# DEQX Systems



## Gerhard Westphalen (Jun 29, 2017)

Not sure if this should go in the gear review section but I just wanted to share my experiences with DEQX.

I got one with the new speakers I bought as they require it and are tri-amped with no crossovers. I was fortunate enough to get an amazing deal on a used HDP Express II which normally sell for $3500. If you plan on using it as a crossover instead of just in the full range mode then you should have them calibrate it for you remotely which I believe is around $500. It's not too complicated to use but is complicated to know exactly how much to correct in order to get the best results.

My new speakers won't be arriving for a while as they need freight shipping so I decided to put the DEQX on my Dynaudio BM5 mk3. It was my first time being able to see what it's actually doing (since I can't bypass it on my new monitors are they need it for the crossover). I also wanted to start learning to use it. It took quite a bit of tweaking to get right and this was with no crossovers involved.

Is this $3500 thing worth it on a $700 speaker? Absolutely! I'm stunned at what it does. At the most basic level it has a room EQ which does what I was doing with Reference 3 but this does so much more. It corrects anomalies in the speaker such as the phase and group delay. Suddenly everything is in focus. With more intimate chamber scores it sounds amazing. I don't want to hear my Dynaudios without it now.

I don't know how everyone isn't using this (aside from the cost). I think that anyone doing any serious mixing should consider it. It made my fairly cheap speakers sound like some of the best speakers I've ever heard (certainly above the normal $5000ish/pair normally found in studios). I would choose these over something like un-DEQX-ified ATCs or Barefoots.

I'm not sure how this compares to the Trinnov but I think it's similar. The Acourate programs seem to do something similar for a much lower price but that seems more complicated to use and requires you to route your audio internally through it (or run it on a separate computer as Bob Katz does).

Feel free to share your experiences with these sorts of systems...

I, for one, don't want to have an un-DEQX-ified studio ever again regardless of what speakers I'm using. Is it overpriced? Ya, probably, but I'd say it's no different from the UAD stuff. It's nothing but some SHARC chips (although some of these have really nice converters). What you're really paying for (aside from markup) is the software it's running.


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## muk (Jun 29, 2017)

Interesting. I have never used nor heard DEQX or Trinnov. I only demoed some of the lower cost options. Have you tried Dirac Live? I found it very good and easy to use. Liked it much better than Sonarworks. Would be interesting to hear how it compares to DEQX.
In the end I went with a completely free solution: Room EQ Wizard for the measurements, and Python Open Room Correction (PORC) for the drc. It is a nightmare to set up (PORC doesn't even have a gui and runs on cmd only). No ease of use whatsoever. But the quality of the correction is outstanding. It corrects not only frequency, but time domain/phase as well. The imaging became a lot clearer, the phantom middle is well defined, and voices suddenly sounded human instead of muffled. It is no replacement for proper room treatment and good speakers, but it certainly adds to it. In any case digital room correction is something well worth checking out.


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## Gerhard Westphalen (Jun 29, 2017)

muk said:


> Interesting. I have never used nor heard DEQX or Trinnov. I only demoed some of the lower cost options. Have you tried Dirac Live? I found it very good and easy to use. Liked it much better than Sonarworks. Would be interesting to hear how it compares to DEQX.
> In the end I went with a completely free solution: Room EQ Wizard for the measurements, and Python Open Room Correction (PORC) for the drc. It is a nightmare to set up (PORC doesn't even have a gui and runs on cmd only). No ease of use whatsoever. But the quality of the correction is outstanding. It corrects not only frequency, but time domain/phase as well. The imaging became a lot clearer, the phantom middle is well defined, and voices suddenly sounded human instead of muffled. It is no replacement for proper room treatment and good speakers, but it certainly adds to it. In any case digital room correction is something well worth checking out.



I'm not exactly sure what the Dirac means by correcting the impulse response but it doesn't seem to correct the group delay which I know is one of the key features of the DEQX or Acourate.

The DEQX also involves taking your speakers outside, far away from any walls, and putting padding on the floor to get as close to an anechoic measurement as possible. This is treated separately from the basic room correction which is what these sorts of things normally do. Changing exactly how much the DEQX is controlling also greatly affects the results and I don't know of any of the "normal" correction programs doing that. An example of this would be that I limit the processing to 5k on my Dynaudios and having it correct up to 6k completely changes the character of the sound. The DEQX is normally used as a crossover in hifi systems as opposed to just for speaker/room correction so it also has a lot of features relating to that and has 6 outs (for tri-amp or bi-amp + stereo subs). The higher end models have 3 sets of spdif so you could hook up your own high end converters and still tri-amp your speakers. 

To me, it's the exact same as putting a camera in focus. When it's slightly off, everything sort of has a haze around it and is fuzzy. When it gets put perfectly in focus, everything becomes tight and clear. This is exactly what it sounds like. I find it very noticeable on things like string quartets. Interestingly, everything gets drier since you no longer have that wash of sound but rather very focused reverb. I think this is a good thing in that it translates better to mains systems.


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## wst3 (Jun 29, 2017)

I know very little about DEQX, but I have to say, that approach to taking a measurement of a loudspeaker strikes me as odd. TEF has been around for almost 40 years now, and is quite capable of making anechoic measurements in non-anechoic spaces. This also sounds a lot like what Fulcrum Acoustics is doing with their Temporal Equalization.

While I do not believe that an equalizer can correct physical problems in a listening space yet, it does appear that we are getting closer to that goal.


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## Gerhard Westphalen (Jun 29, 2017)

wst3 said:


> I know very little about DEQX, but I have to say, that approach to taking a measurement of a loudspeaker strikes me as odd. TEF has been around for almost 40 years now, and is quite capable of making anechoic measurements in non-anechoic spaces. This also sounds a lot like what Fulcrum Acoustics is doing with their Temporal Equalization.
> 
> While I do not believe that an equalizer can correct physical problems in a listening space yet, it does appear that we are getting closer to that goal.



Well it corrects the phase and stuff of the speaker basically above around 200Hz and then the room below that. Of course you can set the EQ to wherever you want or make the speaker correction go as low as you want.

You don't have to do the measurements outside. It just gives you a larger time window before the first reflections. It strongly recommends doing it for bi- and tri- amp systems so that it can get an accurate measurement of exactly what's going on in the speaker in order to have the best crossover possible. In those cases they also recommend using an Earthworks mic instead of the usual cheap ones. For a full range (not necessarily full range speaker but just using a single full range output) speaker like my Dynaudios it's fine to do it in the room. For subwoofers it says to just do in the room as well.


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