New DEQX HDP-3 Express
- Thread starter Nyal Mellor
- Start date
The early DEQX processors were designated the PDC-2.6 (no preamp or analog remote control functionality) and PDC-2.6P (the preamp version with analog remote control). The remote control adds arm chair control of the unit and additional EQ functionality not available with the non-preamp version.
A modification program by DEQX some four years ago improved the power supply and upgraded the analog portion of the PDC-2.6 versions so that they were equivalent to the current HD model processors at that time.
A modification program by DEQX some four years ago improved the power supply and upgraded the analog portion of the PDC-2.6 versions so that they were equivalent to the current HD model processors at that time.
I have opened my PDC-2.6P yesterday and I do know why but there are no PGA3220/CS3110 chips which are responsible for analog volume control. There is space to solder them but there are none. I just wonder if it is that easy just to buy 3 chips and solder them in? This unit has the newest board rev. 6. The same as HD version. I also wonder what upgrades I can perform (to capacitors, op-amps, power supply etc) Any ideas?
Are they surface mount? If so, it will be non-trivial to solder them. Even if you put them in it is possible the firmware will not try to talk to it.
Actually it is easy to mount them on the board. The chips need to be in SOIC-16 case. Every service will do it for me. What is more I pretty sure that the firmware and software is exactly the same for all DEQX units based on rev. 6 board. And since it is 2.6p model it shall work. However I am not sure about a necessity for extra programming of these chips. I can send you photos of both boards with and without extra analog volume control.
I have already asked Alan form DEQX about a possibility to get analog volume control for my unit but I got a reply to let it go and upgrade to the newest model. Not excatly the answer I have been expecting since I spent so much so far.
I have already asked Alan form DEQX about a possibility to get analog volume control for my unit but I got a reply to let it go and upgrade to the newest model. Not excatly the answer I have been expecting since I spent so much so far.
On first photo you can see my 2.6P unit without PGA3220 chips mounted. Red circle is showing where I should mount them. On second photo there is the latest 2.6P HD model with caps, op=amps, power supply etc upgrades. Both have the same rev. 6 board.
Steve from Empirical Audio wrote somewhere that HDP-3 is simply 2.6p HD in bigger chassis with possibility to have both balanced and digital out board. Ach, and there is linear power supply which was too big for smaller 2.6 chassis. Probably that is the reason why they did not do it during HD upgrade.
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As I feared, they are surface mount. Fortunately the pin pitch is not very high so it is possible to solder them in but you still need fair amount of skill. Have you soldered parts before?
Searching for the part, I think these are the ones: http://www.digikey.com/product-sear...tation-op-amps-buffer-amps/2556125?k=PGA 3220
They have an extra digit in the part number though (look at the last four). So you need to identify the correct one. Fortunately the cost is pretty low at $1.50 each.
Here is the other problem. Without the volume control there has to be a bypass some place on the board. If you don't remove it, you will just be shorting out the output of these programmable gain parts. You need to look up the pin out of the chips above, find the output and then trace it to see if you can find it. If they use multi-layer PCB, that may be very hard to do. Once there, if you damage the PCB while you attempt to remove the bypass, then you are on a one-way road to make this work. And should you fail, you will have a pretty door stop
.
Looking at the picture, I see a few jumpers that are proud of the PCB that appear to have traces leading to and from the gain ICs. They may be it. Are they removable or are soldered?
Searching for the part, I think these are the ones: http://www.digikey.com/product-sear...tation-op-amps-buffer-amps/2556125?k=PGA 3220
They have an extra digit in the part number though (look at the last four). So you need to identify the correct one. Fortunately the cost is pretty low at $1.50 each.
Here is the other problem. Without the volume control there has to be a bypass some place on the board. If you don't remove it, you will just be shorting out the output of these programmable gain parts. You need to look up the pin out of the chips above, find the output and then trace it to see if you can find it. If they use multi-layer PCB, that may be very hard to do. Once there, if you damage the PCB while you attempt to remove the bypass, then you are on a one-way road to make this work. And should you fail, you will have a pretty door stop
.Looking at the picture, I see a few jumpers that are proud of the PCB that appear to have traces leading to and from the gain ICs. They may be it. Are they removable or are soldered?
