If it is just the top screws giving you trouble, you don't need to remove them to get the board out. I didn't. I just removed the bottom and the nut on the loudness pot, then pushed the wires to the AC connector back a bit and slid the board up and out (after removing the screws on the board posts and the heat sinks of course).
You could aslo add the Vbe multiplier bypass caps on the top of the board. The leads of the transistors you need to connect to are accessable on the top side of the board, although it gets to be some pretty tight soldering in a couple of places.
Terry
Wow, where to begin? I know - thank you so much for all this information Terry. Since you're knowledgeable about electronics (more than I am), you may not realize how enlightening and extremely useful all this information is to me and others participating in this thread. I have no problem getting the bottom screws out, I do it all the time to switch the jumpers or change op-amps. For some reason those top ones on my I+ just seem to have been tightened too much. Anyway, I have a really good soldering iron/station, plus smaller tips, and at this point I've been soldering for years and I'm pretty good at it, so it shouldn't be a huge problem.
I've done enough research and and experimenting with capacitors recently to have a decent idea about what to use and what not to use. Unfortunately, the vast majority of what I'd love to use here - V-Cap, Audio Note, etc - is WAY too big to fit inside the I+. :sigh: I do have some of the .1uf Mallory metal film caps that I've used on the op-amps, those should do the trick adequately. But by bringing this up, you have infected my mind with the idea, and I really want to do it now.
Such a simple thing, such a good idea.
And your assessment of "straight wire with gain" sounds right, and that seems to be a desirable thing, But as you mentioned, coloration plays a role, and its a fine line between what is perfect and too perfect.
There's what I call "boring neutral." One would naturally think, neutral is neutral, either the sound is colored or it's true to the source. I think it's more complicated than that. We can't have a perfectly transparent headphone amp. In trying to getting as close to that ideal as possible, we could inadvertently sacrifice some of what gives the music life, and end up with a cold, analytical sound that theoretically is neutral, but perhaps missing small yet critical things that allow us to really enjoy the music. There's a lot more than tubes in this amp that will definitely color the sound; can you say, electrolytic capacitors? :scratch2: That said, I still take Terry's point about removing the tubes to reduce coloration as a true one. I wonder though, given what's left thereafter, what cannot be removed, maybe the tubes are playing a beneficial role because of those circumstances (like the inevitable capacitors, the transistors, resistors, the shunts, and so on).
To Mr.Lin, you mentioned needing a new screw for your little dot 1+, have you checked the bag that had the audio cable and jumpers in it? mine seems to have about three extra in there...If yours doesn't, I wouldn't mind supplying one, since i'd hate to have to deal with a stripped screw, from experiance, they are no fun
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I didn't see one, but then again, it was only with the help of an Aker that I realized where the extra shunts were. :tears: I should be ok, but thank you for that offer, I do appreciate it.
