Dutch & Dutch 8c Review

[Pearljam5000]

Most of the subjective impressions I've read relating to MEG vs Genelec, MEG vs Kii, etc. have been similar to yours(ie the MEG comes out on top). Unfortunately, the measurements I've seen are all incomplete and insufficient to really judge a speaker. The third party measurements I've seen look good, but not Genelec good. We need to get one to Erin or Amir, or maybe ME Geithain could send a sample themselves?

Could it be the full range cardioid response? Even the 8C only controls down to 100Hz, though I've also heard that cardioid doesn't matter under 200Hz anyway, so who knows.

MEG, D&D, Kii, and Grimm are all on my shortlist for my 2.0 channel room. Grimm probably not, since they seem quite overpriced. I'd have to be blown away. I wish MEG speakers were easier to find where I live.

I also disagree with you that they look bad. They're actually some of my favorite speakers, aesthetically.

 

[olivier salad]

That is the d&d

Someone needs to pull this thing apart and measure the amp's performance

 

[Dialectic]

Someone needs to pull this thing apart and measure the amp's performance

Detailed specs are available.

 

[olivier salad]

Detailed specs are available.

I can't find them

 

[hmt]

As to why the high harmonic distortion around 100Hz occurs, I have a "theory" (rather speculation) to offer.
Have only skimmed the thread do not know if my "theory" has already been mentioned - sorry if the answer is yes.

The lateral slots are nothing else than Helmholtz resonators. These are used with the midrange driver to generate phase-inverted sound pressure and thereby produce the cardioid radiation.

The phase-inverted sound must cover a wide frequency range, which means that the tuning frequency of the slots must be relatively high.
You could also use differently tuned slots to extend the frequency range, but don't ask me what exactly happens then. This and my "theory" would all have to be checked and verified at least by simulations.

It would have been interesting if @hardisj had also taken near-field measurements of the lateral slots, that would facilitate a possible explanation.

Since the subwoofers have a crossover frequency of 100Hz, the midrange driver still plays at full sound pressure level below the tuning frequency of the slots. However, this means that the excursion of the midrange driver increases extremely and it therefore generates more HD3.

If then at around 60Hz mainly the two subwoofers generate the sound pressure, the distortion drops to an intermediate minimum.

Actually I think that is the reason why the MEGs use such a large driver. The max output of those is not as high as one would think. The Cardioid design makes them relatively inefficient. I think I a way it creates an acoustic short.

 

[BDE]

Thanks for the measurements, I almost missed this because it was not published on the review page. Will it be possible to show your speaker reviews on the landing page too?
The distortion graphs are easier to catch with percent values or even better like Neumann does (maximum SPL @ 3% and 10% THD).
Did you also investigate how the slots work (e.g., sound pressure, phase and delay in relation to the mid-woofer?
Except from the distortion a nice speaker and in white with the wooden enclosure also nice looking, unfortunatly way too expensive (al least from my point of view).

 

[olivier salad]

https://www.pascal-audio.com/wp-content/uploads/2018/06/S-PRO2_Datasheet-1_20.pdf

Thanks. The measurements aren't great, to be honest. I wonder why they didn't use something better.

 

[Dialectic]

Thanks. The measurements aren't great, to be honest. I wonder why they didn't use something better.

This has been discussed ad nauseam elsewhere on ASR. Better amplifiers were not used because the difference is not audible. Other manufacturers have opted to use the Pascal modules--which were designed for live sound applications but perform well enough for studio monitors--for the same reason.

As an 8C owner, I am glad I didn't pay $5K more for a few more dB of amplifier SINAD that is inaudible.

 

[phoenixdogfan]

I did! Front side first. Unfortunately, that image is to scale.

I kind of like the metal stand look they have, it takes no prisoners.

Kinda look like George Orwell's favorite speakers.

 

[HiFidFan]

Kinda look like George Orwell's favorite speakers.

Dang! So they have a microphone?

 

[JustJones]

Interesting that they chose solid oak for the cabinets. If the speaker is 15” deep, that would make ~14” side panels. As a woodworker, I would expect about 1/4” of seasonal dimensional change in a panel that wide.

The Oak D&Ds I had did have noticable surface cracks. If you have a dry climate might need some furniture oil rubbed on them.

 

[Dialectic]

The Oak D&Ds I had did have noticable surface cracks. If you have a dry climate might need some furniture oil rubbed on them.

Is there a product you recommend? Or a product that D&D recommends?

The initial pair I got had a faintly visible hairline crack in the oak that, within a few weeks, turned into a crack going all the way through the cabinet. It may have been a result of shipping damage. D&D was very responsive about the problem and replaced them with a new pair.

I have not had a problem with the oak on the replacement pair, although my new house (like most dwellings in the United States) has forced-air heating, which tends to be dry.

