Modification for A15Mk1

MAD

All,
for all A15Mk1 owners wanting to modify their Amp to an A15Mk2, I've added in the gallery
http://forum.musikding.de/gallery/thumbnails.php?album=124
schematics and layouts for the following three modifications:
- changing tonestack channel 1 (more bass, better control)
- changing the reference for the heater voltage (precaution to enhance tube life)
- changing the layout of the "mainboard" (reducing crosstalk)
The last modification is recommended for all owners of an A15Mk1 bothered by the crosstalk on channel 2 (guitar sound but volume turned to zero)
Following the music fair a complete guide and part set will be available
Regards,
Martin

david_djd

Re: Modification for A15Mk1

humm.. :).. i think that i'm gonna have some fun here.. thanks Martin

polifemo

Re: Modification for A15Mk1

Looking forward to that (I received my A15Mk1-kit the other week, but have decided to wait with the build until the Mk2 guide + footswitch is out.

kwoizoad

Re: Modification for A15Mk1

these mods are they also change the difference in volume between ch 1 and ch 2?
if they do, i've rev. 1.4 but my mainboard looks nothing like the mk2 layout.
Do I have to change the whole mainboard or one a few components?

kwoizoad

Re: Modification for A15Mk1

anyone.....?

Alexx

Re: Modification for A15Mk1

You cant change the maximum volume of the cannels because channel 2 has way more preamp gain than channel one...

mathieu2703

Hello, I need to have the modification of the layout tonight (I have just tonight the amp that I made for the club of my school), but the gallery is unavailable!!!

Do someone have the modification of the layout, or the A15mk2 layout to send me please? By mail ou by private message?

Thanks a lot!

maumari

hi mat, how can I send you the tonestack mod images?

mathieu2703

Thanks a lot, but Klaus Brunner sent me the A15mk2 documentation. Thanks to him too.

Jetzt mitmachen!