Thursday, December 31, 2009

Plexi Jr Build.... It's alive!!!!!!!!!!!

Plexi Jr Build - Day 1

So, it took almost two whole day to finish it all up! but for the first fire up, smokes came out of the Power transformer!!!!!! damn!

Troubleshoot it with the help of Razi for a couple of hours until i realise that the rectifier used was not compatible with the PT. took out two of the 1N4007 off the ground and no more smoke...

but wait! the tube won't light up! tried bypassing those 100R (R1 & R2), and also no connection between pwr tube's pin 8 and filamen lines, but still to no avail!

turns out that connection of pin 8 and filament lines was suppose to act as an artificial center tap, but my PT already has a center tap for the low voltage 2ndary!

but that wasn't the problem though....

The problem was simple. I didn't forced the tube into its sockets hard enough! I had to go to Razi's house to know about this! haha

How does it sound now? couldn't really say much now. too early to tell much. caps havn't burnt in yet and all..

but lots of bottom end for sure. the TMB does make the tonal possibilites wide. overall volume output is not that loud though.

but the gain! it does has a lot of gain. but won't be able to reach into metal territory though without any pedals. great classic rock (say led zep) tones though!

with my modded TS9 in front, it really is a rock monster! not really metal territory yet, but for those modern rock tone, it's great!

so i pushed it with TS9, now i push it harder with my Dr Boogie! with it's gain set below 9 o'clock, the amp turned into a metal monster! Muahahaha! lots of gain with bottom end that the Plexi Jr has! Krraaannnnkkk!!!!!!!

however, the only problem now is the bias. the stated schematic cathode resistor gives too cold of a bias (around 10 watt instead of 14watt plate dissipation voltage). this would probably be because my PT's HV 2ndary is 220V while in the schem is260V.

probably it'll sound better after biased right?

Soundclips/vidz would be up when i hav the time. for now, below are some pictures!







1 comment:

nikorgbroga said...

Nate, bahasa teknikel. Aku tak paham langsung. MUAHAHAHA!!