's pretty common. I don't have a particular shining example in mind but there are a lot out there. PartExpress's Tech Talk forum has lots of DIY project talk.