Bottlehead Forum

Bottlehead Finished Products => Tube Repro => Topic started by: xcortes on February 12, 2014, 07:23:03 AM

Title: Red RIIA repro
Post by: xcortes on February 12, 2014, 07:23:03 AM

The only riaa repro made fell on my lap (the red guy). This amp was done before the very high end phono tube. No chance to listen to it yet. Just tested it. Right away I measured noise. I've alway got some buzz from my cartridge/suts/eros. I've resoldered everything and checked everything again and again for years. And rebuilt the SUTs box and tried different SUTs. Always a very slight noise but present. The combination with the same cartridge/suts/repro is almost 10dB quieter. May be the layout, the shielding or just a better construction but if that's the only improvement I'll get it's worth it. And I'm pretty sure I'll get some other improvements.

I have three BH repros now. I should start looking for a shrink.

Saludos

Title: Re: Red RIIA repro
Post by: Paul Birkeland on February 12, 2014, 07:32:46 AM

Quote from: xcortes on February 12, 2014, 07:23:03 AM

The only riaa repro made fell on my lap (the red guy).

I technically have the first one.  When transitioning from the Gen 1 Repro to the new version with the custom CNC'd cabinet, I built a tube phono for myself as a proof of concept for the Tape Repro. 

There are a myriad of possible causes for quieter operation, but the full aluminum enclosure and extra distance between the power transformer and circuitry sure isn't hurting anything!

Title: Re: Red RIIA repro
Post by: Doc B. on February 12, 2014, 07:45:22 AM

Usually the cure for the noise is to keep moving the SUT around until you find a spot where it doesn't pick up as much of the magnetic field from the surrounding gear.

It is never a convenient spot...

Title: Re: Red RIIA repro
Post by: xcortes on February 12, 2014, 08:41:06 AM

Yep. I know and that helps a lot but even without much trying I got less noise with the new set than the lowest I had before. Now to listen and record all those 45rpm I have waiting on the shelves.

Title: Re: Red RIIA repro
Post by: johnsonad on February 12, 2014, 01:15:52 PM

I'm glad that you like it and that it found the right home :)

I wonder if your noise is coming from somewhere else? Recently I rearranged my Otari/ Eros combo and where it was dead quiet before, I started to have hum, enough to be bothersome. After an hour of troubleshooting the change was from the wall power. I previously had the Otari and the Eros plugged into a Premier Power Plant with no noise. The Otari at the time was plugged Into wall power. I plugged the Otari back into the PPP and the hum went away.

If it's 100% coming from the step up then I have another option for you and will email you about it tonight.