If you mean 6 jumpers responsible for channel gain they are removable. Regarding bypass and other problems I may encounter it is here where I need a help of a professionalist No, I have not soldered that small parts before nor I am willing to. I will ask somebody else with better skills. But you are right I have to be sure what I am doing hence my questions.
Ok. I am going to get some sleep. It is 4 am here in Poland. I will post later.
No, I have not soldered that small parts before nor I am willing to. I will ask somebody else with better skills. But you are right I have to be sure what I am doing hence my questions.Ok. I am going to get some sleep. It is 4 am here in Poland. I will post later.
If you mean 6 jumpers responsible for channel gain they are removable. Regarding bypass and other problems I may encounter it is here where I need a help of a professionalist
Ok. I am going to get some sleep. It is 4 am here in Poland. I will post later.
Maybe Alan did give an answer you weren't happy with, so I'd push it if I were you and were determined to make this mod. Personally I'd ask directly for a quote from deqx to do the mod. Sure, a bit of shipping and time spent to get them to do it, but unless it were someone like Emprical Audio-who have the experience...tho I am quite certain HE would not do it now-I'd be very worried about getting someone else to do it, esp if it will be the first and only time they have touched the unit.
Would they guarantee it working after they touched it and supply a replacement if not? No, I didn't think so either.
If deqx tell you it cannot be done (which for all I know might be behind the answer Alan gave you) then unless you think it is only a ploy to get you to upgrade then it would seem pretty conclusive to me.
I simply suspect that asking forum boards this question might not be the safest route..
Hi Amir,
I am going to open the unit again tomorror or a day after tomorrow. I will also take some more detailed photos and check the specs. Then I will post again. Thank you for your support. Regarding volume control I have already bought MSB MVC-1 8 channel volume control with remote control so it is ok for my purpose but I still want to solve the puzzle why there is no analog volume control in 2.6p model and how I can install it alltogather with other upgrades
I am going to open the unit again tomorror or a day after tomorrow. I will also take some more detailed photos and check the specs. Then I will post again. Thank you for your support. Regarding volume control I have already bought MSB MVC-1 8 channel volume control with remote control so it is ok for my purpose but I still want to solve the puzzle why there is no analog volume control in 2.6p model and how I can install it alltogather with other upgrades
Hi dziemian, have you used the MSB MVC yet and what are your thoughts on its sound? Thanks Richard
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Yes, I have it but I use it now for 2 channel only. To be honest I liked the passive control better. I am going to change the system for bi-amping in few weeks. Then I will take advantage of its multichannel control. Actually if there was an analog volume control in my unit I would not buy it. If you have a possibility try multichannel passive units first.
very happy with my DEQX HDP3
Having owned my HDP3 for 2 years I'm very happy with it.
I've also had great after sales support from Deqx and Alan in particular - for a sales guy Alan knows the technical intricacies of the box like the engineers who designed it.
The flexibility it offers is also its challenge - it's not trivial to get it setup to get the most out of your system, and I'm still learning how to drive all the features.
I originally set it up as just a 3 way triamp crossover. It took me some time to get to the point of setting up my 2 ways outside to do a semi-anechoic measurement, but having done the measurements once, you can play around with the speaker correction at leisure.
I'm not correcting the sub woofer responses as they crossover at 80Hz, so even measuring outside the windowing required would not provide any resolution.
One great feature I discovered when doing the speaker measurement was that the DEQX determined my tweeter amp was out of phase with the midrange amp, and asked if I wanted it automatically corrected.
I have done a small amount of room correction, but I typically move around the room a lot and find my treatment works better.
I have mucked around with the parametrics to dial in room curves etc which is easy.
There are subtle features that you don't find in the instructions, such as how to set the gain on the analog outputs to the power amps to get the right balance at the listening position - I've found it a great help to have other owners provide advice via forums.
You have the option of traditional IIR (Linkwitz-Riley or Butterworth) or Linear Phase crossovers up to 300dB/octave.
The speaker correction adjusts amplitude and phase response and time-aligns the speaker. Time alignment can also be done between a speaker and a sub to the listening position.
It won't allow you to set crossover slopes that are too steep based on a maximum delay threshold - given I only use it for audio (not movies), I'd prefer it to delay the other channels and let me run as steep a crossover as I want - I probably can, just haven't found that setting.
I run a music laptop via USB to an external USB/SPDIF converter to the XLR AES input on the DEQX, which allows me to keep my CD player as a backup and connect via SPDIF COAX.
The sound is fantastic.
If you're not a tinkerer, then if you go down the DEQX path I strongly recommend getting it professionaly installed. If you are a tinkerer, then still consider professional installation as a baseline and tinker from there (you would learn a massive amount about driving it while it was being installed also).
It's in a different league to the Behringer DCX 24/96 - I can't compare to the other room correction devices mentioned in this thread - I use it for the crossover and speaker correction - in that department I don't know of another product that comes close.
cheers
Mike
Having owned my HDP3 for 2 years I'm very happy with it.
I've also had great after sales support from Deqx and Alan in particular - for a sales guy Alan knows the technical intricacies of the box like the engineers who designed it.
The flexibility it offers is also its challenge - it's not trivial to get it setup to get the most out of your system, and I'm still learning how to drive all the features.
I originally set it up as just a 3 way triamp crossover. It took me some time to get to the point of setting up my 2 ways outside to do a semi-anechoic measurement, but having done the measurements once, you can play around with the speaker correction at leisure.
I'm not correcting the sub woofer responses as they crossover at 80Hz, so even measuring outside the windowing required would not provide any resolution.
One great feature I discovered when doing the speaker measurement was that the DEQX determined my tweeter amp was out of phase with the midrange amp, and asked if I wanted it automatically corrected.
I have done a small amount of room correction, but I typically move around the room a lot and find my treatment works better.
I have mucked around with the parametrics to dial in room curves etc which is easy.
There are subtle features that you don't find in the instructions, such as how to set the gain on the analog outputs to the power amps to get the right balance at the listening position - I've found it a great help to have other owners provide advice via forums.
You have the option of traditional IIR (Linkwitz-Riley or Butterworth) or Linear Phase crossovers up to 300dB/octave.
The speaker correction adjusts amplitude and phase response and time-aligns the speaker. Time alignment can also be done between a speaker and a sub to the listening position.
It won't allow you to set crossover slopes that are too steep based on a maximum delay threshold - given I only use it for audio (not movies), I'd prefer it to delay the other channels and let me run as steep a crossover as I want - I probably can, just haven't found that setting.
I run a music laptop via USB to an external USB/SPDIF converter to the XLR AES input on the DEQX, which allows me to keep my CD player as a backup and connect via SPDIF COAX.
The sound is fantastic.
If you're not a tinkerer, then if you go down the DEQX path I strongly recommend getting it professionaly installed. If you are a tinkerer, then still consider professional installation as a baseline and tinker from there (you would learn a massive amount about driving it while it was being installed also).
It's in a different league to the Behringer DCX 24/96 - I can't compare to the other room correction devices mentioned in this thread - I use it for the crossover and speaker correction - in that department I don't know of another product that comes close.
cheers
Mike
deqx mixed bag...
hey guys, i own the express too. works well for me even though i find the process confusing here and there. harware has been a major problem for deqx. the xpress uses dac coupling caps that hipass aroundv30 hz. i replaced mine w bigger film caps. now it measures flat from mic pre in to its out.
worse, my 2 buddies deqx devices went bad. one is a 2.6 which stopped working altogether two times ( after deqx xformer mods and gain mod). other buddys early deqx totally fried his expensive carver ribbons. i suspect again te
he output caps shorting out but whokows. i woulnt use deqx output w/o a larce coupling cap to a tweeter, to say the least.
so, a mixed bag in my experience...
justus
hey guys, i own the express too. works well for me even though i find the process confusing here and there. harware has been a major problem for deqx. the xpress uses dac coupling caps that hipass aroundv30 hz. i replaced mine w bigger film caps. now it measures flat from mic pre in to its out.
worse, my 2 buddies deqx devices went bad. one is a 2.6 which stopped working altogether two times ( after deqx xformer mods and gain mod). other buddys early deqx totally fried his expensive carver ribbons. i suspect again te
he output caps shorting out but whokows. i woulnt use deqx output w/o a larce coupling cap to a tweeter, to say the least.
so, a mixed bag in my experience...
justus
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