 

[olivier salad]

This has been discussed ad nauseam elsewhere on ASR. Better amplifiers were not used because the difference is not audible. Other manufacturers have opted to use the Pascal modules--which were designed for live sound applications but perform well enough for studio monitors--for the same reason.

As an 8C owner, I am glad I didn't pay $5K more for a few more dB of amplifier SINAD that is inaudible.

The difference isn't $5K, NC502MP is probably $500 or so, I guess they need 2 of those per speaker. And ICEpower is much cheaper than Hypex and measures better than Pascal.

 

[Kvalsvoll]

As to why the high harmonic distortion around 100Hz occurs, I have a "theory" (rather speculation) to offer.
Have only skimmed the thread do not know if my "theory" has already been mentioned - sorry if the answer is yes.

The lateral slots are nothing else than Helmholtz resonators. These are used with the midrange driver to generate phase-inverted sound pressure and thereby produce the cardioid radiation.

The phase-inverted sound must cover a wide frequency range, which means that the tuning frequency of the slots must be relatively high.
You could also use differently tuned slots to extend the frequency range, but don't ask me what exactly happens then. This and my "theory" would all have to be checked and verified at least by simulations.

It would have been interesting if @hardisj had also taken near-field measurements of the lateral slots, that would facilitate a possible explanation.

Since the subwoofers have a crossover frequency of 100Hz, the midrange driver still plays at full sound pressure level below the tuning frequency of the slots. However, this means that the excursion of the midrange driver increases extremely and it therefore generates more HD3.

If then at around 60Hz mainly the two subwoofers generate the sound pressure, the distortion drops to an intermediate minimum.

I can not comment on how the D&D works specifically, there are so many variables involved, many of which are neither obvious or visible from the outside.

However, the general behavior of a cabinet with acoustically damped ports are different from a typical bass-reflex helmholtz type enclosure. The sound radiated from such damped ports generally has a quite wide frequency range where phase is flat at -180 degrees compared to the output from the front of the driver cone. Such a system is tuned by choosing both level, frequency response and position and timing of the output from those damped ports. A simulation model run in a software simulator is the best way to design this system properly.

Some of the distortion can be attributed to the driver in combination with reduced efficiency due to cancellation from the port output, but there are other significant sources of nonlinear distortion in such a system, and it gets worse when you reduce physical size.

The complexity of designing such a speaker is very different from a typical sealed enclosure.

 

[JustJones]

Is there a product you recommend?

The initial pair I got had a faintly visible hairline crack in the oak that, within a few weeks, turned into a crack going all the way through the cabinet. It may have been a result of shipping damage. D&D was very responsive about the problem and replaced them with a new pair.

An oil based polish like Howard or Boiled linseed oil.

https://www.amazon.com/Howard-Produ...ocphy=9014248&hvtargid=pla-307126338215&psc=1

 

[617]

An oil based polish like Howard or Boiled linseed oil.

https://www.amazon.com/Howard-Produ...ocphy=9014248&hvtargid=pla-307126338215&psc=1

Consult D&D, who knows what finish they used, could be incompatible with BLO.

 

[dc655321]

The lateral slots are nothing else than Helmholtz resonators.

I would say more dipole than resonator. Take a look at dipole/open baffle designs and compromises.

 

[RobL]

An oil based polish like Howard or Boiled linseed oil.

https://www.amazon.com/Howard-Produ...ocphy=9014248&hvtargid=pla-307126338215&psc=1

Conditioner won’t stop seasonal movement in the wood. Where I live, the humidity variation from winter to summer would be very hard on these cabinets. They will be especially prone to developing cracks if any internal bracing is glued across the grain of the solid wood. Plywood with veneer is a much better choice in this application. I also wonder if dimensional variation season to season would cause tuning issues in a speaker box.

 

[Dialectic]

Conditioner won’t stop seasonal movement in the wood. Where I live, the humidity variation from winter to summer would be very hard on these cabinets. They will be especially prone to developing cracks if any internal bracing is glued across the grain of the solid wood. Plywood with veneer is a much better choice in this application. I also wonder if dimensional variation season to season would cause tuning issues in a speaker box.

I believe I heard there is Baltic birch beneath the oak.

 

[JustJones]

Conditioner won’t stop seasonal movement in the wood. Where I live, the humidity variation from winter to summer would be very hard on these cabinets. They will be especially prone to developing cracks if any internal bracing is glued across the grain of the solid wood. Plywood with veneer is a much better choice in this application. I also wonder if dimensional variation season to season would cause tuning issues in a speaker box.

The best thing is trying to keep humidity fairly consistent. Where I live a whole house humidifier in the winter would help. I sold mine and got Genelec 8351b I might be one in a million but I like the Genelec better.