Best Op-amps for Behringer DCX2496?

[Spiritzly]

Does anyone have a few op-amp choices, cost no object, that would be the best in this unit?

Thanks!

 

[Spiritzly]

Anyone?????

 

[lucpes]

What opamps are currently used?

 

[mb]

I presume that the current opamps are smt NRC4580s. I really wouldn't suggest any fancy, superfast opamps (newer ADs, LM6172, etc) given the potential noise on the smps power supply and from the digital devices everywhere. I changed my opamps to opa2132. The desoldering is no fun.

 

[stef1777]

The opamp are JRC NJM4580.

http://www.njr.co.jp/pdf/ae/ae04056.pdf

Quand be replaced by AOP2604AU too.

 

[stef1777]

Sorry, I was thinking to the DEQ2496 nor the DCX.

JRC 4580 and AOP2604 are for the DEQ. I don't know for the DCX.

I'm looking for the Behringer DEQ2496 and DCX2496 schematics.

If someone can have a copy or a scan, I'll would appreciate very much.

Thanks in advance.

 

[Petter]

There are several parts in there that are unsuited for a cost-no-object modification.

I would advice that you consider building a complete DAC/output filter from scratch. I am currently getting started on this.

It is not all that hard since you don't need to build the full DAC with input receivers etc.

Petter

 

[lucpes]

...The desoldering is no fun.

Use a pin (needle) and gently lift one foot at a time if it's smd. Works everytime like a charm for me.

Back to the original topic, OPA2132 is a good choice. OPA2134 may work too.

 

[Gordon McGregor]

RE: op amps

Three suggestions .
1. Expensive one : use 2*OPA627 instead of NE4580/JRC4580/NJM4580 with such kind of adapter http://www.referenceaudiomods.com/images/products/audiocom/opamp627_s.jpg
This is the best solution, IMO.
2. Significantly less expensive, but still worth to use - if your 4580 are SOIC, that without any problem, if they are DIP (most probably), use SOIC->DIP adapter, as this one, for example: http://members.cox.net/alexhardware/images/AD797.JPG
and op amps AD8066 ... if your supply voltage is <12V even better solution is AD8620 ...
3. OPA2134 is a bit better then OPA2132 (IMO), having almost the same parameters, but being specifically designed for audio applications, as stated in TI Audio solution guide (AFAIK it means more even harmonics, then odd, but I am not sure 100% - at least in the specifications for "audio" op amps one can find the graph for 2nd harmonics and 3rd instead of the common THD vs frequency graph, which doesn't separate even and odd harmonics).
Another point - in some schematics OPA2134 can oscillate, where OPA2132 will still be stable ... as stated here:
http://tangentsoft.net/audio/opamps.html
I haven't been able to see OPA2134 oscillating though ...
We have to know that OPA2134 has 5 times more distortions at the high frequencies then OPA627:
http://www.dself.dsl.pipex.com/ampins/webbop/2134.htm
http://www.dself.dsl.pipex.com/ampins/webbop/opa627.htm
Though both of them - OPA1234 and OPA2132 are still claimed by some extreme modders "on the list of shame":
http://shop.store.yahoo.com/yhst-9053161298275/opamps.html

The Op Amp list of shame: NJM5532, NE5532, LM318, OPA2134, NJM2114, NJM4558, NJM4560, OPA2132, AD827, OPA2604, LF353, OP275, OP275, AD712

But IMO OPA2134/OPA2132 are not the best, but still superior in comparison with 4580, the spectrum of the last one has a lot of higher harmonics, IMO the reason of "artificial" sounding ... http://bono-www.ss.titech.ac.jp/~hajime/uec/distortion/opa/4580_f.gif
The good article about higher harmonics in op amps and advices in selection of them is here:
http://headwize.com/projects/showfile.php?file=opamp_prj.htm

 

[lucpes]

Yep, have had only good results using OPA2134.

AD8620 is +/-13V max. Hard to get and rather expensive .... samples?

 

[stef1777]

DCX2496 (as DEQ2496) use SOIC chips... You need 17 in fact for the DCX2496.

Think to the AOP2604 too.

 

[stef1777]

I have OPA2604AU in my DEQ2496.

Works fine and realy better than original JRC458 opamps.

 

[Greggan]

Maybe AD8066?

Have anyone tryed this one??
it is a sister to AD8065 witch is higly regarded acording to LC audio www.lcaudio.com

 

[stef1777]

Re: Maybe AD8066?

Have anyone tryed this one??
it is a sister to AD8065 witch is higly regarded acording to LC audio www.lcaudio.com

You can't.

DCX and DEQ use +/-15V. AD chips need 12/13V max.

We successfuly installed OPA2604 (output) and OPA2134 (input) inside a DCX. I personaly have OPA264AU inside my DEQ.

This is difficult to do. You must have the right equipements to unsolder and solder SIOC chips. The circuit board is realy fragile.

7 chips to change in the DEQ. 17 chips to change in the DCX.

Good luke.

 

[sanford1]

I've gotten some AD8620 samples from AD and will probably try them out in my Sony DVP-NS755V. My current favorite is the BB OPA134/2134. Either one should work well for you.