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Affordable Accuracy Monitor Review

laudio

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Very nice. One of these days I will smooth out my JBL L100s with a Murphy designed crossover.
 

wwenze

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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.

That's why speakers with DSPs are popping up these days. LSR305 is one of the more famous ones.
 

Beave

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I am saddened that I didn’t pull the trigger on any of the Dennis Murphy speakers when he was still making them. I wonder how the BMR and my favorite, Philharmonic 3s measure.

I think the BMR can be bought as a kit. What about the 3’s @Dennis Murphy, are those available as a kit?

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).
 

wwenze

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Dennis improved the response in the frequency domain. How did his crossover mods affect the response in the temporal domain?

Slow decay in waterfall is caused by stored energy in certain resonant frequencies. This includes electrical / magnetic i.e. LC circuit is a resonator. Energy needs to be dissipated e.g. damping resistor.

The drivers also store energy that's why we dissipate them better when impedance seen by driver is low. Probably not the case here but maybe just in case.

EDIT: Nvm, apparently there is extra foam in the cabinet

Schematic and stuff
https://audiokarma.org/forums/index...-pioneer-sp-bs22-lr-diy-modifications.610820/
 
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hyperplanar

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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?
It really is such a compromise, even with non-cheap speakers. But audiophiles are obsessed with component matching and tweaking so that's why basically every home speaker is passive.
 

Stump909

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Hearing about Dennis's retirement hit me hard a couple years back. The Phil 3's were my end-game target.
 
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ROOSKIE

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Hearing about Dennis's retirement hit my hard a couple years back. The Phil 3's were my end-game target.
Yah, I kept waiting to buy the BMR's. Woops, why did I do that?
Anyway, great to see these speakers measured. Quite an improvement and fun now as a project for anyone with a little of the DIY/modder blood.
 

ROOSKIE

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It really is such a compromise, even with non-cheap speakers. But audiophiles are obsessed with component matching and tweaking so that's why basically every home speaker is passive.

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.
You have to think about the complexity. Adding a minidsp and a amp for each drive unit is really a fairly advanced task. Correctly programming the minidsp and even just correctly setting the gains on the amp requires skills and extra gear such as REW software and a microphone. Many people do this and the net is filled with ideas and examples but this is not consumer mentality, it is DIY mentality. There is no better way to become a tweaker than to get something like a home brew system.
If you want to make a consumer product all of that has to be in one box and well integrated and easy to use, you end up with something like the KEF LS50w and that costs cash.
Or if you are smart and don't need the wireless and the app, you go with some solid studio monitors. There are some real decent budget studio monitors out there with true active design.
You also have to remember that many folks (audio nuts included) are not actually buying to get better sound. In our consumer culture buying is a sport and a pastime. Not saying this is good or bad but many folks are not buying new 5K speakers for better sound anymore than they bought a 2k watch for more accurate time, or 50k car to get better at getting to the grocery store. 90% of what many folks buy is simply because we buy stuff here.
 

Bruce Morgen

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Next, one of Danny "Tube Connector" Richie's mods -- he sells parts kits for dozens of popular, relatively low-cost speakers. His affinity for silliness like those connectors and "audiophile" Mills resistors notwithstanding, he seems to know exactly what he's doing when it comes to crossover and enclosure improvements.
 

Promit

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The BS22 was my desktop speaker setup for a year or two, and a quartet of the AJ FS52 plus the center were my first "big" home theater speakers. It took a while to understand what I was hearing but it eventually became clear that I wasn't imagining it and the tweeter was horrible. I not only swore off many of the AJ designs, but also all of the audio reviewers who lavished praise on those speakers. (Overreaction? ¯\_(ツ)_/¯)

I'm absolutely blown away at how much Dennis Murphy was able to transform these speakers. Unreal.
 

ROOSKIE

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Next, one of Danny "Tube Connector" Richie's mods -- he sells parts kits for dozens of popular, relatively low-cost speakers. His affinity for silliness like those connectors and "audiophile" Mills resistors notwithstanding, he seems to know exactly what he's doing when it comes to crossover and enclosure improvements.
I'd love to see a GR research design here. He does come in a mixed bag that is for sure, some artists are just odd (no way on those tube connectors) but seeing the results here would be interesting for sure.
 

hyperplanar

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You have to think about the complexity. Adding a minidsp and a amp for each drive unit is really a fairly advanced task. Correctly programming the minidsp and even just correctly setting the gains on the amp requires skills and extra gear such as REW software and a microphone. Many people do this and the net is filled with ideas and examples but this is not consumer mentality, it is DIY mentality. There is no better way to become a tweaker than to get something like a home brew system.
If you want to make a consumer product all of that has to be in one box and well integrated and easy to use, you end up with something like the KEF LS50w and that costs cash.
Or if you are smart and don't need the wireless and the app, you go with some solid studio monitors. There are some real decent budget studio monitors out there with true active design.
You also have to remember that many folks (audio nuts included) are not actually buying to get better sound. In our consumer culture buying is a sport and a pastime. Not saying this is good or bad but many folks are not buying new 5K speakers for better sound anymore than they bought a 2k watch for more accurate time, or 50k car to get better at getting to the grocery store. 90% of what many folks buy is simply because we buy stuff here.
I totally agree. Didn't mean to suggest people should be building their own speakers/ripping out the existing crossovers in their passive speakers, just that off-the-shelf active home speakers are few and far between. There's plenty of studio monitors, but a lot of people discount them for home use due to their aesthetics.

There should be a large market for <$1000 well designed active speakers with appealing aesthetics.
 

