#1
So, I've been hoping to mod my socal for a while now and I've searched a bunch of forums. This is one of the only ones where I saw other people talking about it but there weren't really any posts of what the mods were. Could anyone help me out? I know how to do the work, just not sure how to figure out my own mods.
Thanks,
Joe
#2
What dont you like about it now? What do you want to do?
Last edited by Dr. House at Jan 30, 2009,
#3
I like it. But I always feel there can be room for improvement. I'd take the reverb out. and then if there is anyway to get rid of some of the flabbiness in the gain channel...
Here is how I run it:
JJ KT77 power tubes. I only use the gain channel on either 25 or 50 watts depending on the room. But I run both the Level and the Gain at about 3/4 up. I've heard that that could be damagaing and maybe I'd need to rebias? Not sure though.
#4
Quote by inkandlead
I like it. But I always feel there can be room for improvement. I'd take the reverb out. and then if there is anyway to get rid of some of the flabbiness in the gain channel...
Here is how I run it:
JJ KT77 power tubes. I only use the gain channel on either 25 or 50 watts depending on the room. But I run both the Level and the Gain at about 3/4 up. I've heard that that could be damagaing and maybe I'd need to rebias? Not sure though.


JJ tubes are build like brick ****houses, unless the plates are glowing red you'll be OK...most likely.

Was the amp originally set up w/ EL34s, or did it come w/ KT77s stock?
Quote by kcdakrt
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#5
It was stocked with really cheap EL34s. And I was thinking of throwing in some ECC83 preamp tubes.
#6
ECC83 are the same thing as 12AX7.
Flabbiness in the gain channel might be helped along by removing a cathode bypass cap on the preamp tube for the gain channel. You could also take a look at the filter caps, as those are usually a culprit, but that's a more expensive thing to experiment with. Removing the reverb is not going going to help with the flabby bass.
#7
I know that reverb won't get rid of the flabbiness. But its a really bad reverb and its not footswitchable so its usless to me. I'd make it an effects loop.
How would I identify the cathode bypass cap?
#8
coming off of pin 3 and 8 of each preamp tube (you'd want the furthest one upstream, or maybe the second), you'll find a resistor paralleled by what is probably a little blue cap (little blue cylinder w/ a dent around one side), probably w/ 22uF/50V or 22uF/25V on it. remove that. I recommend cutting a lead and bending it up so that you can easily resolder it if you want.

BUT...that might not cure the problem. I'll try and find a schematic for it sometime, can give you greater instruction then.

With a large (22uf = large) cap, all frequencies (that are above 20 Hz) are boosted. If you take the cap out, you loose the boost...but all frequecies are still the same gain. You'd probably have better luck switching that 22uf for a 1uF or there abouts... That would drop some bass (read that as meaning "enough to make it not flubby but still have bass), but would retain the boost on higher freqeuncies so you actually perceive a difference.

Quote by kcdakrt
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#9
I have a file of the Schematic but I couldn't get it posted online. I could send it to you if you wish. Thanks for the help.
I would like to do as much to it as possible. Some just to say I did it. Some to learn. And some because I know alot of people hate this amp but have done things to make it "better".
#10
Get a clear idea of what you want to do/improve, then PM me and we can talk.

EDIT: schematic would be great...
Quote by kcdakrt
DLrocket89 makes my ug experience better!


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