It is currently Mon Mar 16, 2020 4:53 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 39 posts ]  Go to page Previous  1, 2, 3
Go to page Previous  1, 2, 3
Author Message
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Thu Nov 07, 2013 10:02 pm
Offline
Professional Musician
Professional Musician

Joined: Fri Jun 26, 2009 6:53 pm
Posts: 2252
Location: Harvard IL
Yep Yep, All is cool!!! Keep up the good work!!!

_________________
None of Us are free, if One of Us is chained !


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Fri Nov 15, 2013 11:24 am
Offline
Roadie
Roadie

Joined: Sat Mar 09, 2013 12:27 pm
Posts: 207
I had a friend in college who was one of the best guitarists I've ever known. He had a late 60's tele and a blackface deluxe reverb-great sounding and frickin' loud. He'd dime the controls and beat the heck out of it. When he traveled he'd take the neck off his tele, fold it in half, with the strings on it, and stick it in his backpack. One of the power tubes blew up in his deluxe. He pickup up a pair of 6V6's at an electronics store, stuck them in and turned the bias pot until he got the sound he wanted. It sounded great. The point is that sound matters more than numbers.


Top
Profile
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Fri Nov 15, 2013 6:57 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Krankster wrote:
...The point is that sound matters more than numbers.


The two are not mutually exclusive, and that is the point that many seem to miss. If the numbers aren't correct, the sound might not last. People are often quick to dismiss things that they don't understand. :wink:

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Wed Nov 20, 2013 11:27 am
Offline
Roadie
Roadie

Joined: Sat Mar 09, 2013 12:27 pm
Posts: 207
aclempoppi wrote:
I don't subscribe to the 70% number. Don't know if a guru came down off the mountain and delivered that number??? But I do know an old tech and electronic engineer, told me to set my RCA's(6L6GC) at about 28ma draw, and forget about it!!! I mean, forget about it for years!! Have always gone with his advice. The amps have been healthy and the sound is plenty thick and dynamic. JMO, Art


Exactly my point. Most amps that are the same model and manufacturer are going to have similar plate voltages. For example, Fender blackface 40 watt amps are in the 440 ballpark. BTW, when I said there are many ways to measure plate voltage, I was referring to all of the Bias Rite" gadgets available as well as the trusty $15 multimeter. IMO, lots of tubes sound best in the 55% dissipation range. Two of which are the GT6L6GE and the Tung-Sol 6L6GCstr as well as many NOS 6L6's. I measure plate voltage, set the bias, then play it. I've experimented with bias settings on all of my amps and found the sweet spot one each amp by ear. I've remeasured plate voltage after setting the current draw, but it was never enough to change anything. I run 6V6GT's around 70%. I like the sound of them biased hot.


Top
Profile
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Wed Nov 20, 2013 9:27 pm
Offline
Roadie
Roadie

Joined: Sat Mar 09, 2013 12:27 pm
Posts: 207
IIUC, he did have an amp tech do the job, and he listened while the tech "adjusted" between 36 and 35. > "My tech, who has 40 years of experience with professional musicians, lets his customers play the amp before he signs off on it." If it was done by a tech, my guess, the tech did nothing at that point, saw the initial reading go from 36 to 35 (normal with new tubes), and asked; "How does it sound now?", and the OP thought he heard a difference. I have done this myself, set it where it should be set and if they think it isn't quite right, pretend to adjust and ask; "How about that?". It's not surprising how many people notice a difference when nothing at all was done. :wink:[/quote][/quote]

Actually, I set the bias on my amp, as I have for years, and found the setting I liked. My friend who is an amp tech let's his customers play the amps, if they wish, before he gets paid. He's a knowlegable tech who would not rip someone off by or mislead them.


Top
Profile
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Tue Nov 26, 2013 9:54 pm
Offline
Roadie
Roadie

Joined: Sat Mar 09, 2013 12:27 pm
Posts: 207
I picked up another early 70's Super Reverb. Pots dated 72'. Some idiot tried to blackface it-another basket case bought for $250. Love it. The guy had Sovtek 6L6's biased around 70%-47ma with Pv 464. Spent the last week putting her back into shape, Jupiter caps, Sprague atom ecaps, carbon comp resistors and stock bias balance circuit. I had to replace the bias resistor, so I started around 55% + at 36ma. It was ok, but lacked the warm breakup. Finally, installed a 14.94K bias resistor, as close to spec as I had. It biased at 34.6ma. Sounds great-breakups up nicely, warm clean tones. I stand by my opinion that 1.5 ma change can make a difference in tone. Open your ears. Love you guys. Have a great Thanksgiving. Chris


Top
Profile
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Tue Nov 26, 2013 11:57 pm
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
Krankster,

So the amp sounds better at 34.6mA than 36mA at 464VDC on the plates?


Thanks!


Top
Profile
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Wed Nov 27, 2013 3:05 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Yeah, that extra half-watt just kills the tone. :lol: It is understandable, considering that the Plate voltage didn't change even one volt with a change of over 12 mA in current. Amazing! :roll: And, as we all know, a cooler bias gives a warmer tone. :shock: (yes, it was hard for me to type all of that without cracking-up)

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: How do you like your tubes biased-Hot or Cold?
Posted: Wed Nov 27, 2013 8:02 pm
Offline
Professional Musician
Professional Musician

Joined: Fri Jun 26, 2009 6:53 pm
Posts: 2252
Location: Harvard IL
Lighten up shimmy. :) Chris didn't mention the plate voltage on the rehab. Nor, which tubes were used. But yeah, I do run my RCA BP's(Band Master) a bit on the low side. Not after power, just... tone, dynamics, and longevity. Now, I do run the NOS Tung Sol 5881's hotter in the Bassman(2X10 combo). But that's a, Keith Richards, type of rock&roller amp. The RCA 6V6GT's in the Princeton Reverb clone are right about...21ma@418volts. Haven't messed with the first two amps for awhile, so I don't have the specific numbers. Keep Pickin' and enjoy the holidays!!! Art :lol:

_________________
None of Us are free, if One of Us is chained !


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 39 posts ]  Go to page Previous  1, 2, 3
Go to page Previous  1, 2, 3

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: