DEQX vs Twindac+/Django (Off Topic)

by dr.cube @, Friday, September 22, 2006, 11:46 (4139 days ago)

Hi All,

I read that some of you use the the DEQX speaker correction device.
As I understand it that device includes a DAC (well, six of them) and an analogue volume control (resistor ladder). So you don't need an additional dac like the Twindac. You also don't need an additional volume control like the django. I'm currently thinking about getting the twindac and the django, but I've never heard those. Neither do I know the DEQX. The DEQX could replace those two and even the passive speaker crossovers needed for the Orphean.

So has anybody of you actually directly compared these two approaches?
Anyobody out there who owns both the DEQX and the tinwdac/django?
Price would amount to roughly the same for both combinations.
So if anybody can comment on the sonic differences, please do so.
I do own already the Orphean Ultra DIY, so I think that additional digital time correction should not be needed anymore with this speaker system.
I use my own DIY 2A3 amp for the orpheans.

Thanks

Wolfgang

Tags:
0

DEQX vs Twindac+/Django

by giulio @, Friday, September 22, 2006, 12:12 (4139 days ago) @ dr.cube

Hi
The DEQ2496 is just a digital equalizer and has only two channels.

The DCX2496 is a digital crossover and has six dacs. The dacs are oversampling and the twindac is not. The output stage is ghastly but you can bypass it and have passive output as the twindac. Neither the DEQ or DCX come with a volume control. So for the DCX you need to build a six channel volume control. I have the DCX and two pairs of TX102 transformers (same as in the Django). I am planning to use the TX102 to control volume on mid and high and a buffered stepped attenuator for bass. The DCX can do crossover, control phase (better said delay) and do some equalization.

I will report back. I think the outcome would be quite good but I would not be surprised if a single buffer before three amps with passive line level crossover sounded better. Less is more...

Giulio

Tags:
0

DEQX vs Twindac+/Django

by Flecko @, Friday, September 22, 2006, 13:42 (4139 days ago) @ giulio
edited by unknown, Friday, September 22, 2006, 14:24

Hi Giulio,
I think you mixed something up. The DEQ2496 is a product of Behringer, Wolfgang means the DEQX P2.6P.

Hi Wolfgang,
At first: I didn't have heard any of those :smile: I like the idea of the DEQX very much, I think this is technical the right way... BUT on the other hand, you need six amplifers of good quality and a messurement system to do the right "corrections" to the sound. It will be very expensive. And second the twindac has battery power. I have made test with my own DAC, used it with and without batteries. I think it is a "must have" to achieve highend sound...so I would take the Twindac and a passive crossover for the first. If you still like to improve your sound you could get an active crossover, a lot of amps and a messurementsystem, then you have at least a good source.

Greetings Adrian

Tags:
0

DEQX vs Twindac+/Django

by giulio @, Friday, September 22, 2006, 15:31 (4139 days ago) @ Flecko

Hi Adrian,

sorry. I completely mixed it up. They all have similar names...

Yet, the DEQX does basically the same stuff as the Behringer DCX at 15 times the price. I can have tranformer volume control on the bass channel too and still have quite some cash to spare.

If we are all agreeing with Bert's philosophy (and I tend to) we want to bypass the analogue output stage of either of the two anyway.

The broad answer is still the same. I will try and report. I have a hunch that I might want to use it just for the bass channel with passive line level xover on the other two.

Incidentally, I already have a DSP8024 (the older and obsolete brother of the DEQ8024) which I think is quite good to equalize low freq room modes.

best
g

Tags:
0

Avatar

DEQX vs Twindac+/Django

by PeterSt. ⌂ @, Netherlands, Saturday, September 23, 2006, 07:20 (4138 days ago) @ dr.cube

Hi Wolfgang,

My personal opinion would be that you seem to want the DEQX for the wrong reasons. IOW, If I'd buy this device, I would go for the 6 digital-out option ... (instead of the analogue outs).

It also contains digital volume control, and *that* might be what you want.
Note that this "psychologically" is okay, once you start tweaking the digital domain anyway (what this device is for). With the digital volume control you can avoid all pre-amps (active and passive).

