Vibrolux 6G11a low voltage. Replaced transformer. please help..

[Ampig]

I replaced the burned up transformer on this 6G11a vibrolux and I have low voltage (180vdc) after the rectifier gz34. If I use a 5u4 I get about 290vdc. If I measure the voltage with the amp out of circuit, I get ample voltage (360vdc). What would cause a halving of my voltage? The transformer is a new hammond replacement and tests good. Am I missing a resistor that would drop the voltage?

[tubeswell]

How old are the filter caps? If it is a real 6G11a, then they might be really-old caps that need replacing.

[txstrat]

Do you know why the transformer burned up? The GZ34 might be bad, cause generally a 5U4 drops more voltage than a GZ34.

[Ampig]

The filter caps are new. I installed 100 Uf in the first stage of filtering and 16 Uf in the last three. I installed 100 Uf because there was line noise (hum) when using the stock 16Uf in the primary filter. This did not effect the voltage by using higher value caps.
The old caps were whipped and took out the power transformer. There was a solid state Rectifier that I think was also a culprit in the demise of the original PTrans. This amp has no standby switch so it just slams the caps when you turn it on with a solid state rectifier.
It seems that when I install the power tubes, it pulls down the voltage from 450vdc to 180vdc. This is normal, but to pull it down to half of the required? This is the response of the 5AR4 that I have as a rectifier. The 5U4 doesn't let the voltage down past 290vdc.
Not only am I confused, I am an amateur. I don't know which is worse.

[Ampig]

I suspect that the GZ34 might be bad but I just bought it brand new.

[pdf64]

100uF is too much for a gz34, use 47uF or 2 parallel 32uF.
http://www.mif.pg.gda.pl/homepages/f...035/5/5AR4.pdf
Take the power tubes out and measure the B+ with your GZ34 and 5U4. Suspect your GZ34 is bad. Peter.

[txstrat]

This amp has no standby switch so it just slams the caps when you turn it on with a solid state rectifier.

As long as the voltage rating of the caps is sufficient it shouldn't harm the caps. Every other amp with a solid state recto and a cap before the std by switch has to deal with this.

It seems that when I install the power tubes, it pulls down the voltage from 450vdc to 180vdc. This is normal, but to pull it down to half of the required?

Did you try new power tubes as well?
When tubes go down they can take the PT with them.
Bad power tubes might explain why the GZ34 drops the voltage to 180v.

[Ampig]

I did try another set of known good power tubes. No change in voltage. I am going to order another GZ34 along with some other stuff. We'll see if that does it.