Mesanovic CDM65 Studio Monitor Review

[Halbknapp]

Well, it is possible to "force" a deeper bass out of speakers. I thought of: Linkwitz transform.
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One moment, please...

Nothing I've tried myself. Should work but it should be at the expense of lower SPL for the same distortion level, or higher distortion at the same SPL. Compromises in other words. If this is the case, I am not completely sure, but intuitively I can guess that this is the case.

Edit: sigberg was faster to answer.

Linkwitz transform costs headroom in deeper bass (it is a specific variant of deep bass boost) The upper bass does not change much but as the speaker is forced to play deep bass it would naturally not do any content that has this deep bass will cause much more excursion, amplifier and voice coil heat.
But as long as you would not play too loud you use up otherwise unused possible excursion for lower bass output without much downside.

Some active hifi speakers do a variable bass extension but revert and give up on deep bass to limit excursion on high output levels.
In studio speakers this is disputed as the listener would be fooled to misjudge the bass if playing louder volume.

 

[rirelien]

I'd just like to highlight this comment - a manufacturer that gives specific technical advice on DIY, especially when it would theoretically compete with their product, shows confidence (in their product and expertise) and good faith toward the community.

You don't see a lot of brands sharing this level of detail on how to build a good speaker. Insecure brands think sharing details will undermine something... the enlightened ones know better.

Absolutely agreed!

There are others here who are also quite generous with their time and expertise, even when it would appear it’s not always in their narrow personal interest.

It’s really appreciated and visible, and for some of us who are potential customers it speaks very strongly.

Thank you.

 

[anphex]

Isn't the bass distrtion way too high considering it has two extra side woofers?

 

[Ilkless]

Isn't the bass distrtion way too high considering it has two extra side woofers?

It extends much lower than the vast majority of speakers that size measured here. Easy to high pass this at 50Hz and get a pretty picture

 

[staticV3]

Isn't the bass distrtion way too high considering it has two extra side woofers?

The side woofers are used to cancel out bass response to the rear.
Afaik, they don't contribute to SPL.

 

[holdingpants01]

The side woofers are used to cancel out bass response to the rear. They don't contribute to SPL.

Not really, the cardiod pattern start at 150Hz or so, below that they are just normal bass woofers 2x 6.5" which would be about 9" in a single woofer, neither big nor small. The THD results at 96dB are about the same as in KH310 with similar woofer size and closed box, this is nothing weird, but the distortion at 86dB and lower could be concerning

 

[Halbknapp]

The side woofers are used to cancel out bass response to the rear.
Afaik, they don't contribute to SPL.

The side woofers cancel a bit of lower midrange and upper bass but then take over and play all the lower parts alone.

I made a similar speaker where the side woofers really only cancel but that's really a waste of bass output - the mesanovic don't do that.

 

[Halbknapp]

Please also note that it is a closed design. 2 closed 6,5" Woofers is not bad but also not a whole lot to play very deep bass. Benefit is that there really is no midrange leak from the port at all.

 

[Hart]

Side firing woofers seem to make good sense for narrow tower speakers that everyone seems to make today. I am not sure why they are not implemented more often as it is hard for a "fuill range" speaker to provide real bass with 5 or 6 inch drivers. Certainly there is enouugh cabinet volume to support it. Is it a directional issue? Aerial Acoustics had an early version, the 8, seemed like a good idea but it did not catch on.

 

[richard12511]

Almost $1000 more expensive than the KH150 while having fewer controls and worse distortion? Looks like a scam

You could argue 99.9% of speakers as a scam by this metric

Even still, I’d argue it provides a comparable value to the KH150, as it provides improved directivity.

 

[Mtbf]

Without a doubt these are excellent speakers. When someone mentions Buchardt, they are actually more comparable to the Buchardt A500’s (or better the A500 SE’s: higher SPL), although the A500’s are a 2.5-way design and the CDM65’s are 3-way, and the Buchardt only has one backward firing woofer. They use the same built-in Platin amplifier, both in a sealed enclosure.

The Buchardts can also be configured as cardioid speakers, if you choose the cardioid ‘mastertuning’ (but thus become 2-way’s). However that reduces the low bass output, which actually is so attractive about the A500 SE’s. I don’t know whether this is also the case with the CDM65’s, if one would compare the ‘standard tuning’ to the ‘cardioid tuning’, at least this isn’t apparent in Erin’s data.