Today (or maybe the whole weekend) I will try once more with the digital volume control as I can do it with my setup (via the Fireface800 soundcard), and try to sense what's better : loosing micro detail because of my (active) pre-amp, or having micro detail without it, but loosing whatever it exactly is by molesting the digital source (compressing digital is different from "compressing" analogue).

The same might account for a device like the DEQX : what you gain by super time-alignment, might be lost on dynamics. Difficult, difficult ...

Btw, I had the Behringer representative (digital version, incl. dig-out, still using my own DAC), but the sound went completely flat.

Lastly, with Bert's speakers, maybe you shouldn't even try to improve the timing ... (which is not what you are after anyway, I think).
:bey:
Peter

Tags:
0

Avatar

DEQX vs Twindac+/Django

by PeterSt. ⌂ @, Netherlands, Saturday, September 23, 2006, 11:58 (4138 days ago) @ PeterSt.
edited by unknown, Saturday, September 23, 2006, 12:13

Okay, I did some tests ... (behind the computer screen :read: ) ...

This is just stupid theory, and without adjustments (see later) never touch the volume of the digital domain. :stop:

Our source is a 44.1KHz 16 bit CD WAV file.

[image]

Here's the original (for the screen) uncompressed wave, just for reference. It's at the same time offset as the other one.

[image]

This is 0.8ms of it (left channel only), and the image is vertically compressed (on the screen only) in order to let this part of the "wave" show properly.
You can see the general (lower frequencey) wave as a sinus, the "micro data" modulated on top of that.

Now remember, this is digital.
All the data is contained in 16 bit samples, meaning that 65,536 values are available to represent one sample. One sample is shown as one sideways step in the above. The height represents the amplitude, or volume. The frequency emerges from the amplitue versus time, or IOW the sideways relative changes (look at the general big wave, which is a lower frequency tone).

Somewhere in the file will be the maximum value of 65,536 at the top of the wave or at the bottom of the wave (assuming that 100% of the "headroom" is used). For geeks : actually it will be half of the 65,536, the middle of that meaning 0 (Volts). Never mind that.

From this follows, that additional gain (in the digital domain) is not allowed, or else the wave is "clipped" (the wave wants to exceed the 65,536, but there's no storage space for that, so the wave "squars off" at the top (+ Volt) or bottom (- Volt)).

So whatever we want to do when the digital domain is to be manipulated, it can only be done by means of lowering volumes. *If* there needs to be gain, first the overall volume level has to be lowered, in order to create headroom for the gain. This already implies that gain should be avoided (see later). Also note, that bass management stuff (like LF (low frequency) boost) *will* lower the general volume first, in order to gain the bass frequencies.

Now, when the volume is digitally controlled, about 1 bit of "resolution" will be lost per 6dB of attenuation. Look at the picture again ...
E.g. the first part of the wave going downwards, has at it's bottom the smallest step possible (it goes one "value" upwards again); when the volume is lowered, this step will be compressed away, and the difference in amplitude will be levelled to "no change". So by lowering the volume, the resolution will be less.

In my case, playing at a for me normal level, I have an attenuation of 24dB, meaning that I loose 24/6 = 4 bits of resolution. Theoretically this implies that for the 16 original bits, I loose 25% of the resolution as present in the original.

Bad. :evil:

All is solved when we first create headroom for our manipulative stuff, which can be done by highering the number of bits per sample. For example, if we have 24 bits per sample, very theoretically we still loose 1 bit per 6dB, but at an attenuation of 24dB there are 18 bits left (24 - 6), which is still more than the original.

Knowing this theory before, it is that what I just tested;
Thus, I loaded a 16 bit WAV file, converted it to 24 bits, lowered the volume by 24dB, saved the file, reloaded the file, applied a gain of 24dB ... and the result was the same as the orginal 16 bit file.
Note that this proves no data (or details in music) are lost by this way of working;
Applying the same without converting to 24 bits, does change the data drastically.

Where this sufficiently works with 24dB attenuation, with more attenuation it might not, or *will* not. In the end you will have compressed all to a near flat line.
Also note that there are official means to convert to 32 bits, giving more headroom for attenuation (hence playing less loud without molesting the sound).

