Harmonic distortion at 96db

[MAB]

Is there any small,medium sized bookshelf speaker (under 8"), that can do 96db peak down to 60-80hz with no noticeable harmonic distortion and doesn't cost several 1000 euros,pounds,dollars for a pair ?

This is an age-old problem, governed by Hoffman's Iron Law.

1. Deep bass
2. Small enclosure size
3. High efficiency

You can't have all three, they are in physically mutually-exclusive. In your OP you specify small with under 8" woofer. You also said cheap but that implies small, so double clear on that.

As a result, your criteria can result in a design with high sensitivity but no deep bass, or a speaker with deep bass but poor sensitivity.

One example of deep bass in a small speaker is the March Sointuva, which has an F3 of 40 Hz. This is great bass extension for a bookshelf, it uses one of the most the most advanced 6.5" bass driver plus two passive radiators (very expensive). As a result of the Iron Law, it's measured sensitivity is around 80dB/2.83v/1m! And it has 1% distortion at 50Hz at 86 dB, growing to 10% at 96 dB. And it compresses badly above 96 dB at 1 meter, so no way this is a good candidate for playing loud or in a large room where it is quickly power-limited. Even this awesome example has to sacrifice bass distortion and limit the output to get the deep response. It could be built larger, with additional tradeoffs.

Monitor Audio Bronze 100 might be a good candidate. I scored a used set of the 6g's a while back for $250 shipped on ebay, they just ended up being a bit too large for my room. The newer 7g model should be very similar.

This is an example of a different set of tradeoffs than the Sointuva. The Monitor Silver 100 was reviewed here and looks really nice. It does have higher measured efficiency around 88dB/2.83V/1m, it does so by limiting the bass to F3 to ~80 Hz. To be clear it has much worse distortion % at 50 Hz than the Sointuva, but also has reduced output down low so not an audible problem. It still has to obey the laws of physics, cone excursion at 96 dB dictates distortion, and it has some additional resonances/artifacts starting to pop up at 96 dB, perhaps really advanced drivers like the PuriFi units in the Sointuva would help, but this level of distortion is no hill to die on since there are so many other things that are more audible than even 10% bass distortion.

Limiting the bass more would push the efficiency, which would have the effect of lowering the driver excursion at a given SPL, which would lower the distortion (all other things being equal, it's that simple). But most people won't accept the sound of a bookshelf with F3 above 100 Hz. So we are hemmed in by the laws of physics with bookshelf speakers like the Monitor and the March, which both have acceptable distortion unless you want loud. Speaker distortion has gradually dropped on my priority list since unless a driver completely overdriven it isn't that audible, and hearing subtle distortion at loud volumes above 90 dB becomes exceedingly difficult for us and even moreso if the distortion is in the bass.

 

[Mort]

Another like that is the Philharmonic audio BMR monitor. 83db sensitivity

 

[phoenixdogfan]

Perhaps a pair of Kef R3's or R3 Meta might come close to filling your bill. The R3's in particular show up from time to time in Warehouse clearance sales for under $1200 pr. As shown in this graph from EAC even at 100 hz, THD is at or below (-40 db) which translates to 1 percent. At 60-80 hz THD is at or below (-30 db) or 3 percent. Both numbers represent inaudible levels of THD for those frequencies inasmuch as human hearing is very insesitive to distortion of those frequencies. The R3 Meta should be just as good, albeit at a higher price...

 

[MAB]

Another like that is the Philharmonic audio BMR monitor. 83db sensitivity

I think you are thinking of the Philharmonic Affordable Accuracy Monitor.
It is another great sounding speaker, following Hoffman's Iron Law to tiny footprint.

Even the larger BMR follows The Law. The BMR isn't even low distortion compared to some competitors, but still sounds fantastic.

 

[kharan]

Around $1k, there's the Wharfedale Linton, probably one of the best deals in Audio of the past few years.

If you want low distortion and bass, and you don't want to pay for a top of the line driver, you'll probably need a big box.

 

[staticV3]

Another like that is the Philharmonic audio BMR monitor. 83db sensitivity

KH120II has a good 10dB lower THD across the board:


And it costs less

 

[staticV3]

Around $1k, there's the Wharfedale Linton, probably one of the best deals in Audio of the past few years.

If you want low distortion and bass, and you don't want to pay for a top of the line driver, you'll probably need a big box.

Same distortion as the much cheaper, much smaller Swissonic A306, so hardly competitive in that regard.

 

[EngineerNate]

KEF Q Concerto Metas are pretty close to this goal as well.

 

[staticV3]

KEF Q Concerto Metas are pretty close to this goal as well.

See one post above. Concertos have identical THD in the bass.

 

[dfuller]

Low bass distortion is largely inaudible. Staying below ~3% down to meaningful bass frequencies is exceptional performance. Besides that, remember that this is for one speaker, free-field. This is not how speakers are used in reality, with room reinforcement and a second speaker increasing SPL by a lot.

It's either expensive, huge, or more often, both.


