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Perlisten S7t Speaker Review and Measurements (Audioholics)

abdo123

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Until the Revel F328Be and the S7T are measured in the same exact manner and listen to side by side it's hard to know which a listener might prefer. The Revel F328Be sounds absolutely great to me. I can't imagine wanting much more. I can easily use them without sub for music listening. Based on the S7T roll off at 80Hz a sub would most likely be required with it.

As far as distortion, Amir's review sums it up nicely for the F328Be.


View attachment 131337

Tbh at this price range you should get a sub because not only the placement of stereo speakers completely bonkers for subbass but intermodulation distortion is nasty in a full range speaker, no matter how low the harmonic distortion of the drivers is.
 

Haint

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The vertical dispersion is definitely unique, curious to see if that results in a very different sound in the comparison. I'd expect that aspect to be much more transformative to the SQ than the distortion.
 

ctrl

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The Revel F328Be ...I can easily use them without sub for music listening. Based on the S7T roll off at 80Hz a sub would most likely be required with it.
How much low bass sound pressure level someone needs to be satisfied is of course individually different, but to portray the two or one of the speakers as if no subwoofer is needed (related to technical properties, not auditory taste) would deny the subwoofers their raison d'être.

A good subwoofer shows f3 of <25Hz. According to Amir's measurements, the F328Be shows an f3 of 63Hz and an f6 of 45Hz. This is light years away from what a good subwoofer has to offer in terms of bass.

There are comparable speakers that really don't need a subwoofer (only related to the low-frequency response of the loudspeaker, not to the flexibility in terms of combating room modes), for which sensitivity is traded for bass.
Here is an example of a 1.7m high speaker with three comparable woofers, but designed as long-throw subwoofer drivers that are crossed over at 160Hz.
1621706078724.png 1621706146419.png 1621707029272.png
The speaker achieves an f3 of 23-25Hz, even according to "independent" tests. For this, the sensitivity is "only" 84-87dB (depending on the reviews).

As long as a loudspeaker does not reach (IMO) at least an f3 of 25-30Hz (depending on the filter slope drop), technically a subwoofer is always necessary - as already mentioned, personal listening taste may perceive this differently.
 
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amper42

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How much low bass sound pressure level someone needs to be satisfied is of course individually different, but to portray the two or one of the speakers as if no subwoofer is needed (related to technical properties, not auditory taste) would deny the subwoofers their raison d'être.

A good subwoofer shows f3 of <25Hz. According to Amir's measurements, the F328Be shows an f3 of 63Hz and an f6 of 45Hz. This is light years away from what a good subwoofer has to offer in terms of bass.

There are comparable speakers that really don't need a subwoofer, for which sensitivity is traded for bass.
Here is an example of a 1.7m high speaker with three comparable woofers, but designed as long-throw subwoofer drivers that are crossed over at 160Hz.
View attachment 131348 View attachment 131349 View attachment 131352
The speaker achieves an f3 of 23-25Hz, even according to "independent" tests. For this, the sensitivity is "only" 84-87dB (depending on the reviews).

As long as a loudspeaker does not reach (IMO) at least an f3 of 25-30Hz (depending on the filter slope drop), technically a subwoofer is always necessary - as already mentioned, personal listening taste may perceive this differently.


The Revel F328Be measures -2dB at 29Hz and -6db at 25Hz without EQ in my room with REW. As you can see below Amir revised the F6 measurement to 29Hz with "Bass numerical optimization". I have dual HSU VTF-3 MK5 HP Subs that I use with the Revel for Home Theater but for simply playing music at modest listening levels I really enjoy the sound of the F328Be in a stereo only configuration (full range) without subs. There is a continuity of sound with this configuration that pleases my ears. Obviously, others may differ.

My setup allows me to add subs with the touch of the remote or go full range without them. It's been fun listening to the different configuration options.


Revel F328Be On-axis response improvement Klippel NFS.png
 

ctrl

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As you can see below Amir revised the F6 measurement to 29Hz with "Bass numerical optimization".
If the graph is correct, then based on 91-92dB sensitivity, f6 is at about 60Hz, the f10 point is about 29Hz. Amir must have made a mistake there - some hair splitting ;)

I really enjoy the sound of the F328Be in a stereo only configuration (full range) without subs.
I believe you, as I said, personal taste can feel completely different.

