Ryssen said:
I don't know. The DEQ v2 was not mine. Just one to upgrade and it left.
In fact, I don't realy know what is this component. I took a picture.
It can be read: F D65AB and 11120 05/06.
An externally hosted image should be here but it was not working when we last tested it.
Seems to be from Fairchild.
Concerning the 3.3v, I also discovered that inside the DEQ v1, Behringer mixed analog and digital 3.3v. They produce analog 3.3v with the same 3.3v and just insert a coil just before the chip pin... As in the DCX in fact.
Have a nice digital low noise psu is important in fact.
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Ok,but in DEQv1 (the one I have)maybe the LM317 could be substituted with a LT1763 2,5v on one of your miniregPCB`s?
Ryssen said:
We need to look what is powered first with 2.5v. In theory, you can remove the 2 resistors and fit a fixed reg in place. But good luke with the legs. 😉
Let me finish do draw the dsp board psu. I'll post it tomorow.
Stef...
DEQ2496 v1 DSP PSU schematics
http://www.awdiy.com/index.php?page=references
Look what they have done with ground and to produce the analog 3.3v...
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http://www.awdiy.com/index.php?page=references
Look what they have done with ground and to produce the analog 3.3v...
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stef1777 said:
Stephane,
Good job! Isn't this the same supply that is used in the DCX2496?
Jan Didden
janneman said:
No exactly the same. If I understand the DCX schematics, they produce the +3.3vA with the +5vD using a transistor. On the DEQv1, they directly use the 3.3vD with a coil to ovoid high frequency go back.
The big difference between the DCXv1 and the DEQv1 is ground plane. Only one mixed for the DEQ (AGND and DGND pins from AKM chips directly connected to the same ground). One analog and one digital for the DCX. DEQv2 DSP seems completely redesigned on this.
This may be explain why with the best possible psu, we still have a low level ground noise.
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stef1777 said:
Stef, with that knowledge wouldn't be the best to redesign your board and include all those voltages, including 9V regulated, or make separate board that will solve these issues. After that we just have to look where to cut the traces and completely abandon Behringer PS mess. It seems like that there is no other option. That way we could have one universal power supply for DCX and DEQ, that could incorporate your nice regulators. I have schematics for DCX that shows DSP power supply regulators (not switching supply) and will be happy to send them to you if you need.
Re: Deq2496 direct out mod
That looks very interesting, i was looking for information to upgrade the opamps and caps, but i like to try this mod first. unfortunately I'm a newbie to dacs so i can use a little help 🙂
I can't see on the photo how the caps are wired up, could someone please explain that to me?
Photo
sendler said:
That looks very interesting, i was looking for information to upgrade the opamps and caps, but i like to try this mod first. unfortunately I'm a newbie to dacs so i can use a little help 🙂
I can't see on the photo how the caps are wired up, could someone please explain that to me?
Photo
Re: Re: Deq2496 direct out mod
You'll find the pinout on this page: http://www.awdiy.com/index.php?page=references
If you wait a little, I'm working on a board to output the ADC and DAC signals without the need to cut something on the flat cable.
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badduh said:
You'll find the pinout on this page: http://www.awdiy.com/index.php?page=references
If you wait a little, I'm working on a board to output the ADC and DAC signals without the need to cut something on the flat cable.
.
Thank you very much.
i read on your site that the caps are .47uf each. so am i correct that you put 5 caps parallel with each other so you get a total amount of 5x0.47=2.35uf, and you put this stack between the new wires from aoutl+ and aoutr+? to pin 2 of the xlr chassis or in my case a new rca chassis.
Wat is the advantage of using a stack of caps instead of lets say one with a value of 2.2 uf?
Unfortunately here in Holland i can't get the Dayton caps, what i can get is the following:
-AUDYN-CAP plus foil capacitor 2.20uF 800V 25 x 43mm, costing $12 each, a would like toe use one a side in stead of 5x0.47 as that costs 5x$7,5= $37,5 a side, this should be a very good sounding cap.
