[henree]

Been happy with the m8083 and opa 2107. But I still want more bass. Any other tubes I should try?

 

[shipsupt]

Been happy with the m8083 and opa 2107. But I still want more bass. Any other tubes I should try?

Have you tried the Amperex 6AK5W? They seem to be reported as the bass kings on the LD I+. I just got a set, so I can't confirm yet.

 

[rbf1138]

Just received my OPA2107. Could someone explain precisely how to install this correctly? 
 
Edit: ok, got it in. 
 
I feel like if anything it sounds more harsh than the stock opamp? Less warm, rougher treble.

 

[shipsupt]

Just received my OPA2107. Could someone explain precisely how to install this correctly? 
 
Edit: ok, got it in. 
 
I feel like if anything it sounds more harsh than the stock opamp? Less warm, rougher treble.

Interesting. I find the 2107 pretty warm compared to stock. When you say the treble is rough, are you meaning grainy?

What tubes are you using with it?

 

[rbf1138]

Stock tubes. Yeah, a bit grainy, a little less pleasing. Not as much air and warmth.
Quote:

Quote:

Just received my OPA2107. Could someone explain precisely how to install this correctly? 
 
Edit: ok, got it in. 
 
I feel like if anything it sounds more harsh than the stock opamp? Less warm, rougher treble.

Interesting. I find the 2107 pretty warm compared to stock. When you say the treble is rough, are you meaning grainy?

What tubes are you using with it?


 

 

 

[john57]

Make sure you have not bend any pins while putiing in the socket. It happens sometime you will fold the pin undertheath the chip. You also have line up the the dot on the chip with the socket mark?

 

[LugBug1]

Make sure the little ) is facing the front of the amp. Strange, I've tried the 3 most popular opamps as well as stock and the 2107 is defo the warmest! deepest soundstage too.
 
Havent tried it with stock tubes though 

 

[rbf1138]

Would not having put the clamps down on either side have made a difference? I did that and it seems better now. But i thought that was just to secure it, not a connection.

 

[shipsupt]

Make sure the little ) is facing the front of the amp. Strange, I've tried the 3 most popular opamps as well as stock and the 2107 is defo the warmest! deepest soundstage too.
 
Havent tried it with stock tubes though 

X2^
I had the same thought late last night, it is directional. Not sure what the result would be if it was put in backwards.

As for the clamps, my version doesn't have them, but if they are there I'd use them. I would think they are only to secure it.

 

[rbf1138]

Definitely had in the right way, and all legs in place. After using some deoxit on the tubes (stock) and a/b'ing with the opamps, I still prefer the stock. And yet, something seems off. It's not quite as full and warm as it was when I was first using it. What sorts of things should I try here? Could I have done something in removing/swapping anything?
 
This is the opamp I bought:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260655044299&ssPageName=STRK:MEWAX:IT#ht_680wt_1119
 
Also bought these but haven't got them yet: http://cgi.ebay.com/Vacuum-Tubes-6028-408A-JAN-PHILIPS-5-PC-NIB-/330563397291?pt=Vintage_Electronics_R2&hash=item4cf71d26ab#ht_1481wt_885
 
And are these the good Mullards everyone talks about?
 
http://cgi.ebay.com/CV4015-M8161-EF92-9D6-MULLARD-QDD-TUBE-VALVE-NOS-E-PAIR-/390210592843?pt=UK_Consumer_VintageAudio_RL&hash=item5ada5d204b#shId
 

 

[REDH0RN]

Mine came from here; http://cgi.ebay.com/OPA2107-dual-Low-Noise-Difet-Precision-OpAmp-DIP-8-x2-/170632916927?pt=LH_DefaultDomain_0&hash=item27ba83afbf#ht_2510wt_967
 
Noticed sound improvement immediately.

 

[rbf1138]

Thanks...just ordered one, figure can't hurt to try a different one out.

 

[shipsupt]

Seems hard to believe you got a bad one, but I do recall at least one post early in this thread when someone felt they had a bad opamp.  I guess it can't hurt to rule it out.  It also seems pretty difficult to have induced a problem, but again not impossible.
 
There was one guy early on in this thread who found his transformer was set to 220V, so he was having many issues before he narrowed that to be the problem... seems like a reach, but it wasn't until he started rolling op-amps that he noticed it.  He was amazed that it sounded pretty good with the wrong voltage setting, but was amazed at how good it was when he got it right.
 
Those 408A's you got should be solid performers.  Some folks prefer them to many other tubes.  I've not given them much time in my amp, but I ran one set for a while and was, as I recall, pretty happy with the sound.
 
Those Mullard's are well thought of, but I'd think you could track them down cheaper either by waiting on some appearing on ebay or by emailing a few tube sellers to see if they have them. 
 
It interesting to hear that you are hearing a difference now in your stock op-amp.  Makes me think there might be something else going on... but what I can't quite put my finger on.  Certainly it will be good to try another set of tubes just to rule that out as an issue.  I assume you are trying a few of your headphones and noticing the same thing no matter which you choose? 
 
For the sake of good order, have you checked all the jumper/switch settings to be sure they are all correct?  Both for tubes and gain?
 
Sorry not to really offer much help!!  Hopefully you'll narrow it down by carefully ruling things out.
 
 
 

 

[john57]

I would recheck everthing and make sure the jumpers(tiny black clips)  are fully in place. It does seems that maybe something was amiss while you were changing the opamps. The first site you got was the TEXAS INSTRUMENTS stamp and the other site has the BB stamp.  Texas Instruments brought out BURR BROWN  some time ago.                    

 

[LugBug1]

Enjoying some matched Mullard EF95's. Very warm but detailed, probably the most tubey sound I've got yet. Goes well with op2107 if you are after more warmth with Grado's.