Buchardt S400 Speaker Review

[Sonny1]

Ok, how about comparing S400 with KEF Q100?

Why compare the Q100 with the S400? The Q100 is a budget minded speaker that sells for much less. The KEF R3 and the new JBL monitor are both around the same price category and both seem to outperform the S400.

I like the looks of the S400 and the fact that they are from a new exciting company. The directivity mismatch and the paper thin resonant cabinets are a disappointment for a speaker in this price range. I was considering the S400 until I learned they don’t play well at higher SPLs (compared to the KEF and JBL competition). The cheap cabinet and design flaws are just icing on the cake.

Hopefully, the company will correct the design and improve the product as a result of the testing. Maybe do what Schiit did when their product flaws were identified by ASR.

 

[QMuse]

Why compare the Q100 with the S400? The Q100 is a budget minded speaker that sells for much less. The KEF R3 and the new JBL monitor are both around the same price category and both seem to outperform the S400.

It was in the context of THD at LF and only to tease @andreasmaaan a little!

 

[amirm]

We find Amir’s contour plots performed at 66cm in nearfield not very useful.

Thanks for the detailed comments Mads. Much appreciated.

On this point, it is not material. All the visualizations are in far-field. Changing the distance parameter simply changes the SPL values, not the graph. Far field means 1/r reduction in SPL occurs and that is that. For this graph, we don't care what the SPL values are as absolute.

What can make a difference is angular resolution. I am not in front of my workstation but I may have run the visualization at 1 degrees rather than default of 5. This brings out more details in the soundfield than 5 degree would although both are much better than what others publish.

 

[amirm]

In our opinion it is NOT the right use of the NFS fitting-system, to judge where the correct acoustic axis for the product is. According to NFS measurement manual – in order to get the best possible fitting for the system, you should choose the driver playing the highest frequencies as your starting point for the spherical harmonics fitting. This will in most cases be the tweeter. So - from our perspective this result will always be the case – and you will always get bad result when a different point is chosen. This just says something about how the Klippel fitting function is implemented, nothing about the actual speaker. To judge the acoustical listening axis, the vertical contour plot will give you the answer, if reference axis is chosen properly in Klippel hardware setup.

This is understood. And I noted it in the review. Using your recommended axis did lower fidelity of the sound field extrapolation but that was limited to higher frequencies. In lower band where we saw the directivity issues, it was just as accurate as the tweeter center. It had the benefit then of showing the reference axis being your recommended one so there would be no objection that I did not use the correct manufacturer reference axis.

 

[napilopez]

The change in crossover point Mads explained is notable and explains some of the differences between my measurements and Amir's. I understand the reasoning for not advertising it, but going forward it would be good to have a note on the site for such changes. But at least now I know I didn't screw up my measurements too much .

I'm pretty sure I reviewed one of the older units, since all my dips are around 2kHz not 2.6. I'd personally take the higher crossover as it won't exacerbate the 2kish interaural crosstalk dip as much with typical speaker positioning, but obviously that depends on how your speakers are setup.

But I'll recuse myself from posting my measurements for comparison now as it is in effect a slightly different speaker. At least when it comes to the nitpicking we do around here.

That said, with regard to directivity plots, I do think the lack of normalization to the on-axis is affecting perceptions a bit too. If you don't normalize to the on-axis, the plot will simply exacerbate the dip that is already present on the on-axis data.

Using Amir's own data, normalized to the on-axis and scaled to be the same size, here's the VituixCAD-generated polar plot:

And without the contour lines:

Dip is still there and a bit less than ideal in Amirs data regardless, but IMO doesn't scream 'DIRECTIVITY MISMATCH!' the same as when not normalized.

This is understood. And I noted it in the review. Using your recommended axis did lower fidelity of the sound field extrapolation but that was limited to higher frequencies. In lower band where we saw the directivity issues, it was just as accurate as the tweeter center. It had the benefit then of showing the reference axis being your recommended one so there would be no objection that I did not use the correct manufacturer reference axis.

I believe Mads is differentiating between the expansion point for the klippel math, which as we all agree should be the tweeter, and the acoustical listening axis, I.E. where the speaker is designed to sound best and the point from which the other graphs are calculated relative to. I.E. The mic should be set to the tweeter as you do, but there's a change to way the listening axis in the klippel software?