From a purely "technical" point of view, neither speaker comes close to subwoofers. When using subwoofers, there are (besides advantages) of course all kinds of potential problems - matching filter slopes, high group delay,...
 

MZKM

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If the graph is correct, then based on 91-92dB sensitivity, f6 is at about 60Hz, the f10 point is about 29Hz. Amir must have made a mistake there - some hair splitting ;)
Those are the values I gave him, using the LFX calculation, which compares -6dB Sound Power to Listening Window average (300Hz-10kHz).

SP has a decent bit higher SPL than on-axis in the bass.
Spinorama 51.png
 
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amirm

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One thing to keep in mind as well is how accurate this approach is to capturing the distortion of a speaker. There are a lot of unknowns. I talked with one of Harmans speaker engineers about measuring speaker distortion and what he told me was they always do it in an anechoic chamber with a 1” B&K capsule. It’s a very specific mic with extremely low noise and distortion. The mics own self noise and distortion ideally needs to be at least 10dB better than the DUT. The room should also be. While there are some tricks that let you stretch these margins, his comment to me was he doesn’t trust them.
Klippel recommends (very) near field measurements for distortion as long as speaker distortion is >> mic which is the case with mine. That way you get around noise issues and lower bounds for the mic. I measure at 1/3 meter and report at 1 meter.

There are room modes that exaggerate distortion measurements indoor. Klippel NFS is able to filter these out and I used to do that but stopped a while ago as the room is constant in all of my measurements.

In general, you cannot compare one measurement against another. They should all be used as a relative measure to each other.
 

Matthew J Poes

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Klippel recommends (very) near field measurements for distortion as long as speaker distortion is >> mic which is the case with mine. That way you get around noise issues and lower bounds for the mic. I measure at 1/3 meter and report at 1 meter.

There are room modes that exaggerate distortion measurements indoor. Klippel NFS is able to filter these out and I used to do that but stopped a while ago as the room is constant in all of my measurements.

In general, you cannot compare one measurement against another. They should all be used as a relative measure to each other.

I think we are saying much the same thing here. The nearfield measurement is also what is in the standard. To be honest, while speaker distortion is many orders higher than mic distortion, I don’t know that it is fair to say you know yours is way less than every speaker. I believe Klippel uses GRAS half inch mics right? They have put out data in their mics before using their calibrators, since those have a pure tone and a known distortion that is extremely low. What I recall is that it was potentially close to where some of the new breed of very low distortion drivers are. Maybe too close. I used to have those saved. If I can find the report I will share.

We know the same individual who made this comment. He told me they measured in the chamber with the B&K mic and have compared to the Klippel in the past. That the Klippel numbers were off. So he does all his distortion tests the old fashioned way. If I recall, the conversation was in the context of driver testing. Not speaker testing.

In any case. I agree with you. People shouldn’t compare distortion measurements between testers. I also have very little faith that the Earthworks mic that James uses has low distortion.
 

Matthew J Poes

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If the graph is correct, then based on 91-92dB sensitivity, f6 is at about 60Hz, the f10 point is about 29Hz. Amir must have made a mistake there - some hair splitting ;)


I believe you, as I said, personal taste can feel completely different.

From a purely "technical" point of view, neither speaker comes close to subwoofers. When using subwoofers, there are (besides advantages) of course all kinds of potential problems - matching filter slopes, high group delay,...
Subwoofers don’t inherently add group delay. That’s just a design problem. All speakers have rising group delay at the bottom of their bandwidth. Ported has more usually. But some speakers are designed to monimIe group delay.

brands like SVS have very high group delay because of both their DAP choices and tuning approach. JTR actually has extremely low group delay, especially their sealed.

Perlisten are sealed and have very low group delay. The upcoming ported series will be designed to minimize group delay. While I know many dismiss group delay as unimportant. Dan and I are of the same mind as he actually designs ported boxes much the same way I do. Im excited to see how those turn out.

min my opinion all speakers should be used with subwoofers. It’s always better when done correctly. Subwoofers are inherently better at reproducing bass.
 

