|
On Wed, 27 May 2009 23:20:54 -0400, Jon Yaeger <jono_1@bellsouth.net
My recent post about the phasing of OPTs came up because I'm configuring a
tube amp based around the iron from a Sansui 1000A, -- the OPTs are
reputedly made by Tamura or some...
Started by Jon Yaeger on
, 9 posts
by 8 people.
Answer Snippets (Read the full thread at omgili):
OK, but
that 47uF was a lousy value, and should have been and toasting 1/2 an... .
But as soon as the amp moves cathode bias with 2 x 600 ohms plus 2 x 47uF.
Just like with fixed bias or individually bypassed Rk
for each tube.
|
|
Does anyone have any experience or impressions of JWN tube amps?
http://jwnamplifiers.vpweb.com/default.html
Started by JakeJ on
, 4 posts
by 4 people.
Answer Snippets (Read the full thread at audiocircle):
What is PFO? I don....
Each output tube is independently cathode sounding amp.
I current have a quad, and output transformers from a Rowe jukebox (IIRC) .
Makes swapping tubes very easy.
biased, as are all of his amps I believe.
|
|
On Tue, 30 Dec 2008 18:22:15 -0800 (PST), savy <msavoie@ns.sympatico.ca
I have a Push pull Class a/b tube amp (pepco 725 head) with 6v6s that
I'd like to add 2 EL84s (all cathode biased and fed by a split load
phase inverter) as alternates and ...
Started by savy on
, 4 posts
by 2 people.
Answer Snippets (Read the full thread at omgili):
On Tue, 30 Dec 2008 20:46:23 -0800 (PST), savy <msavoie@ns.sympatico.ca
Just have two amps and switch.
__
Steve.
Bother
switching final sections? Just have two amps and switch
between them.
|
Ask your Facebook Friends
|
HEy Folks,
I am asking a question in general. I am wondering about cathode bias systems and the resistor used to bias the output tubes.
As I understand it, if you increase the bias resistor, you also increase the voltage at the cathode. Correct?
I also...
Started by Jcricket on
, 13 posts
by 6 people.
Answer Snippets (Read the full thread at audiokarma):
I am wondering about cathode bias systems in the power supply along ....
It is measureing right at 17 volts: : HEy Folks,
I am asking a question in general .
This is an el84 PP amp.
That has a 1.5k cathode bias resistor.
|
|
Guys, can I use the test points without the scope?
I mean I biased a dozen of amps using kind of Weber bias meter (attached between tube and a socket) + voltage meter and calculated bias from known formulas. And wanted to know if the SVT's test points...
Started by boroman on
, 20 posts
by 7 people.
Answer Snippets (Read the full thread at talkbass):
"Hot" bias runs as a ....
"Cold bias" will make the amp sound a little thin and late to breakup up.
Having life.
MV=mA on the cathodes.
A 1 ohm resistor between cathode and ground.
Circuit as a "Bias King" uses.
|
|
Alreet?
Thinking of taking the plunge into the world of tube amps. I'm looking for around 40W-50W of power, loud enough to gig with a 5 piece anyways. A few other things to take into consideration.
1) Weight: The lighter the better, My arms are shit (...
Started by shmeegle on
, 12 posts
by 8 people.
Answer Snippets (Read the full thread at ultimate-guitar):
True, although (depending on the amp) a head can weigh as much as a 1x12 combo My So Cal 50 weighs a amp and cab to save weight.
I'd get the Classic 30.
All of those amps are great, and would be a massive improvement over an AVT.
|
|
As per Mark, the preamp layout is as follows:
V1 - Input High Gain
V2 - Cathode Follower High Gain
V3 - Cathode Follower Clean
V4 - Input Clean
V5 - Phase Inverter
My current set up is:
V1 - NOS RFT
V2 - Ruby HG+
V3 - Ruby HG+
V4 - GT R3
V5 - Sovtek LPS...
Started by King Guitar on
, 11 posts
by 4 people.
Answer Snippets (Read the full thread at rig-talk):
FL cabs usually project for amps that need a little help other, as opposed to them being ....
You are also going?
The certainly wouldn't be my first choice .
Good tubes, just not for this amp.
ARS/Tesla tubes don't do the amp justice.
|
|
After 10 years having previously replaced all parts (caps resistors), one channel has gone and I thought it was a burned out Cathode resistor 470 ohm 4 watts. When I poked about I also found a blown coupling cap in parallel with the offending resistor...
Started by quadamp on
, 13 posts
by 10 people.
Answer Snippets (Read the full thread at vintage-radio):
I would concur.
With the overheating bias resistor.
|
|
I see alot of different bias probes on ebay,some with a shunt (R) and some with out.What one is the "Best" or easyest for a novice to use.SLP 100RI
Started by bobtec on
, 12 posts
by 5 people.
Answer Snippets (Read the full thread at metroamp):
As for the bias probes with or without the resistor, they are both measuring exactly the same you are measuring combined plate and screen ....
Your killing me Smalls Although the resistor is a shunt, breaking the cathode connection accurate.
|
|
After a long interlude, I decided to clean the wood/metal/uncontrolled coulombs shop and see what's here.
I resurrected my "pretty" Simple SE with the blown diodes, plus the prototype Simple SE (currently set-up for 6v6s or 6BQ6s, the one with the plate...
Started by hareynolds on
, 8 posts
by 4 people.
Answer Snippets (Read the full thread at diyaudio):
How about :
(a)....
If George could offer a 10-line tutorial, I'll be off and running, an adequate cathode bias resistor or other suitable means [I assume this means a FUSE] is required.
A cathode bias to a fixed bias.
|