-AUDYN-CAP KP-QS foil capacitor 0.47uF 400V 11 x 19mm, costing $1.90 each so it would cost me 5x$1.9=$9,50 a side, what seems reasonable toe me, of course a could also use one of 2,2 uf costing $3,00 each, this is a normal sounding cap, not bad but nothing special either.
-Black gate 50 volt Nx-Hi-Q 0,47 uf, costing 3 euro each so 5x$3=$15,00 a side, what is the maximum a would like to spend. the 2,2 uf is not available.
Which cap would you recommend?
i read on your site that the caps are .47uf each. so am i correct that you put 5 caps parallel with each other so you get a total amount of 5x0.47=2.35uf, and you put this stack between the new wires from aoutl+ and aoutr+? to pin 2 of the xlr chassis or in my case a new rca chassis.
Wat is the advantage of using a stack of caps instead of lets say one with a value of 2.2 uf?
Unfortunately here in Holland i can't get the Dayton caps, what i can get is the following:
-AUDYN-CAP plus foil capacitor 2.20uF 800V 25 x 43mm, costing $12 each, a would like toe use one a side in stead of 5x0.47 as that costs 5x$7,5= $37,5 a side, this should be a very good sounding cap.
-AUDYN-CAP KP-QS foil capacitor 0.47uF 400V 11 x 19mm, costing $1.90 each so it would cost me 5x$1.9=$9,50 a side, what seems reasonable toe me, of course a could also use one of 2,2 uf costing $3,00 each, this is a normal sounding cap, not bad but nothing special either.
-Black gate 50 volt Nx-Hi-Q 0,47 uf, costing 3 euro each so 5x$3=$15,00 a side, what is the maximum a would like to spend. the 2,2 uf is not available.
Which cap would you recommend?
An other question comes on my mind.
Do i really have to cut the output wires from the dac to the output stage so that the original output stage doesnt have any influence on the direct output stage, or can i just leave everything as it is and put the wires to the coupling caps on the back of the x1 connector?
Do i really have to cut the output wires from the dac to the output stage so that the original output stage doesnt have any influence on the direct output stage, or can i just leave everything as it is and put the wires to the coupling caps on the back of the x1 connector?
I wish there is a more clear thread detailing each mod.
I just did a simple mod and find it very effective in improving bass (no, I don't mean pushing up eq of the lower fz)
If you study the ak4393 dac datasheet, look at the analog 5V decoupling for the Vref and Avdd pins, it requires separate 0.1uf and 10uf for each of those pins. Guess what, the deq only has only one 0.1uf for both pins, those pins are starving for quality power.
Obviously the best solution is to give it a separate clean PS, but I lack time and too lazy. I did the next next best thing, I put a Oscon SEP 470uf directly on the Vref & Avdd pins.
Nice improvement on the bass, but I am using direct transformer out, so YMMV.
Anyways, the deq is poorly decoupled and adding good caps in other place will likely improve things too.
Check the pic.
I just did a simple mod and find it very effective in improving bass (no, I don't mean pushing up eq of the lower fz)
If you study the ak4393 dac datasheet, look at the analog 5V decoupling for the Vref and Avdd pins, it requires separate 0.1uf and 10uf for each of those pins. Guess what, the deq only has only one 0.1uf for both pins, those pins are starving for quality power.
Obviously the best solution is to give it a separate clean PS, but I lack time and too lazy. I did the next next best thing, I put a Oscon SEP 470uf directly on the Vref & Avdd pins.
Nice improvement on the bass, but I am using direct transformer out, so YMMV.
Anyways, the deq is poorly decoupled and adding good caps in other place will likely improve things too.
Check the pic.
Attachments
badduh said:
why not just use one single 4.7uf cap?
I recommend the Vishay/ERO MKT1822, they are one of the best caps I have tried and cheap too. You can get it from Farnell.
I changed opamps on the AUX out from JCR4580 to LM4562 yesterday.
I think it was a downgrade
smaler sound stage life less etc.
So now I am locking for 3 JCR4580 to change back to.🙄
please,they seems to be hard to find.
Thinking on the shipping etc.
I think it was a downgrade
smaler sound stage life less etc.So now I am locking for 3 JCR4580 to change back to.🙄
please,they seems to be hard to find.
Thinking on the shipping etc.