Where this thread of course is about the DEQX, be warned :
When 16 bit material is digitally fed to this processor, it will process all with 16 bits internally. You know now this is wrong ...
It does 24 bit processing, but only when it's fed with 24 bit material.
Also when it's fed with an analogue signal, it will process with 24 bits.


The conclusion I have for myself, is that my XXHighEnd player must convert the data to 24 bits (or more) before handing it over to the soundcard. Only then I can be psychologically happy in controlling the volume in the digital domain. :prankster:

Peter

Tags:
0

DEQX vs Twindac+/Django

by giulio @, Saturday, September 23, 2006, 12:52 (4138 days ago) @ PeterSt.

Hi Peter,

Btw, I had the Behringer representative (digital version, incl. dig-out,
still using my own DAC), but the sound went completely flat.

Did you feed the Behringer a digital signal or an analog one? In the latter case what voltage were you feeding?

Thank
Giulio

Tags:
0

Avatar

DEQX vs Twindac+/Django

by PeterSt. ⌂ @, Netherlands, Saturday, September 23, 2006, 13:16 (4138 days ago) @ giulio

Hi Peter,

Btw, I had the Behringer representative (digital version, incl.

dig-out,

still using my own DAC), but the sound went completely flat.


Did you feed the Behringer a digital signal or an analog one? In the
latter case what voltage were you feeding?

Thank
Giulio

Hi Giulio,

That was digital-in and digital-out.
Note though, it was the parametric equalizer (and feedback destroyer), but the principles are the same; without changeing anything (so no frequencies changed) the sound was already flat. But *also* note there was already a standard -9 dB or so attenuation applied, in order to have headroom for allowed gain, whether I used that or not.

The analogue version of the Behringer worked better for retaining the sound (details), but it is noisy (not audible, but by measuring) and had a 20ms (processing) delay.

Regards,
Peter

Tags:
0

DEQX vs Twindac+/Django

by soundcheck @, Germany, Saturday, September 23, 2006, 17:20 (4138 days ago) @ PeterSt.

Hi folks.

I am a bit confused. Are you talking about Behringer DEQ-Equalizer or DCX-crossover.

Anyhow. As a matter of fact the Behinger DCX2496 is phantastic value for the
money equipment at 230€. With a bit of tweaking you end up at 300€.
That's more than fair. You can find all kind of stuff describing these tweaks in the net.

Running the DCX analog-in with consumer level signal is a noisy adventure.
Here you have to change the input section. If you run it on differential
Pro-Levels it plays acceptable. You could skip almost the whole output stage and this would perfectly match consumer level gear
Most of the "HiFi"-users are running it on low levels, which of course will not bring best results, especially in the area of dynamics. It needs some tweaking.

@Peter:
I think you pointed out - more than clear - what happens to the digital signal if you loose some bits. That's the same with the DCX. If you running the DCX with low consumer levels you loose quite some bits and dynamics.

BTW: For me, the DCX2496, is the perfect piece of EQ to integrate my subwoofers, timewise and
responsewise into the system and room. There is a huge
difference if you are able to work with 48/db filter slopes and parametric equalizers in the lower range, compared to passive approaches.
Though - It wouldn't fit my minimalistic approach in the upper range, which I am running more or less filter-free.
Of course a DECX would be a much better choice with its phase linear filters than the DCX2496.
For my subwoofers I'd regard it as overkill.
One more comment: I never ever had a better time alligned system when it was automatically
alligned by the DCX. Though I regarded this as lower priority compared to the overall sound quality.

Looking at a 4000$US pricetag for the DEXC , that's what is keeping my hands off. But in general I'd love to give it a try. :grin:

I am actually waiting for somebody who'll develop some kind of PC based solution. Peter: Wouldn't that be something for the future roadmap of GC.:smile:

Klaus

Tags:
0

Avatar

DEQX vs Twindac+/Django

by PeterSt. ⌂ @, Netherlands, Saturday, September 23, 2006, 18:36 (4138 days ago) @ soundcheck
edited by unknown, Saturday, September 23, 2006, 18:40

Hi folks.