Dennis Murphy

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I am saddened that I didn’t pull the trigger on any of the Dennis Murphy speakers when he was still making them. I wonder how the BMR and my favorite, Philharmonic 3s measure.

I think the BMR can be bought as a kit. What about the 3’s @Dennis Murphy, are those available as a kit?

The 3 is just too complicated for that. Also, if you combine the BMR with a good sub, you're awfully close to the sound of the 3 for a lot less money.
 
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goldark

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The 3 is just to complicated for that. Also, if you combine the BMR with a good sub, you're awfully close to the sound of the 3 for a lot less money.

Dennis, your affordable accuracy speakers have one of the highest preference ratings (used with a subwoofer) on the site so far. I assume you feel your BMR is the superior speaker. Would you expect a similar preference rating? And if so, what, besides bass performance/power handling, would you attribute the upgrade in sound quality to? (Once again assuming a high preference rating for the BMR as well - basically I'm asking if 2 speakers both have similarly high preference ratings, what factors would cause one to sound better than the other?)
 

Dennis Murphy

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Speaking of which...

Is there any plan to review the BRM Philharmonitor?

@amirm, @Dennis Murphy ?


#flattenthecurve

I hope not. They've already been subjected to a full Spinorama test on Audioholics, and I had them measured by NRC. I never published the latter because the NRC tests aren't calibrated correctly to show bass response accurately for many speakers with rear ports. There's a bump in those measurements around 100 Hz that just isn't there. I did show the far off-axis results on my web page, however, because all speakers have a rising bass response in those tests. Since members on this forum are a lot more sophisticated about and interested in measurements, I've included the on-axis through 30 degrees off axis results below. I don't think there's much to be learned from another test. I will soon be working on a Super BMR that uses the Purifi 6.5" woofer that's in high-buzz-mode on the Internet. My pair of those drivers will arrive shortly and if they live up to the hype, I would be happy to send the upscale BMR to Amir. I think people would find those results much more interesting since I don't think any other commercial speakers use them yet.
 

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MZKM

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I hope not. They've already been subjected to a full Spinorama test on Audioholics, and I had them measured by NRC. I never published the latter because the NRC tests aren't calibrated correctly to show bass response accurately for many speakers with rear ports. There's a bump in those measurements around 100 Hz that just isn't there. I did show the far off-axis results on my web page, however, because all speakers have a rising bass response in those tests. Since members on this forum are a lot more sophisticated about and interested in measurements, I've included the on-axis through 30 degrees off axis results below. I don't think there's much to be learned from another test. I will soon be working on a Super BMR that uses the Purifi 6.5" woofer that's in high-buzz-mode on the Internet. My pair will arrive shortly and if they live up to the hype, I would be happy to send the upscale BMR to Amir. I think people would find those results much more interesting.
Is this the original design or the revision when you had to use different cabinets?

As for the Purifi woofer:
https://hificompass.com/en/reviews/purifi-audio-ptt65w04-01a-midwoofer

Really weird looking surround, looks like it got melted in the sun.
Pretty good performance, especially the IMD. It starts to beam ~1.5kHz.
 
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Xyrium

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Me likey this conversation...subbed.

BTW, it appears that Meniscus Audio still sells the BMR kit, for those interested.
 

Dennis Murphy

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Neat. The on-axis variations all but disappear in the listening window too.

Thanks for pointing that out. That curve is a little hard to make out unless you're looking for it. It's really not possible to smooth out all of those little on-axis diffraction wobbles with a passive crossover, and probably not worth doing with an active one. All of my speakers are designed to be listened to with little or no toe-in, so the first arrival sound will be reasonably free of the diffraction effects, and any that remain at various angles will tend to fill in from all of the reflections. This assumes, of course, that we're really dealing with cabinet edge diffraction and not inherent resonances in the drivers themselves.
 

Dennis Murphy

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Dennis is a really talented crossover designer. Not just because he can make expensive speakers that perform well, but because he can do the same cheaply.

I’m also glad Amir measured these. Now I can complaint to Dennis that i was in fact correct that the Pioneers have a distortion issue in the treble. I did comprehensive measurements on these a few years back and noted that the distortion rose dramatically near the crossover point when played back at levels that are modest in a room. He didn’t measure distortion but strongly disagreed with me that there was ant such problem in the original design. Yet clearly his upgrade and replacement of that problematic tweeter dramatically lowered the distortion.

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.
 

Dennis Murphy

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I would be curious about how my updated version of the "Affordable Accuracy" measure. These were based on a widely available Dayton kit from Parts Express. I had an email exchange with Dennis a few months ago, where he informed me that he is no longer making speakers, and that he offered the crossover for the Dayton Affordable Accuracy version to Parts Express and that they turned him down. That is a real shame, since I prefer these to multiple budget speakers that got good reviews here.

The latest affordable accuracy wouldn't measure as well in the upper treble because the Dayton "silky" tweeter has a fairly prominent peak at 15kHz and has less-than-stellar quality control. Parts Ex;press reverse engineered a more expensive Morel tweeter with stricter tolerances, and I offered the real-deal Morel as an upgrade. Either speaker would measure with much greater bass extension and power handling than the BS22 Mod. PE assigned me a new account rep and I'm going to forward this review to him to see if I can get them to change their minds. Maybe it will give me more credibility. The Dayton woofer has amazing bass performance--far better than the woofers used in other budget speakers. It does have to be crossed at around 1900 Hz, which is why I couldn't use the Vifa tweeter I used in the 22 mod.
 
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