Not a huge thing and there's the head in a vice argument, but just pointing it out as it relates to the appearance and interpretation of the data.

 

[GelbeMusik]

As a DIYr, these kind of statements befuddle me. Look, we all know if you have the time and the skill you can easily build nearly any manfucaturered product for cheaper than retial cost.

If You refer to the price tag of the woofer I gave, it's true. I mentioned it as to emphasize the effort it obviously took to assemble all of the parts. Buchardt asks for 1.8k a pair, which only shows how difficult it must have been to get it right. Still there are compromises. If 1000$ are the supplieres costs for building a pair--that would be quite a lot, selling some 1200 pairs would yield some revenue.

I'm o/k with a professional endevour. But looking into said compromises, regarding this individual design, I would rather look for different compromises. It doesn't compete too well against a Genelec for instance, to my personal liking of course.

 

[hardisj]

If You refer to the price tag of the woofer I gave, it's true. I mentioned it as to emphasize the effort it obviously took to assemble all of the parts. Buchardt asks for 1.8k a pair, which only shows how difficult it must have been to get it right. Still there are compromises. If 1000$ are the supplieres costs for building a pair--that would be quite a lot, selling some 1200 pairs would yield some revenue.

I'm o/k with a professional endevour. But looking into said compromises, regarding this individual design, I would rather look for different compromises. It doesn't compete too well against a Genelec for instance, to my personal liking of course.

I misunderstood your post. I thought you were saying "it only costs $80 per woofer so why not just DIY something cheaper". People tend to forget the time and experience it takes to design a proper crossover. Not saying it is rocket science. But it isn't trivial.

 

[Voo]

can klippel measure speakers in stereo? I have read all of Dr. Tooles book and the harman science on mono. but something about music recorded in stereo...it can be amazing.

 

[andreasmaaan]

This one looks good:

It has a larger woofer and costs 3 times more.

 

[ctrl]

Any comment on relatively high THD at around 90Hz?

The cause is probably the passive radiator. The passive radiator has a strong resonance around 200Hz.

This can lead to increased HD3 around 70Hz - which fits quite well with Amir's measurement.

Furthermore, the 200Hz resonance of the passive radiator could contribute to increased HD2 at 100Hz - here, too, a small peak is visible.

As @Mads Buchardt had written, the passive radiator was deliberately chosen to
⦁ Avoid port designs for compression and noise reasons

Whether this decision really brought so many advantages is a matter for everyone to decide for themselves. As a BR design, the low frequency response would probably be less good.

But at low frequencies harmonic distortions are masked quite well. At 80-90Hz, for example, HD2 is masked up to almost 30% HD at 90dB.

hifi-selbstbau.de

 

[thewas]

It has a larger woofer and costs 3 times more.

6,5" two-way Genelec M040 (I got my pair for less than 1000€ new, now discontinued)

 

[richard12511]

Why compare the Q100 with the S400? The Q100 is a budget minded speaker that sells for much less. The KEF R3 and the new JBL monitor are both around the same price category and both seem to outperform the S400.

The R3 did, but the S400 slightly outperforms the JBL.

 

[Voo]

harman science wrote off stereo measurements 40+ yrs ago...surely we have better science?

 

[andreasmaaan]

6,5" two-way Genelec M040 (I got my pair for less than 1000€ new, now discontinued)

View attachment 61036

Looks pretty similar to the S400 to me (the trace marked "100dB" is actually about 97-98dB in the bass, which is a comparable level to that at which the S400 was measured).

EDIT: and ofc the woofer of the M040 is larger, too.

EDIT2: I'm sure with enough digging someone will come up with a 6" two-way costing under €1k per speaker with slightly better bass distortion performance than the S400.

The essential point though, is that it's very difficult to do this in a 6" 2-way at this price point and do everything as well in the midrange as the S400's woofer does.

 

[thewas]

Looks pretty similar to the S400 to me (the trace marked "100dB" is actually about 97-98dB in the bass, which is a comparable level to that at which the S400 was measured).

As we know the limit at which distortion rises is very abrupt, Amir writes the distortion measurement was at 96dB and then the S400 bass distortion components are around 75-80dB while on the Genelec they are around 60 dB at the 95dB measurements and only rise to similar levels at the 100dB measurement.

EDIT: and ofc the woofer of the M040 is larger, too.