I am a bit confused. Are you talking about Behringer DEQ-Equalizer or
DCX-crossover.

Hi Klaus,

Assumed this is addressed to me ... my fault. I was confusing by "generalizing" different products, though knowing how they all work.
Anyway, I had this one : http://www.behringer.com/DEQ2496/index.cfm?lang=ENG before I brought it back. Note that this is not just an equalizer, but a 10 band parametric equalizer (amongst more).

In combination with Room EQ Wizard you'd have auto-calibration for room correction (with something like a Behringer EMC 8000 measuring microphone).

I am actually waiting for somebody who'll develop some kind of PC based
solution. Peter: Wouldn't that be something for the future roadmap of
GC.:smile:

Well, at one time I had all software collected to start doing this, with the PC as origin. When I was done with this, I though : wait a minute, then I *have* to use the PC from now on. And then I dropped it.
Also note that Vista contains excessive (auto calibration) stuff in this direction.

In the end I don't think I use something else than the PC, but it takes a lot more than audio to state that (video being the only thing else, but *also* complicated).

Peter

Tags:
0

DEQX vs Twindac+/Django

by giulio @, Sunday, September 24, 2006, 08:13 (4137 days ago) @ PeterSt.

Hi Peter,

That was digital-in and digital-out.
Note though, it was the parametric equalizer (and feedback destroyer), but
the principles are the same; without changeing anything (so no frequencies
changed) the sound was already flat. But *also* note there was already a
standard -9 dB or so attenuation applied, in order to have headroom for
allowed gain, whether I used that or not.

The analogue version of the Behringer worked better for retaining the
sound (details), but it is noisy (not audible, but by measuring) and had a
20ms (processing) delay.

Interesting. Where you feeding a 16bit signal to the DEQ?
I think it upsamples everything to 24bit. So -9db should be 22 bit at worst. If it does not upsample you were hearing 14bits which would easily explain the flatness. If it does upsample and you prefer the analogue version, the upsampling algorithm or jitter seem the likely culprits rather than the digital processing part.

Best
Giulio

Tags:
0

DEQX vs Twindac+/Django

by Henry Venema @, Saturday, September 23, 2006, 17:28 (4138 days ago) @ dr.cube

While I have no direct experience comparing the DEQX with the Twindac, I do have the DEQX in my system (I have also heard the Twindac and love it. Had I not purchased the DEQX I would have bought the Twindac).

The DAC by itself is quite good, but once I implemented the digital correction filters my speakers took a major jump forward in performance. My AER MD3 drivers never sounded as good: soundstage depth and width increased, voices sounded more natural, overall tone improved significantly. The in-room EQ option is also quite helpful, particularly if you have a poor sounding listening room or a non-symmetrical room.

I've owned many different digital front ends, and I can say without hesitation that the DEQX is the best setup that I have owned to date.

HOWEVER, be aware that using the software to set the system up can be difficult and I found the learning curve quite steep. There are literally thousands of options and possible configurations, many of which require more knowledge about speaker crossovers and design than I have. But if you're patient, and simply use the default software settings and have a good ear you can make your way through all the options and find a configuration that works for your system. I have mine set up with three different profile configurations, which lets me instantly compare different crossover slopes or filter configurations. I select the configuration that sounds best, then set up new configurations that are variations of the best sounding one and from there repeat the process. Every parameter can be varied. So I think I have years of fun ahead of me, but for some that might sound like years of an endless nightmare.

Now if they could make an audiophile version of the DEQX the performance would take a whole other leap forward. I think the pre-amp section could use some work, but I will have to save that for another day, probably sometime after the warrantee has ended, and hopefully by then there will be some good mods available from people who have more expertise and skill than I do.
Henry

Tags:
0

DEQX vs Twindac+/Django

by soundcheck @, Germany, Saturday, September 23, 2006, 20:08 (4138 days ago) @ Henry Venema

Now if they could make an audiophile version of the DEQX the performance
would take a whole other leap forward. I think the pre-amp section could
use some work, but I will have to save that for another day, probably
sometime after the warrantee has ended, and hopefully by then there will
be some good mods available from people who have more expertise and skill
than I do.

