Triaxis OpAmp (s)

[Mandarine]

I have read the posts about swapping the stock IC3 TL072 with a Burr Brown OpAmp and the posts intrigued me enough to give it a try. After I removed the top and bottom covers I found to my surprise no less than 8 TL072 OpAmps on the main audio board (IC1 - IC8). I have looked at the schematics available and no where can I see all these - only IC3 the pre-drive to the dynamic voice OpAmp (IC3) and one in the record output circuit. What are all these IC's for?? :shock:

I worked my way through high school in an electronics shop repairing audio and video equipment, but I think I will pass on the IC3 replacement. The double sided circuit board and tight space make it an iffy (at best) proposition to try to swap this thing out without overheating the chip, or melting some insulation from the cable leads in the immediate vicinity of the chip.

I think I will investigate tube options for V3 to lower the gain before the dynamic voice input. Anyone have suggestions for what they have tried in V3? Has anyone tried dropping to a 12AY7 or 12AV7?

Thanks much.

 

[Martin]

Mandarine,
The job is not that difficult and trust me, it's worth the hassle...fit a socket. That way you can audition different chips.
Burn the chip in for 24 hours with a looper if you can, these get better as they burn in.

I have to throw my hat in the ring and say it's well worth it.....your choice !