Tubelab SSE Distortion Problem

[mudiwater]

Help please, I will first say that I am a novice at best, with a few kit builds to my credit, I can follow directions and thats about it.

I have just finished up a Tubelab SSE amplifier, amp lights up seems to work fine, sounds good at low levels, but when I turn up the volume I get some pretty bad distortion, most noticeable in the bass. Very flabby, not good.

I wired it for triode mode with no feedback. I am using Edcor GXSE15-4-5k output transformers. I am driving the amp with an old Bottlehead Foreplay preamp, which sounds very good with my other amps, so i'm thinking I have something wrong in the SSE.

Any help would be greatly appreciated.
Thanks

 

[PDL]

What kind of speakers are you driving? What's their sensitivity?

 

[mudiwater]

diy scan speak, 90 - 91 db sensitivity

 

[gabdx]

Bottlehead Foreplay preamp, has great distortion and sound coloration, like a lot, I mean it.

 

[mudiwater]

I have used the Bottlehead preamp off and on for years, with many different amps, solid state and tube. It has always been a great sounding preamp. I have also hooked up my old Hafler preamp to the SSE and have the same problem, much distortion.

Looking at the wiring diagrams, I did notice that the run capacitor is shown in one diagram to be hooked to the center tap and in another to the terminal next to the center tap, could this be the problem?

Thanks

 

[mudiwater]

Help, Ideas?

The distortion is in both channels equally, would this suggest the problem lies in the power supply?


Forgive me if I'm asking a dumb question, I don't know much about electronics, but can follow directions.


I'm thinking this amp should sound much better than it does. Its quiet at idle, sounds pretty good at low levels but a little lifeless, goes from lifeless to pretty bad distortion?


Again, any help would be greatly appreciated,
Thanks