Henry.

Interesting post. That's what I guessed. You got a lot of options with the DECX.
You'll get a perfectly integrated and time alligned, phase linear system, which probably none of the people here has ever heard. And beside that you'll get an absolute flat response throughout the spectrum, which none of us ever heard either. I'd say that's just great.

Tja - And still there are some tiny "deficiencies".

Usually you don't get it all in one box, unless you do it by yourself.
Unfortunately you can't develop such a box by yourself. So you have to live with certain compromises.

I'd say - Enjoy your system.

Tags:
0

DEQX vs Twindac+/Django

by robmatthew @, Tuesday, September 26, 2006, 15:56 (4135 days ago) @ Henry Venema

Hi Henry,

I found that putting the new Monarchy audio dac at the digital outputs of the DEQX for the mid range drivers made a substantial improvement over the built-in DEDQX DACS,

Tags:
0

Avatar

DEQX with Twindac+...

by Bert @, Tuesday, September 26, 2006, 16:35 (4135 days ago) @ robmatthew

Hi Rob,

I could not resist this one....

I found that putting the new Monarchy audio dac at the digital outputs of the DEQX for the mid range drivers made a substantial improvement over the built-in DEDQX DACS,

.... simply because I am 100% sure that this would improve the same or even better with the TwinDAC+

Ciao,

Bert

--
BD-Design - Only the Best!

Tags:
0

DEQX with Twindac+...

by Henry Venema @, Tuesday, September 26, 2006, 18:12 (4135 days ago) @ Bert

I never thought of using another DAC with the DEQX but that is an interesting option. As I mentioned in my previous post, I have not been able to compare the TwinDac with the DEQX. When Bert and I were at the AudioFest in Denver I thought the TwinDac sounded amazing with the Oris system. If was only going to use the DEQX as a DAC the TwinDac would be a better choice, However, what the DEQX gives over and above any DAC on the market is the flexibility to compare 4 different crossover profiles at a time as well as different crossover algorithms. The difference between using the DEQX only as a DAC and with the speaker correction algorithms is nothing short of astonishing, you won’t believe it how much better this sounds until you actually hear the difference.

So far I’ve tried at least 40 different crossover profiles. The DEQX can measure actual in room response at the precise point of my listening chair. Initially the in room EQ yielded significant improvements towards a flat frequency response; however after spending a lot of time building bass traps and acoustical panels for wall and ceiling in my listening room, the in room EQ was less dramatic.

The DEQX is an amazing product for a DIY’er like myself. Since it measures the frequency response of any speaker, and plots the frequency response before it calibrates a correction algorithm, tuning speakers for a flat frequency response is quite simple, particularly for adding the right amount of polyester fill. So rather than tuning my speakers to just fit my own room, the DEQX lets you map both the actual performance of the speaker and once the best results are achieved then room problems can be dealt with. In the past I was never sure if a perceived problem was the result of my listening room or a problem with my speakers.

Once I finally settle on an active crossover, I’ll build a passive crossover to hear what kind of sound quality can be achieved with a single amp instead of bi-amping. Right now I’m using a pair of Serious Stereo 2A3 mono blocks for the AER MD3 and a pair of NuForce Ref. 8 for the bass drivers, and if anyone ever manages to make their way to Brandon, Manitoba, Canada, stop by for some cold Canadian beer and great music.

Henry

Tags:
0

DEQX vs Twindac+/Django

by GC, Sunday, October 01, 2006, 09:26 (4130 days ago) @ Henry Venema

Hi Henry,

Now if they could make an audiophile version of the DEQX the performance
would take a whole other leap forward. I think the pre-amp section could
use some work, but I will have to save that for another day, probably
sometime after the warrantee has ended, and hopefully by then there will
be some good mods available from people who have more expertise and skill
than I do.
Henry

Empirical Audio (www.empiricalaudio.com) offers modding for the DEQX.
For only $3150.
They were happy with the digital side and focused on the analog section. They claim, their modded DEQX bettered a modded ML38 preamp.

