[gibosi]

It really does come down to synergy. My default tube, a Holland-made E188CC, has a glorious wet mid range with great liquidity and flow. Putting the 01 in, there was less flow and the mid range was a bit drier. Putting the 02 back in, the flow came back and mid range was glorious again. Some example tracks:  James Blake's Overgrown album - 'Overgrown', Robert Glasper's Black Radio 2 album - 'Calls', and David Gray's White Ladder album - 'Please Forgive Me'.
 
Again, it really does come down to synergy, and given my ears and gear, the 02 and the E188CC are a match made in heaven.

 

[NCSUZoSo]

Guys what would be the cause of static coming from one channel using my Creative ZXR w/ OPA627SMs and a MUSES01?  I noticed when I was trying to fit a Dual DIP8 to Single that I scratched the outer surface of one of the near by capacitors decently.  More than a scratch, more like a light gouge.  I checked continuity from the leads of the OPA627SMs and the other two Opamps to their solder points on the back the of the PCB and everything was good there.
 
I first tried to install the OPA627SMs on their own adapter, but it was too tall so I put them in the more common socket adapters.  I'm wondering if I could have gotten one of the Opamps too hot between soldering -> desoldering -> soldering.  Also when you touch one of the leads (either lead 2 or 7 I believe), is it supposed to have continuity with the metal cap?  I just now noticed this static because I used headphones for the first time in a long time last night and on multiple source files I got static out of the right channel.  I guess I just didn't notice it when running 5.1 due to all the other speakers.
 
The odd thing to me is when there is nothing being played there is no white noise or anything coming from the channel, I figured if there was a problem like that it would always be there.  If a damaged cap could do this, I can easily replace that cap.
 
The bad part is I continued my upgrade and I have 2x ADA4627-1BRZs converted to a dual op amp-DIP8 on the way here...  I'm going to feel pretty stupid if I can't solve this and I have more component upgrades on the way.
 
 
Even when I isolate the right speaker I can not hear any distortion or static coming from it, is it possible there is something wrong that is only picked up through headphones?

 

[razzz42]

My guess is you didn't cleanup the flux after re-soldering with either flux remover or some alcohol with a fine brush or light scraping with a dental tool. Even then sometimes a silicone spray is needed to preventing tracking crossover. Next guess you fried the chip. Next guess, would be a bad connection: adapter pins, headphone leads, any possible bare leads in use or not in use.
 
You should be able to find the problem by checking connections or backtracking, trying different headphones, trying good known opamps. I can't speak to a gouged capacitor but if it is not leaking it should be good.

 

[NCSUZoSo]

I think the chip itself is damaged, which doesn't upset me too much because the OPA627 isn't a very expensive op-amp these days.  I was thinking about replacing them right after buying them, how does the LME4990 perform in comparison?  Is it as colored as the OPA627SM or is it more transparent?  Is it better or worse in the THD department during actual usage, basically I know someone must own both of these and can compare them since they are so common.
 
Is there another single operational Op-Amp I should be considering besides these (OPA627 and LME49990) for my Creative ZXR?  In the rear dual DIP8 slots I have a MUSES01 and 2x ADA4627-1BRZs converted to a dual op amp-DIP8.  So anyone have any suggestions for replacing the most likely burnt OPA627SMs?
 
My only question about the issue I am having is why is there only any issue at all when using headphones?  I have isolated my front Polk Audio 45B to the right speaker only and there is absolutely no noise, not even when playing Blu-Ray audio like the Pink Floyd Immersion material.  So I don't understand how that is possible for only the heaphones to have an issue.  When I noticed the issue I was using a cheap Creative "Tactic 3D Alpha" headset, however since then I have also experienced this with my Technics RP-DJ1205s.
 
Maybe I should get two more ADA4627-1BRZ and put them in the front?

 

[Audiofanboy]

First time on this thread, please treat me nicely!

 
I just read about the positive returns on the MUSES opamps. I'm kind of curious as to what position most of you tried these in (I/V, buffer...) since I can think of at least 5 sockets where I could (re-)upgrade chips in all my gear...
 
I used to roll opamps pretty often a year or two ago, until I settled for whatever worked best on each piece of equipment I own. Namely, 4 x AD797BR on my DAC outputs, and 6 x OPA627AU in my iBasso D10 (2 for I/V stage & 4 for buffer); I had also settled for 2 x OP637BP on my Auzentech sound card before I sold it, since the circuit allowed non-unity gain opamps and that one gave me the best sound (though retrospectively, 2 x AD797 would have been just as good if not better).
 
