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previous: Bob Isaacson Has anyone had any experience with ... -- 12/24/1999 5:38 AM

Re: WTB: 7591A's USED, tested and cheap

12/24/1999 3:43 PM
Farrow	Re: WTB: 7591A's USED, tested and cheap The Sovtek 7591XYZ is in fact a re-based 5881. I would use thm in my amp, but 1) the 7591 sounds better, 2) my amp is fixed-bias so I'd have to re-do that circuit instead of simply installing new Rks, 3) I'd lose output in the end since the 5881 / 7591XYZ has a lower transconductance. So that means re-doing the driver (s) as well (my amp is stereo.) In an old Ampeg or Gibson, I recommend leaving the old tubes since they're usually good, getting the adaptor for the 6GM5 from AES, or converting to 6V6. Since a lot of people seem to want nice overdriven sounds from their Reverborockets or what have you, most people go with the 6V6. I put a little laminated card in there with instructions on how to reverse the mod and my name and phone#. It takes about 30 minutes. Farrow http://www.skybolt6.com PS compared to the 6L6 or 6CA7, there are very few amps out there that use 7591s. I LOVE the tube myself. I'd like to see Svetlana make a 7591 as good as their EL34.

12/24/1999 3:43 PM

Farrow

Re: WTB: 7591A's USED, tested and cheap

The Sovtek 7591XYZ is in fact a re-based 5881. I would use thm in my amp, but 1) the 7591 sounds better, 2) my amp is fixed-bias so I'd have to re-do that circuit instead of simply installing new Rks, 3) I'd lose output in the end since the 5881 / 7591XYZ has a lower transconductance. So that means re-doing the driver (s) as well (my amp is stereo.)

In an old Ampeg or Gibson, I recommend leaving the old tubes since they're usually good, getting the adaptor for the 6GM5 from AES, or converting to 6V6. Since a lot of people seem to want nice overdriven sounds from their Reverborockets or what have you, most people go with the 6V6. I put a little laminated card in there with instructions on how to reverse the mod and my name and phone#. It takes about 30 minutes.

Farrow
http://www.skybolt6.com

PS compared to the 6L6 or 6CA7, there are very few amps out there that use 7591s. I LOVE the tube myself. I'd like to see Svetlana make a 7591 as good as their EL34.