Maverick re-tube

mavuser

Enlightened Member
Joined
Sep 15, 2010
Messages
8,128
Reaction score
2,636
Location
New York
I am going to replace every tube in my Maverick 2x10. its time. i have all NOS tubes- powers, preamps, reverb...

do I need to do anything? this amp has no manual bias. I just change them and turn it on? how long should i let the amp warm up in "standby" before turning it on and playing? thanks!
 

Default

Super Moderator
Platinum Supporting
Joined
Jul 30, 2007
Messages
13,596
Reaction score
3,008
Location
Philly, or thereabouts
Guild Total
11
Cathode bias, you don't have to do anything. Change the tubes and see if anything changes, if not, leave the old preamp tubes in.
Fire it up, you don't need to do anything else. Save the olD tubes..
 

mavuser

Enlightened Member
Joined
Sep 15, 2010
Messages
8,128
Reaction score
2,636
Location
New York
thanks very much Steve. im going to swap them all and start fresh, the amp is totally refurbished other than that. ill save the old tubes, the old reverb tube is still good, and possibly the pre amp tubes (although the pre amp tubes have many miles). the power tubes are toast, im pretty sure.
 

mavuser

Enlightened Member
Joined
Sep 15, 2010
Messages
8,128
Reaction score
2,636
Location
New York
wow major difference. its running super quiet now, sounds like a brand new amp. should have done this a long time ago. they all needed swappage except the reverb tube but i put a fresh reverb tube in with rest, just to start fresh. saved all the old ones of course. she sounds raunchy now! thanks again Steve. heres a pic-

wC7zmv.jpg
 

Quantum Strummer

Senior Member
Joined
May 26, 2015
Messages
2,382
Reaction score
118
Location
Michigan
Re. standby: I typically let the power tube heaters warm up in standby for ~1 minute before switching to "play" mode. Then I like to let the amp idle for at least 5 more minutes before playing. This depends on the amp, though…some are ready to go almost immediately while some of the oldies need awhile to stretch & limber up. :)

Just noticed from the pic that your amp takes 7591 power tubes. Shades of Ampeg!

-Dave-
 
Last edited:

mavuser

Enlightened Member
Joined
Sep 15, 2010
Messages
8,128
Reaction score
2,636
Location
New York
thanks Dave im kinda mental and typically let any vintage tube amp warm up for about 10-15 minutes in standby. i even have one newer tube amp (Fender Blues Jr Tweed) which has no standby but i let it warm up for a few before I dig in. Thanks!

and yes some Guild amps are the ampeg/fender baby for sure, like the Maverick, but definetly have their own "Guild vibe." The 1963 Guild 98-RT however, which I also own, is a clone of a 1969/1960 Ampeg Reverberocket. loud!
 

mavuser

Enlightened Member
Joined
Sep 15, 2010
Messages
8,128
Reaction score
2,636
Location
New York
i should add that i did let the amp warm up for about 45-50 minutes in standby with the new tubes before plugging in and turning it on. just seemed like a good idea to warm everything up and monitor things. no issues, like i said. the amp was serviced in 2009 and used sparingly to medium since then, not pushed hard, rather "as quietly as possible," new speakers last year, its like a brand new amp now.
 

Default

Super Moderator
Platinum Supporting
Joined
Jul 30, 2007
Messages
13,596
Reaction score
3,008
Location
Philly, or thereabouts
Guild Total
11
Fwiw, standby on later Guild amps just grounds the input signal. B+ still goes through the tubes. The general amp designer consensus is that the standby switch is only there because guitarists expect it to be there. It doesn't save the tubes anymore than turning the volume knob to zero or just shutting it off.
 
Joined
Jul 18, 2016
Messages
1
Reaction score
0
Many thanks to everyone for this forum. Lots of good information and advice here. Just inherited a 2x10 Maverick (lead?) from a friend that I recently helped. It appears to be all original, including the tubes. It also uses 7591's. My friend was using it recently, but I think the 6GW8 tube became too microphonic. Anyway, its mine now and I'd like to go through it before I start using it. Its nice to know that the Maverick is cathode biased. I plan to comb through the previous Maverick discussions to see what do's and dont's I can find. I'm finding pdf schematics for everything but the Maverick lead model. What's up with that? I would like a copy if someone would like to share one. mabarry79@yahoo.com
Sorry that I don't have anything to add right now. I can give updates and post some pics as things progress. Thanks again. -barry
 

mavuser

Enlightened Member
Joined
Sep 15, 2010
Messages
8,128
Reaction score
2,636
Location
New York
Hello Barry welcome to the forum and to Maverick amp ownership. I emailed you that schematic. cheers!
 
Top