Mailist to discuss all issues regarding the Digitech GSP-2101 Guitar FX Processor

Glenn,
Groove Tubes (12AX7A) are chinese made Chuguang tubes (and other "cheap" 
tubes) with Groove Tubes branding since some time.
The chinese tubes work well for the 2101.
I can't recommend groove tubes because if you order you don't know which 
manufacturer (ans series) you'll get. So you better should order directly 
from the manufacturers and not from re-branders like groove tubes or tube 
amp doctor.
You should get some with short anodes to have low microphonic effects.The 
brand doesn't matter, but the adjustment after tube replacement should be 
done carefully.

Moreover the problem:
"The level of sound is not stable, it is low after a few minutes, it then 
becomes normal and is weak again."
doesn't seem to be caused by the tubes.
This very common failure is caused by the LDR-optocouplers in the preamp 
stage.
The problem is that the OCs are sold out long time.
I haven't found a replacement, yet.
If someone knows a source I would be happy if he drops me a line.

Thanks
Dieter


----- Original Message ----- 
From: Glenn Warner 3rd
To: gsp-2101@yahoogroups.com
Sent: Sunday, August 03, 2008 5:33 PM
Subject: RE: [gsp-2101] The problem Digitech GSP 2101


I was going to say at that age of a 2101, did you check the tubes? If you go 
with new tubes, stay away from cheap crappy chinese tubes like groove tubes, 
and others. Go to www.eurotubes.com and check their website. I put a pair of 
JJ tubes, high gain option in my 2101 and those tubes are THE BEST I have 
ever heard. There is also some maintenance info on the website that might 
help. The info might help you identify if your tubes are bad or going bad.


Regards,
Glenn

To: gsp-2101@yahoogroups.com
From: fanstrat77@...
Date: Sat, 2 Aug 2008 22:55:39 -0700
Subject: [gsp-2101] The problem Digitech GSP 2101



Hi,

I have an Digitech GSP 2101.
The level of sound is not stable, it is low after a few minutes, it then 
becomes normal and is weak again.
I cannot any more use it because this problem.
The EPROM version installed in my GS\ufffd2101 is : 1.03.02
Is hasn't the PPC-210.

Please help !!!