OPA2134 vs. AD8610

I planed a while ago to replace my OPA2134 in my Pioneer AX10 to the OPA627. Unfortunately the single to dual adapter I looked at simple didn't fit into the very tight space of the AX10. Now I noticed that Browndog has a very compact adapter for this purpose, so I'm considering do give it a try again. If I do, I think I will go for the AD8610 instead for the OPA627. Do you guys have any comments on that? Will the AD8610 be suitable as both an I/V and filter replacement for the 2134?
 
I will check the voltage out and see if the 8610 are suitable.
Regarding my filter question. As I don't know which of the four 2134 per channel that is for I/V conversion and which are (if they are?) the filter, I was thinking about replacing all of them. Do you see any problem with that?
 
I have not upgraded my CD player yet, so I do not speak from personal experience, but judging from the spec sheets and the outstanding performance of the AD8610 in other applications such as a headphone amp I am building, it is probably a great choice for the I/V converter, filter, and line out of the CD player.

I have a Denon DCD-1420 which uses various Japanese opamps such as the 2068, 4556, and 4570. I'm not sure how much of an improvement the opamp swap will achieve, but it will be interesting to see. I'm not expecting miracles, but more sweetness and less grain would be nice.

The circuit board for the CD player headphone out section is upside down, inaccessible from the main compartment, and requires major disassembly to get a look at. I might be tempted to use an opamp with higher output current for the headphone out if the opamp drives the headphones directly, but if the opamp is buffered then the AD8610 is probably the best choice again.

There are many good opamps to choose from, get a variety if you can, and compare them. The differences become subtle at a high level of performance. I'm in the process of comparing several opamps for use in headphone amplifiers and CD players, including the AD8610, AD825, AD8512, AD823, AD826, OPA2132, and a few others. I've also been working on a custom audio test tone CD to help evaluate the opamps and the CD player. So much to do. :)
 
bmwrob said:
I planed a while ago to replace my OPA2134 in my Pioneer AX10 to the OPA627. Unfortunately the single to dual adapter I looked at simple didn't fit into the very tight space of the AX10. Now I noticed that Browndog has a very compact adapter for this purpose, so I'm considering do give it a try again. If I do, I think I will go for the AD8610 instead for the OPA627. Do you guys have any comments on that? Will the AD8610 be suitable as both an I/V and filter replacement for the 2134?
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The 8610 sounds better than the 627 as both filter/buffer and I/V. If it s I/V, a faster settling opamp than the 627 or 8610 appears (and sounds to me) desirable.

Use the 825 or 826 for I/V
 
ad825 vs ad8610

Hi Fmak,

thanks for all the ongoing help.

I replaced my ad8610 I/Vs with ad 825s last night.

so far I note that the ad8610 seemed to go deeper in the bass and is a little warmer overall than the ad825.

The ad825 seems to be more detailed alright. I am curious to see if this impression changes over the week.

Have you found anything similar?
 
Re: ad825 vs ad8610

PhopsonNY said:
Hi Fmak,

thanks for all the ongoing help.

I replaced my ad8610 I/Vs with ad 825s last night.

so far I note that the ad8610 seemed to go deeper in the bass and is a little warmer overall than the ad825.

The ad825 seems to be more detailed alright. I am curious to see if this impression changes over the week.

Have you found anything similar?
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Glad you fixed the player. It takes about a week for the new opamps to settle. I found the 8610 to be better as filter than I/V; and a bit less open than the 825. Can't say there was much in it in the bass. This nwas not for the 777 but for a diy upsampling DAC.
 
Well I couldn't find them at RS or Farnell, but I sent them a mail and asked if it was possible to order them. Nevertheless, I also found the AD8620 on AD's homepage. As they are dual amps, they are more or less 'plug n play' which for me is good. Do you have any concerns about that? I was also considering using a socket so I easily swap back and forth without any need for soldering. Is there any drawback with this?
 
hifi said:
Anyboddy tried BB OPA637??

/micke

i've tried the 627, which is the compensated version of the 637, but it wasn't stable in my application (was a power amplifier input stage though). i hear the AD825 is hands-down just better. the 627 is very expensive too. if you want to try it, i would recommend against the 637, as it is not unity-gain stable - stick to the 627. you do not need the extra bandwidth of the 637.
 
dorkus said:


i've tried the 627, which is the compensated version of the 637, but it wasn't stable in my application (was a power amplifier input stage though). i hear the AD825 is hands-down just better. the 627 is very expensive too. if you want to try it, i would recommend against the 637, as it is not unity-gain stable - stick to the 627. you do not need the extra bandwidth of the 637.
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Despite the precision title, I don't find the 627 to sound good at all, in many applications. The opamp is very quiet, analytical, but very hifi - sounds like a better version of the 5534. I think this may be due to the high gain of over 100dB or over and not so great settling, especially in the I/V position. Even as filter or buffer, there seems to be an edge or grain at mid/hi. I always end up removing it.
 
single so8 to dual dip opamp adapter available from BrownDog

The AD8620 is still vaporware, don't hold your breath on it appearing anytime soon. However, both the AD8610 and AD825 can be made dual dual dip compatible using the BrownDog opamp adapter. I posted this on the Solid State Forum a while back, before I knew this forum existed. The index on the front page does not list Electronics and parts. Anyway, here it is again:

[IMGDEAD]http://www.brndog.com/Images/020302a.jpg[/IMGDEAD]
[IMGDEAD]http://www.brndog.com/Images/020302b.jpg[/IMGDEAD]

http://www.brndog.com/SingletoDual.html