Absolute

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Beautiful speakers and most likely supremely good-sounding in rooms where you have a fair distance to side walls. Not particularly impressed by the sudden shift in dispersion width in a critical area of our ears, though. Might not be a big deal, but it could be. The horizontal dispersion is by far the most important factor for me in any speaker.
 

Matthew J Poes

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Beautiful speakers and most likely supremely good-sounding in rooms where you have a fair distance to side walls. Not particularly impressed by the sudden shift in dispersion width in a critical area of our ears, though. Might not be a big deal, but it could be. The horizontal dispersion is by far the most important factor for me in any speaker.

I’ve talked to Dan about this as well.

its not as bad as you make it out to be. it’s certainly better than most speakers. Most show a dispersion shift. Often more than one.

in this case, Dan pointed out that the timbre of the speaker is primarily going to be set by the listening window. The listening window and early reflections windows both look very good. I hope to share the data differently at a future date to clarify this more.
 

MZKM

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I’ve talked to Dan about this as well.

its not as bad as you make it out to be. it’s certainly better than most speakers. Most show a dispersion shift. Often more than one.

in this case, Dan pointed out that the timbre of the speaker is primarily going to be set by the listening window. The listening window and early reflections windows both look very good. I hope to share the data differently at a future date to clarify this more.
Only thing I’m curious about is that their horizontal polar shows the directivity shift but their Spin doesn’t (James‘ does). Just confusing. Their bass in the Spin is not realistic (talking not being omni), so I wonder how their measurements were achieved.

Are their other speakers on sale yet? I can’t find any pricing. The bookshelves look interesting.
 
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amirm

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I think we are saying much the same thing here. The nearfield measurement is also what is in the standard. To be honest, while speaker distortion is many orders higher than mic distortion, I don’t know that it is fair to say you know yours is way less than every speaker. I believe Klippel uses GRAS half inch mics right?
Klippel resells a large set of microphones from different companies with GRAS being one of them. The one I have is from Micrtech Geffel in Germany. It is a 1/2 capsule that has max SPL of 135 dB before clipping. As such it is cruising at the levels I am using it. I have measured some 160 speakers with it and I yet to find any fixed signature of its own on any measurements.
 

amirm

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min my opinion all speakers should be used with subwoofers. It’s always better when done correctly.
Done correctly is a tall order. Basically the user becomes a speaker designer, adding another "way" to the main speakers. For two channel listening if possible I like to see full-range speakers and not mess with subs. For home theater, the sub is mandatory anyway so might as well sign up for it. But for 2-channel, my preference is without.
 

Matthew J Poes

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Klippel resells a large set of microphones from different companies with GRAS being one of them. The one I have is from Micrtech Geffel in Germany. It is a 1/2 capsule that has max SPL of 135 dB before clipping. As such it is cruising at the levels I am using it. I have measured some 160 speakers with it and I yet to find any fixed signature of its own on any measurements.

oh I see. I didn’t realize they had that range of options.

I wasn’t trying to suggest I knew it was an issue. I just know it’s nearly impossible to measure microphone distortion below the point of the capsule overloading. Nobody really knows their mics distortion in its linear range. It’s almost always less than the source.

the tests I have seen used special calibrators where the distortion was both very low and known. They then measure it with mics and see if the calibrator distortion comes through or something worse. In one case one is the GRAS mics was absolutely worse than the calibrator and was suggesting something like .2% for the 2nd harmonic was its limit. But that would have been at that specific frequency at I believe either 94 or 114dB. I really don’t remember exact details and I am known to sometimes remember these things conveniently. So it could have been .02% at 120dB and I just don’t remember the details right.
 

Matthew J Poes

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Done correctly is a tall order. Basically the user becomes a speaker designer, adding another "way" to the main speakers. For two channel listening if possible I like to see full-range speakers and not mess with subs. For home theater, the sub is mandatory anyway so might as well sign up for it. But for 2-channel, my preference is without.

