OTL Asylum OTL, Output Transformerless Amplifier User Group.

---

[ Follow Ups ] [ Post Followup ] Thread: [ Display  All  Email ] [ OTL Asylum ]

---

[ Alert Moderator ] [ Edit ] [ Delete ]

---

Re: Question for Mark Gilmore

0

Posted by mark on March 3, 2000 at 13:53:32

In Reply to: Question for Mark Gilmore posted by Marty Bronstad on March 3, 2000 at 12:55:31:

It's of primary importance to realize that my article was written for the true tweak and can even border on the need for a 12 step tweakers program. You may safely run just about any tubes you want with good results. If you're looking for only the best performance and reliability, then this tweak is for you. As with all good tweaks, you must often pay the price. It's not unusual to go through a lot of 50 6AS7Gs before you find a set that meets the 20% matching criteria. In a perfect world, every 6AS7G would want the exact same amount of plate current at a given bias voltage. You're close to 50% of your 6AS7Gs matched within 20%. This isn't too bad.

I've tried almost every brand of 6AS7G out there at one time or another. No particular manufacturer seems to do any better than about half a given lot of tubes within 20%. Often times, matching is even worse.

I can't speak for New Sensor's return policy. You'll have to discuss your desires with them directly.

It's difficult to speak to whether it's better to have a group of "high bias tubes" or "low bias tubes". It's the combination of both that is the problem. The low bias tubes will cause the high bias tubes to work too hard and the high bias tubes will cause the low bias tubes not to work hard enough. Remember, if you're dealing with averages. All low bias tubes may average out well to a median of 75 mA. The same is true for a set of high bias tubes.

Just remember, it can always be much worse. I like to match my MP-1's Mullard 12AT7s within 2% and then they're cherry picked for best noise and microphonics. A tweaker over the edge you say? Most certainly, but I think it's worth it.

I hope this helps.

This post is made possible by the generous support of people like you and our sponsors:

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---