Sony vFET Illustrated build guide

Amplifier chassis question:
would this be a good or bad idea?
1.moving transformer into separate chassis, keeping away from the amplifier.
2.making the amp chassis from non metal material (aside from heat-sinks) to improve vibration control and remove electrical/magnetic interaction between chassis and circuitry

thanks,
Herman
 
Amplifier chassis question:
would this be a good or bad idea?
1.moving transformer into separate chassis, keeping away from the amplifier.
2.making the amp chassis from non metal material (aside from heat-sinks) to improve vibration control and remove electrical/magnetic interaction between chassis and circuitry

thanks,
Herman


#1 Always desirable but I doubt necessary with this build.

#2 Not really sure but I doubt necessary with this build

The store 4U chassis is more than adequate for this amplifier.
 
Ok, it looks like it is the front end. I played music through it and took voltage measurements at the RCA jacks and at G-T18 on both channels I got ~100mVac at the input jacks on both channels, on the good channel G-T18 was about 400 mVac and jumping around. On the bad channel I got 0 mVac. It looks like I need to pull the JFETS. Thanks

Your DC values look good. Double check your R1 thru R4 resistor values. Can you measure the AC value at the gates of the input jfets, to make sure signal is getting to Q1 and Q2.
 
Bridging

I'm making 2 "stereo" amps and I intend to bridge each one to effectively make
2 mono amplifiers. I'm currently putting together a Digikey order for all the parts I don't have (mainly for the PS boards) but I'm just wondering whether bridging will necessitate any component changes / additions, or is it, as I believe, just a question of wiring the input and output for bridged operation?
 
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I'm using 8*33000uF in my amp's PSU. I like big caps and cannot lie...

The only real potential drawback I can think of is higher inrush current. Some people argue that higher PSU capacitance involves sharper current draw peaks when the caps recharge. The sharp peaks have more higher frequency content (think FFT) than for example a wider peak that you'd get with lower capacitance. The higher frequency content may get passed on by the following regulator. Apparently the effect is measurable in some applications. I wouldn't lose sleep over it in the present application. Another potential drawback is that bigger caps can - given the chance - result in bigger explosions.