I understand the point you are making. But it is often not possible for 2 speakers in a typical room to have bass as smooth and good as can be had using multiple subwoofers. I won’t say it’s never possible, but in the 100’s of rooms I’ve now measured or received measurements from, it’s only been true in a tiny fraction of them. They all have modal and SBIR issues. There are very often constraints on where the speakers and listener can be placed. Subwoofers fix that.

on top of that, unless the speakers have actual subwoofers built in, it’s pretty rare that a full range speaker can reproduce bass as well as even a fairly cheap subwoofer can.

but I’ll also agree that properly integrated is hard for a lot of people. When I get new clients, more often than not, the main issue they have is a badly integrated subwoofer. I’ve even most clients because they hired me to fix their acoustics and upgrade their system. But a simply change tot heir processor settings resolved the actual issue. Which I guess is fine. So clearly a lot of people have problems integrating subwoofers. It’s hard to do. Hell, Gene argues with me all the time over it.
 

fluid

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1. Are you aware of any good research on preferred vertical beamwidth and/or ceiling and floor reflection preferences.

I don't know that there is any research that is quite that specific but some of the best research into the perception of reflections was done by Soren Bech in conjunction with KEF and B&O in the late nineties. I have attached the pdf's to save searching for them (I had to zip one to get it below the file size limit)
 

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echopraxia

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I understand the point you are making. But it is often not possible for 2 speakers in a typical room to have bass as smooth and good as can be had using multiple subwoofers. I won’t say it’s never possible, but in the 100’s of rooms I’ve now measured or received measurements from, it’s only been true in a tiny fraction of them. They all have modal and SBIR issues. There are very often constraints on where the speakers and listener can be placed. Subwoofers fix that.

on top of that, unless the speakers have actual subwoofers built in, it’s pretty rare that a full range speaker can reproduce bass as well as even a fairly cheap subwoofer can.

but I’ll also agree that properly integrated is hard for a lot of people. When I get new clients, more often than not, the main issue they have is a badly integrated subwoofer. I’ve even most clients because they hired me to fix their acoustics and upgrade their system. But a simply change tot heir processor settings resolved the actual issue. Which I guess is fine. So clearly a lot of people have problems integrating subwoofers. It’s hard to do. Hell, Gene argues with me all the time over it.
I still think people vastly underestimate the importance of spatial location difference between the subwoofer and mains, because aside from extremely deep and extremely steep crossovers, the crossover usually used still means that a lot of very localize-able frequencies will be very audible from the subwoofer. To those whose ears are very sensitive to spatial cues like myself (which is also probably why I enjoy wide beam speakers), this bass location discontinuity effect can be very disconcerting.

Example: I put a lot of work into integrating dual subs with my Salon2’s in several rooms. I’ve tested sweeps via REW across a wide range of delays to find the one with the strongest and smoothest response at the listening positions. Then I EQ the subwoofer to be as flat as possible, EQ the speakers bass to be as flat as possible, and then try various crossovers to maximize the in-room strengths of each. And yet I still find that for music enjoyment, listening full range (which is flat to 20hz in my room) still gives the most pleasing results in terms of bass whose integration is beautifully continuous and seamless, more so than any subwoofer integration I’ve ever heard anywhere. So my subjective findings here agree with @amirm even though I had no idea his observations were so similar as well until now.

The only exception to this is my GLM-calibrated Genelec subs when I use a very low crossover frequency. If the crossover frequency is higher than 50-60hz, I still notice the location discontinuity between sub and main speakers, even with the very steep crossovers that GLM uses. I’ve also found that if I center the sub between the two speakers, I don’t notice a location discontinuity even with fairly high crossovers.
 
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warthor

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It appears these speakers rightly are getting a lot of attention! Sadly, they are a bit out of my price range. Do the R5t warrant some attention as next-best? It would appear they will be less price and also have the THX Dominus Certification (R5t Tower — Perlisten Audio , scroll to the bottom).

What do you think of this model as a lower-cost (one model down) version of the S7T?
 

richard12511

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I don't know that there is any research that is quite that specific but some of the best research into the perception of reflections was done by Soren Bech in conjunction with KEF and B&O in the late nineties. I have attached the pdf's to save searching for them (I had to zip one to get it below the file size limit)
Thanks. Just got back home from vacation, but will read later. You’ve given me a lot of great material to read lately :)
 
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