Is it? Its a nominal 6,5" driver which is the same "size class" like the "17" SB drivers, isn't it? And even if it was centimeter larger, it is active competitor from a known company for a significantly lower price, since you (correctly) mentioned the B&W 805 D3 being much more expensive.

The essential point though, is that it's very difficult to do this in a 6" 2-way at this price point and do everything as well in the midrange as the S400's woofer does.

What do you think the SB driver does so much better in the midrange than the Genelec one?

 

[andreasmaaan]

As we know the limit at which distortion rises is very abrupt, Amir writes measurement at 96dB and then the S400 bass distortion components are around 75-80dB while on the Genelec they are around 60 dB at the 95dB measurements and only rise to similar levels at the 100dB measurement.

The "100dB" measurements of the Genelec are actually at 97-98dB in the bass. So yes, assuming (1) no measurement error and (2) that direct comparison is possible despite these two measurements having been taken under very different conditions, the Genelec can produce an additional 1dB or 2dB in the bass than the S400 before distortion rises to similar levels.

I would not call that a significant difference.

I certainly wouldn't place it outside the realm of experimental error, given the very different circumstances under which the two measurements were made.

Is it? Its a nominal 6,5" driver which is the same "size class" like the "17" SB drivers, isn't it?

Yes, in the same class sure. But for an extra 0.5", you might ask for an extra 1 or 2dB of clean bass performance, which is what we seem to get - right?

I should disclose here: I've measured the woofer used in the S400 extensively, and have compared it to many others woofers of its size. I agree that its bass performance is not best-in-class. However, it is at least in the same league as every other 6" I've measured at that price point. Moreover, for use in a 2-way design, I've found it extremely hard to beat owing to its excellent midrange performance.

Finally, I think it should also be noted that, at the drive level @amirm took this distortion measurement (which I calculate was at around 9V), this woofer in this box would have been pushed to just at or just beyond Xmax. What we're looking at is the woofer's performance right at or just beyond its limit. I have no doubt that a slight easing off of drive voltage - even equivalent to just 1 or 2dB lower in output level - would result in distortion charts that look very similar to those of the M040 posted above.

 

[Sonny1]

The R3 did, but the S400 slightly outperforms the JBL.

At lower volume levels perhaps but I can’t live with a speaker that only sounds good at low volume levels. Also, Amirm’s and Dennis Murphy’s subjective comments don’t inspire confidence in this design. For the money, I believe there are much better options.

 

[andreasmaaan]

@amirm, sorry to ask you again to do extra work in this area, but perhaps you'd be willing to take two distortion measurements in future: one at a moderate SPL (83 or 86dB perhaps?) and one at 96dB.

I think 96dB is going to be either at or beyond the excursion limits of most 6.5" or smaller standmounts, which is going to make it difficult to discern much about each speaker's bass performance when driven within its limits.

 

[BYRTT]

Ha ha what a curve interesting thread somewhere being close to a scandale that advertised spin didn't match what Amir analyzed but is those curves really so different, explanation of some differences could be that the first advertised manufacture spin was analyzed using a lower crossover point that now is advertised to be set a notch higher down the road and then there is technical feature that Amir measure on tweeter axis and manufacture curve is probably a curve calculated say 88mm lower in the middle between center of tweeter and woofer.

Below three set of on axis overlays show Amir's curve in black, blue curve is first advertised S400, red curve is this new advertised S400 with a higher crossover point, and orange is @hardisj ground plane measurement that i added to help support Amir looks have a good case for 500Hz resonance area ..

For @napilopez, @Mads Buchardt, and @amirm it could probably be interesting see the 88mm lower microphone position relative to spindata and also added normalized polars:

Back to that irritating resonance that Amir and hardisj can resolute and manufacture can not, for fun in below model i borrowed hardisj nearfield measurement of the passive radiator thanks and inverted its polarity plus a delay of 3110uS:

 

[Juhazi]

This is understood. And I noted it in the review. Using your recommended axis did lower fidelity of the sound field extrapolation but that was limited to higher frequencies. In lower band where we saw the directivity issues, it was just as accurate as the tweeter center. It had the benefit then of showing the reference axis being your recommended one so there would be no objection that I did not use the correct manufacturer reference axis.

Mads's and Amir's verticals have different scales, but here is a gif with same scales. The difference comes from where vertical reference axle is set in NFS.