So, I could be interested in, say, the MUSES02 in both my DAC outputs, and in either position in the D10, depending on feedback here. Any suggestions?
 
Any direct comparisons with the AD797 too? Seeing as it's kind of my go-to opamp when the circuits allow for it to work well (not oscillate or whatnot).

 

[razzz42]

I used AD797 for a couple years then switched to the MA49990 as it can go in any position with its clarity across the range, maybe a slight lack of base. OPA627 was always to colored for me, colored the entire range. Have a MUSES01 in the mail to try in the output socket to see what I think of it. Preferred the staging and highs from opinions vs the 02 warmth and bass reviews.
 
Running MA49990 in the I/V sockets and LT1028ACN8 for output (both chips need their own adapters) on a Prodigy HD2 DE card.

 

[NCSUZoSo]

Ok, well I was right about the receiver not outputting any noise on the right channel like the sound card does when I plug into the little volume control module with headphone hook ups.  The difference to the sound card is the headphone amplifiers on the card are not kicking on, so that is playing some role in creating the static.  This makes no sense to me if it was related to anything I did with the Opamps, because the on-card headphone amp shouldn't be affected by changing them (in how it works).  This really is no issue since I can just plug into my Yamaha RX-V863 to use my headphones, but I would still like to know why the headphone amp is creating noise in the signal when it kicks on.

 

[rhead]

I just got some LF411ACN from TI, can't wait to test em out.

 

[Audiofanboy]

Well, I just bought both the MUSES02 and the MUSES01 to try them out. I just couldn't miss out on all this opamp fun lol...
 
Anyway, will report back when I do get them.

 

[NCSUZoSo]

I'm happy with my MUSES01, I put it in alone just to see what affect it would have and you could tell there was better clarity and bass with it installed.
 
I'm interested to see how this final piece to my setup will play along with everything else, the 2x ADA4627-1BRZs converted to a dual op amp-DIP8.
 
I'll be running:
 
2x OPA627SM
1x MUSES01
1x ADA4627-1BRZs (duals)

 

[NCSUZoSo]

Well I fixed the problem with my right channel issue when using the on-board headphone amp on the ZXR.
 
I pulled the OPA627s and put in AD8597s in their place and now everything works and sounds great.  It seems the 8597s have more clarity over the 627s, which is what I sort of expected due to all the info on the 627s being highly colored compared to other Op-amps. I must have gotten one of the OPA627s too hot between soldering -> desoldering -> soldering again and damaged the circuit.  The AD8597s came pre-soldered onto a Brown Dog SOIC 8 to DIP8 adapter and I just had to solder on the pin headers.  One thing great about these is they are no taller than the capacitors on the board so I will be able to reinstall the EMI shield.  I'll be sure to show yall pics once my final Op-amp arrives (1x ADA4627-1BRZs (duals)).

 

[razzz42]

  Well I fixed the problem with my right channel issue when using the on-board headphone amp on the ZXR.
 
I pulled the OPA627s and put in AD8597s in their place and now everything works and sounds great.  It seems the 8597s have more clarity over the 627s, which is what I sort of expected due to all the info on the 627s being highly colored compared to other Op-amps. I must have gotten one of the OPA627s too hot between soldering -> desoldering -> soldering again and damaged the circuit.  The AD8597s came pre-soldered onto a Brown Dog SOIC 8 to DIP8 adapter and I just had to solder on the pin headers.  One thing great about these is they are no taller than the capacitors on the board so I will be able to reinstall the EMI shield.  I'll be sure to show yall pics once my final Op-amp arrives (1x ADA4627-1BRZs (duals)).

I would tell you to recheck any solder flux overflows on the adapter board's traces and clean it off but the 627 is not worth the trouble in my opinion.

 

[highfell]

Well, I just bought both the MUSES02 and the MUSES01 to try them out. I just couldn't miss out on all this opamp fun lol...

Anyway, will report back when I do get them.

Have you received them yet? What is your review?

 

[Audiofanboy]

Have you received them yet? What is your review?

 
Nope.
 
I'm not even sure whether or not China sent them yet, so reviews might have to wait a while...

 

[razzz42]

MUSES01 arrived from China but I am giving it about 40 hours of break in before saying anything about it. Sounded neutral to begin with but the lows are showing up now and waiting for some mid to high areas to fill in. Using  it in the output socket to headphones.