[mnemoniak]

In fact, I don't really get it, what each of those amps are doing, on the card, one amp is in front of the two others which are in line, on the HD2 advance, there is one 2604 and two 2134.

 

[majkel]

I was unprecise. The LT1264's sounds are not blurry, it's imaging is a bit blurry, not so precise. I know why people like it and I understand it but above some quality level this op amp's signature becomes a bottleneck for the device. However I'm not sure it will be the case with the HD2. Regarding the LM4562 - the guy who told me about the OPA2604 + AD8022 results, also tried this combination. LM4562 is a bad op amp, especially would be for the LT1364 fans. Actually, for spectacular effects you need to mix two different op amps and include proper supply bypassing capacitors' choice.

 

[majkel]

Quote:

Originally Posted by headsocks /img/forum/go_quote.gif LOL! So you're saying that because imaging "is a bit unprecise" it will become a bottleneck? Well, that's pretty personal at least. And I thought that the LT1364's presence (which is how I'd call it) was a wonderful thing, period.

There is nothing like wonderful presentation of an op amp. I hope you'll realize this some day. LT1364 might do the trick but I heard much better combination than LT1364 alone, and not involving the LT1364. It's a good op amp indeed, but I prefer the AD8599 to it, being somewhat similar.
Quote:

I don't know if it's a "formally perfect" representation what you're looking for, but me, what I'd look for in high-end audio would eventually just be more emotion. That's what music is supposed to be about.

So, believe me, it was to few emotions for me from the LT1364 and that's why I moved to other solutions. Unfortunately unfeasible in the HD2.
Quote:

Regarding the LM4562, the (better) LME49720 is nothing like a bad opamp. It's just a little cold sounding without too much presence - that's why it works wonderfully with the LT1364 (one after the other). The resulting sound is very very convincing, believe me.

I would never believe a midrange color killing op amp like LM4562 could sound good anywhere. Huge bass, overephasized articulation and cold, grey midrange - that's it. All the LT1364 can do is warm up and colorize the midrange but I don't believe this is true timbre instead of LT1364 timbre.
Quote:

Finally, regarding the OPA2604 - is it really that good? I haven't thought so since I replaced it with a TI 5532 in a Rotel RCD950 and the 5532 sounded more precise.

Why do you replace a bipolar input op amp for a FET input op amp? You don't need doing this. You can find my posts in this forum where I say that I prefer the bipolar op amps if only I can use them because they are more transparent IMHO.

 

[majkel]

I didn't know the LME49710 sounds different from the LT4562. Everybody reports it's the same, just single/dual difference.
OPA2604 is my favourite FET input op amp, and I cannot use a bipolar one there due to high input currents. It's I/V stage in my CDP. If I don't have to - I don't use OPA2604 neither any other FET input op amp. And it's not great alone but paired with another one, i.e. AD8022 - sounds good.
Regarding emotions - I don't think we call different things with this word, it's more probable we obtain different results due to different applications. I mostly tried the op amps in my CDP and preamp/headphone amp circuits. If the results repeat which I mean same sonic impact, then I think I know what the certain op amp sounds like.
If you haven't tried the AD8599 - please do and compare it to the LT1364. What I like more about the AD is cleaner, more delicate trebles, while preserving overall warm presentation. Imaging is slightly better as well.

 

[majkel]

LT1364 has got corrupted, unnatural treble timbre. Listen to some hit-hats, other percussion. There is a false tint. I understand your love (whoever I'm writing to now) for the LT1364 but other parts give better results in my system. I like it that you're happy with the LT1364 in yours, if you tell me AD8599 suits worse, I'll accept it and it won't change a single thing in my looking at sound.
Actually I think LT1028 is better, more transparent, but it didn't work either in my final solution. It's all about the synergy, so I can even accept the point of view that the LT1364 is best dual, where I'll still insist on AD8599's supremacy, and there is another, which has been my favourite single op amp for ages - AD825, try this as well. NelsonVandal reported that AD8599/AD825 combo is the most natural op amp combo for virtual ground headphone amps. This might be true.

 

[jamato8]

Try the opamp with a 20pf from pin 8 to pin 4. this is a bypass for the dc in and can clean up some of the white noise that can "corrupt" the sound. This is done right on the adapter board with the shortest leads possible. You can also try a .001. I used a 47uf HiQ Black Gate and a .47uF like this with good results.

 

[mnemoniak]

After having read advices here, I ordered samples of LT1364s, two is the maximum, i will test them with the LM4562 on my prodigy HD2, come what may, I can't try AD's8599, they are not in DIP-8 format and I am not able to put them on SOIC to DIP adapters.

 

[GuyMe]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif The best PROVEN combination for Prodigy HD2 is 2x OPA2604 + AD8022, period. I know, the guys haven't tried the LT1364 but I'm still not expecting it to be better. Cascading the same op amps can't produce best results as the same sonic effects get emphasized, instead of some sonic compensation and synergy.

The AD8022 is not available as a dip, what other opamp could you reccomend in its place with the OPA2604?

 

[GuyMe]

Quote:

Originally Posted by XTC /img/forum/go_quote.gif LT1469, try it. Also try the [very transparent sounding] LT1361.

This lead me to do a few searches and I think 2xLT1364 and a LT1361 might be the best combo for me. Thanks for the tip.

 

[jh4db536]

the LME49710 is awesome for clarity, detail, and decongestion. I like it better than 627BP, AD8610 by a longshot.

I think the LME synergizes perfectly with the HD6x0 and my HFI780. I HATE it with my 701. It has like zero bass impact and sounds way too thin.

 

[d-cee]

I just got the LME49710s and installed them in my PPAv2

Compared with OPA627 they are a cooler sounding opamp

IMO the OPA627 are very detailed but not in your face so, the LME49710 with its more upfront presentation seems a bit more detailed but I'm yet to be decided.

Slightly prefer the OPA637 w/ OPA627 in ground.

Still overall prefer best the comp pin out of the AD744 w/ AD829 in ground.

These impressions are based on a PPAv2 so YMMV.

 

[kunalraiker]

Quote:

the LME49710 is awesome for clarity, detail, and decongestion. I like it better than 627BP, AD8610 by a longshot.

I think the LME synergizes perfectly with the HD6x0 and my HFI780. I HATE it with my 701. It has like zero bass impact and sounds way too thin.

I would agree on this, found the soundstage to have more depth on my Grado's,the OPA604's did have more speed.

 

[ROBSCIX]

I am a fan of the LME49710, usually opting to use dual LME49710HA's over dual channel chip version such as the LME49720.  I do like the TO-99 version over the DIP or SOIC versions.