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

The following is an excerpt from an email that I sent to a customer - I 
was too lazy to type it all out but it briefly summarizes info about 
tubes


Tubes -- the tube tones vary mostly depending on their source. Chinese 
tubes are the cheapest and have the highest gain but they have the 
glassiest, solid-state like tone. They are also pretty inconsistent if 
you buy the non branded ShuGuang-made tubes. The standard 2101 has 
Chinese made tubes that are "matched" by Penta (in California). Russian 
tubes have almost as high a gain as the Chinese tubes but have a 
warmer, more tube like character. All the Russian tubes come from the 
same source -- Sovtek -- and they are then re-badged by companies like 
Mesa/Boogie, GT, Electro Harmonix, etc. I personally use British or 
Japanese Mullard/Panasonic tubes in my preamps. They have slightly 
lower gain but give the best/warmest overall tone in my opinion, and 
are usually very consistent across the board. The older marshall amps 
are usually equipped with Mullard tubes but the tubes are significantly 
more expensive.

The russian tubes are a good compromise between gain and tone. There 
are construction diferences in the tubes. the GT tubes are usually 
"long plate" tubes. This makes them a little more susceptible to 
microphonics the newer "short plate" Mesa/Boogie tubes. What happens is 
that when playing loud, the vibration transfers into the processor and 
tubes and cause the plates to resonate and vibrate along, causing a 
feedback like tone. This becomes a problem especially for musicians 
unfamiliar with their tube preamps and leaving them sitting on the 
combo amps or speakers.

Hope this helps

Adrian Teo
Function7 Engineering


On Nov 12, 2006, at 8:23 PM, dunkin_donut3 wrote:

> Thanks everyone!
>
>  I do have more than a handfull of 12AX7's, 12AT7's, 12AY7's and some
>  6201's. Some are vintage, some are new and some are NOS. I've been
>  switching various tubes in and out all day and I'm still not sure 
> which
>  way I'm going to go.
>
>  I guess I should have given everyone a bit more background on my
>  playing style but it would suffice to say I use my 2101 for everything
>  from Jazz to Country and everything in between. I love these things.
>
>  Again, thanks for all the help. I'm sure I'll have some more questions
>  as time goes by.
>
>  Dunkin
>
>  
>