Jens

Tags:
0

DEQX vs Twindac+/Django

by Henry Venema @, Tuesday, October 03, 2006, 16:53 (4128 days ago) @ GC

Jens
I've contacted Empirical Audio, and they tried to sell me an even more expensive upgrade between $5000-6000. Their web page indicates that all of the mods are done to the preamp section, but now they also have mods for the digital section including a USB input (which seems redundant since I have my computer connected by way of the Lynx AES16 soundcard to the DEQX with a cable specifically designed for this application). If most of the mods are for the preamp section that is the case then it probably would make more finacial sense to buy a DEQX withou the preamp and use a seperate stand alone preamp.

The DEQX company is apperantly not interested in developing an audiophile version of their units. They are selling so many of these things and making tons of cash that they don't see any need to change what their doing, and who can blame them. Having a steady stream of cash coming into an audio company is becoming more difficult these days. However, I think that someone could also make money selling a more reasonably priced upgrade for the DEQX, or a DIY package of parts and instructions. I guess we will have to wait, but given the popularity of these units I think that we will be seeing highend audiofile units from other audio companies that will out perform the DEQX in the very near future. If you snooze you loose. In the mean time I'm learning so much more about crossover design than I imagined.
Henry

Hi Henry,

Now if they could make an audiophile version of the DEQX the

performance

would take a whole other leap forward. I think the pre-amp section

could

use some work, but I will have to save that for another day, probably
sometime after the warrantee has ended, and hopefully by then there

will

be some good mods available from people who have more expertise and

skill

than I do.
Henry


Empirical Audio (www.empiricalaudio.com) offers modding for the DEQX.
For only $3150.
They were happy with the digital side and focused on the analog section.
They claim, their modded DEQX bettered a modded ML38 preamp.

Jens

Tags:
0

Avatar

DEQX

by PeterSt. ⌂ @, Netherlands, Wednesday, October 04, 2006, 10:45 (4127 days ago) @ Henry Venema

Hi Henry,

Assuming you don't yet : you really should try to go from the Lynx to the DEQX by analogue means ...
What I read, is that when the connection is digital and the DEQX is fed with 16 bits (which most probably will come out of the Lynx (??)), it will process the data with 16 bits too. Well, THAT's wrong ...
It will process with 24 bits when it's fed with an analogue signal ...

Peter

I've contacted Empirical Audio, and they tried to sell me an even more
expensive upgrade between $5000-6000. Their web page indicates that all
of the mods are done to the preamp section, but now they also have mods
for the digital section including a USB input (which seems redundant since
I have my computer connected by way of the Lynx AES16 soundcard to the DEQX
with a cable specifically designed for this application). If most of the
mods are for the preamp section that is the case then it probably would
make more finacial sense to buy a DEQX withou the preamp and use a
seperate stand alone preamp.

The DEQX company is apperantly not interested in developing an
audiophile version of their units. They are selling so many of these
things and making tons of cash that they don't see any need to change what
their doing, and who can blame them. Having a steady stream of cash coming
into an audio company is becoming more difficult these days. However, I
think that someone could also make money selling a more reasonably priced
upgrade for the DEQX, or a DIY package of parts and instructions. I guess
we will have to wait, but given the popularity of these units I think that
we will be seeing highend audiofile units from other audio companies that
will out perform the DEQX in the very near future. If you snooze you
loose. In the mean time I'm learning so much more about crossover design
than I imagined.
Henry

Tags:
0

DEQX

by Henry Venema @, Thursday, October 05, 2006, 21:29 (4126 days ago) @ PeterSt.

At the time of purchase I inquired with Lynx and Vincent of VRS Audio Sytems (they use the Lynx card in their servers). The Lynx AES16 is a digital only card with no analogue outputs, whereas their other cards have analogue and digital outputs. the AES16 has newer reclocking technology that the other cards don't have, and it is significantly superiour to their other cards, hence my purchase of the AES16
Henry

Tags:
0

DEQX

by Henry Venema @, Thursday, October 05, 2006, 21:36 (4126 days ago) @ PeterSt.

For anyone interested in finding out more about the Lynx AES16 check out this link
http://www.lynxstudio.com/aes16.html

Henry

Tags:
0

RSS Feed of thread