The one thing that bothers me to some extent are the used amplifiers. They get reasonably hot, up to 56 degrees Celsius (measured from the outside after a few hours use), in a sealed enclosure. Compare that to the passively ventilated amplifiers of the excellent Neumann KH150’s. Or Dutch & Dutch, who use Pascal class-D amplifiers in their 8C’s, known for their reliability. In the mean time Platin refuses to sell these amps to individuals..

 

[anphex]

I see a lot of people mentioning "cardioid" design. Where does that come from? From what I know a cardioid design would show as far less back or sideward radiation of the bass, thus focussing it to the front. In this case, the radiation measurement looks mostly like any other speaker, only at the range between 100-200 Hz looks a little more focussed to the front than other average speakers. Is that worth it the trade off in bass cleanlyness?

 

[kyuu]

I see a lot of people mentioning "cardioid" design. Where does that come from? From what I know a cardioid design would show as far less back or sideward radiation of the bass, thus focussing it to the front. In this case, the radiation measurement looks mostly like any other speaker, only at the range between 100-200 Hz looks a little more focussed to the front than other average speakers. Is that worth it the trade off in bass cleanlyness?

That's a matter of some debate, but many would say yes. Reducing the amount of room interaction in the lower frequencies, where the room interactions cause the most trouble, might seem to be a worthwhile trade off for more distortion in that range which can often be far less audible.

Myself, I prefer the solution of making the baffle somewhat larger, but that involves another set of trade-offs.

 

[holdingpants01]

I see a lot of people mentioning "cardioid" design. Where does that come from? From what I know a cardioid design would show as far less back or sideward radiation of the bass, thus focussing it to the front. In this case, the radiation measurement looks mostly like any other speaker, only at the range between 100-200 Hz looks a little more focussed to the front than other average speakers. Is that worth it the trade off in bass cleanlyness?

right, by that metric JBL M2 is cardioid as well without even trying

 

[thewas]

right, by that metric JBL M2 is cardioid as well without even trying

Which is one of the advantages of such large baffles and drivers but getting into these qualities in a compact size and price needs the discussed sophisticated solutions so I find such approach definitely justified.

 

[dfuller]

Cardioid designs basically gets you the radiation behavior of a large baffle, large driver speaker, while not being huge. I will remind you that the M2 is a 15"(!) woofer.

 

[ShadowFiend]

right, by that metric JBL M2 is cardioid as well without even trying

Yes, but JBL use 15 inch woofer in 510 mm baffle, while CDM65 has just 210mm baffle. That is a completely different category. And if a speaker configure to cardioid pattern with 15" driver, the cardioid can be as low as 70-80 Hz.

 

[holdingpants01]

Yes, but JBL use 15 inch woofer in 510 mm baffle, while CDM65 has just 210mm baffle. That is a completely different category. And if a speaker configure to cardioid pattern with 15" driver, the cardioid can be as low as 70-80 Hz.

I'm not saying they are in the same category, just that no one says JBL M2 are cardioid even if their pattern look somewhat similar. I admire the effort and design of CDM65 but in my opinion it's a stretch to call them cardioid, however justified because there's no better marketing name for what they do

 

[deni]

I'm not saying they are in the same category, just that no one says JBL M2 are cardioid even if their pattern look somewhat similar. I admire the effort and design of CDM65 but in my opinion it's a stretch to call them cardioid, however justified because there's no better marketing name for what they do

We refer to the CDM65 as a controlled directivity monitor (CDM). The specific tuning happens to be called cardioid since it seemed the most appropriate name for it. I should also point out that we can create tunings that offer even more rejection to the sides and rear, but this would come at the expense of increased distortion in the 150-400ish Hz range. The rejection and distortion would be similar to the Kii Three. We opted with the current tuning to keep the distortion profile similar to the "standard" tuning.

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[Blockader]

right, by that metric JBL M2 is cardioid as well without even trying


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A large baffle combined with large drivers can exhibit a cardioid-like dispersion pattern.

The size of the driver and the baffle determines the frequency at which diffractions begin to widen the dispersion pattern. If there is a waveguide or a diffraction slot, they also modify the diffractions.