$9,000 US/pr Genelec S360. 10" woofer. Big speaker, and expensive. Fulfils your low bass distortion criteria, even at 96dB no individual harmonic in the bass region is above 2.5%.

Neumann KH420 stays below 3% down to 70hz at 96dB. $11,000/pr, even bigger than the S360.

The only speaker I can think of that can do 96dB/1m that isn't nearing 5 figures and isn't 30L or more internal volume is the KH150, but that's still $3500/pr, and 96dB is about as loud as it can go at all - the limiter is very aggressive because the driver design is one with very "loose" suspensions compared to typical high excursion drivers.

 

[gasolin75]

Here they review the Monitor Audio Bronze 100 (germain review)
Erstaunlich hohe Pegel Reserven = Surprisingly high level reserves, they give it max score for sound and distortion but whathifi trash them (couldn't find a better discribtion word in english,danish than trash)

They also wrote (translated from german to english)

And even at the significantly higher level of 101 dB, the distortion of the mid-bass driver (the tweeter does not distort at all at this level!) remains in the moderate range.

Erster Test: Kompaktbox Monitor Audio Bronze 100 - LowBeats

Der britische Lautsprecher-Spezialist Monitor Audio hat jüngst die 6. Generation seiner Mittelklasse

www.lowbeats.de

Monitor Audio Bronze 100 review

These standmounters fall short of the expected greatness

www.whathifi.com

 

[EngineerNate]

Don’t take WhatHiFi seriously.

 

[dfuller]

Here they reveiw the Monitor Audio Bronze 100 (germain review)
Erstaunlich hohe Pegel Reserven = Surprisingly high level reserves, they give it max score for sound and distortion but whathifi trash them (couldn't find a better discribtion word in english,danish than trash)

They also wrote (translated from german to english)

And even at the significantly higher level of 101 dB, the distortion of the mid-bass driver (the tweeter does not distort at all at this level!) remains in the moderate range.

Erster Test: Kompaktbox Monitor Audio Bronze 100 - LowBeats

Der britische Lautsprecher-Spezialist Monitor Audio hat jüngst die 6. Generation seiner Mittelklasse

www.lowbeats.de

This is not the same thing. This is a multitone distortion test, and it primarily (but not exclusively) measures intermodulation distortion. Besides that, 96dB for a single tone is much higher than 96dB for 32 tones (or however many) simultaneously.

 

[voodooless]

This is not the same thing. This is a multitone distortion test, and it primarily (but not exclusively) measures intermodulation distortion. Besides that, 96dB for a single tone is much higher than 96dB for 32 tones (or however many) simultaneously.

If anything, this should be more indicative of what the speaker will do with real music.

These results though, seem unlikely. A bookshelf speaker does not have so little IMD at < 50 Hz.

 

[SlowJim]

The link I shared when I originally mentioned the Bronze 100's included independent Klippel test data. No need to search elsewhere...

 

[gasolin75]

The link I shared when I originally mentioned the Bronze 100's included independent Klippel test data. No need to search elsewhere...

Distortion seems pretty high from 150 hz and down at 95 db

 

[Sir Sanders Zingmore]

If you won’t compromise on the price or distortion requirements then maybe compromise on the “speakers” requirement and get these instead:

Verum Audio Verum 2 Headphone Review

This is a review, listening tests, EQ and detailed measurements of Verum Audio Verum 2 planar magnetic open back headphones. It was drop shipped by the company and costs US $425. As you see, this is a "high bling" headphone when it comes to design with so much intricate details. It is a bit...

www.audiosciencereview.com

 

[gasolin75]

Im not at all gonna buy headphones + i don't have a headphonoe input for one

I never use one for hifi in my home more than 35 years and not gonna do it

I havn't wrote im interested in buying speakers that can do 96db (peak) with very low harmonic distortion

 

[sigbergaudio]

If you want bookshelf speakers with low distortion in the bass, the best solution would probably be to pair them with a subwoofer or two, and cross them over high.

 

[DanielT]

The harmonic distortion through the midrange is among the lowest of the speakers I have measured, THD ~0.2% @ 100dB 800Hz - 2kHz!

MTG Designs - VBS-6.2

The Design: A value oriented compact 6" 2-way with a horn loaded compression driver and excellent sound quality and output above 100hz. Best used as surrounds or compact mains in a home theater or where a small high output speaker is needed when subwoofers will be used to fill in the bottom end.

www.mtg-designs.com

Plus a good integration with a good subwoofer, or even better a three-way speaker together with that DYI two-way speaker.
Choose bass drivers with good enough specs to reach your set criteria.
High SPL with low distortion that goes really far down frequency = a lot of $
(plus probably large physical space)
Edit:
Maybe even three-way speakers with sub may be needed. Depends on requirements, plus the usual consideration of physical space and $.

If you just want a regular traditional small hifi bookshelf speaker, then fine. BUT they have their limitations. If you want to play really loud relatively distortion-free full range, you will have to consider other solutions.