VO-BB - 20 YEARS OLD!

JTVG · Backstage Pass Joined: 21 Jun 2007 Posts: 433

I haven't even heard the Pre73 yet and I'll second what Mike says. Too many people are saying good things. As far as the buying an Avalon 737 for the processing, probably not a good idea. The compressor is very soft and the EQ, while powerful, can probably be found in a cheaper box. The preamp is nice though and having extra bells and whistles to mold the sound is a plus. I've always had some inherent noise with the Avalon that I never noticed in solid state gear. And it got pretty bad over the last year, but upgrading the tubes fixed that for me.
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Joe Szymanski
http://www.joethevoiceguy.com

Rob Ellis · M&M Joined: 01 Aug 2006 Posts: 2385 Location: Detroit

Okay the tubes are supposed to arrive today. Can't wait! I will do a before/after comparison.

Seems like I read somewhere about replacing tubes gradually instead of all at once.....anything to that? It's not what I want to do, but it seems like I read something to that effect but I could be confusing my recollections......

Mike Sommer · Posted: Tue Jun 22, 2010 11:40 am Post subject:

Never heard that before. The big rumor is that you need to let a tube burn in--- NOT TRUE. (It is electrolytic capacitors that you need burn in.)

If you are getting tubes from a reputable company, you should be good to go. Unplug the unit. Open the case, change out the tubes and test away.

Just let the tubes warm up for about 20 minutes.

It's always good to have tubes tested. This is hard to do sometimes. But if you can find a TV or Radio repair shop in town that has a tester they can do it for very little charge.
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Acoustics are counter-intuitive. If one thing is certain about acoustics, it is that if anything seems obvious it is probably wrong.

Dan-O · The Gates of Troy Joined: 17 Jan 2005 Posts: 1638

Hey, Mike, quick question: any truth to not touching the tubes with bare fingers, because the oils on the fingers can cause the tube to burst, much like when changing a headlight?

Rob Ellis · M&M Joined: 01 Aug 2006 Posts: 2385 Location: Detroit

Oops!

Rob Ellis · M&M Joined: 01 Aug 2006 Posts: 2385 Location: Detroit

Okay, I'll post some sound in a few moments.

The output level hasn't really changed, nor the noise floor....but the
sound? Yeah, I can hear a definite difference.

Rob Ellis · M&M Joined: 01 Aug 2006 Posts: 2385 Location: Detroit

Okay here is a back-to-back, before and after

http://WWW.ROBELLIS.INFO/images/Avalon_737_tubes_before_and_after.mp3

As for handling the tubes, I found this video on ehow.com where the dude has his fingers all over the tubes, so hopefully he know what he's doing

http://www.ehow.com/video_4438285_change-pre_amp-tubes-guitar-amps.html

Mike Sommer · Posted: Tue Jun 22, 2010 1:16 pm Post subject:

Rob Ellis · M&M Joined: 01 Aug 2006 Posts: 2385 Location: Detroit

Okay, esp for you Dan-O, here's a comparison of the 416 before and after

Edit: for some reason today, the 416 with the new tubes sounds very different than yesterday. I think I may have mistakenly recorded my AT 4047...anyway, here is a corrected version

http://WWW.ROBELLIS.INFO/images/Sennheiser_416_before_and_after_new_tubes.mp3

Mike Sommer · Posted: Tue Jun 22, 2010 4:26 pm Post subject:

Big difference. The new tube has a punchy mid and a little more open on the high end.

As for the tube changing dude, he didn't instill much confidence. And when you change a tube with a shield you should most definitely wipe it off. That's the way I was taught by the old tech guys.
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The Blog:
http://voiceoveraudio.blogspot.com/

Acoustics are counter-intuitive. If one thing is certain about acoustics, it is that if anything seems obvious it is probably wrong.

JTVG · Backstage Pass Joined: 21 Jun 2007 Posts: 433

I have to listen on better monitors later, but it sounds good. Really surprised you didn't get a noise floor improvement and signal boost, all things being somewhat equal, but that probably depends in what condition your old tubes were.
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Joe Szymanski
http://www.joethevoiceguy.com

Rob Ellis · M&M Joined: 01 Aug 2006 Posts: 2385 Location: Detroit

Based on my use (about 4 hours a day, max 5 days a week) my old tubes still had about
2 more years of useful life left, according to my calculations.

I am quite pleased with the sound difference, esp with my Sennheiser 416---big difference. Even the waveform looks different (more balanced) than it did.

I'm gonna say good recommendation, Joe! cool

Dan-O · The Gates of Troy Joined: 17 Jan 2005 Posts: 1638

Big difference, Rob. And, Mike, thanks for setting me straight!

Rob Ellis · M&M Joined: 01 Aug 2006 Posts: 2385 Location: Detroit

Here is an updated comparison---with a more matched second read, and a little burn-in time for the new tubes.

click here