S
Soupy1957
New member
I've been watching a video on Youtube, in which the presenter/creator was demonstrating Tube replacement in a V3112 Crate Amp.
I asked the question, and made note of the fact that in most Tube Amps, there is a need to check and possibly adjust the Bias when doing a Tube change. The response I got was that "there is a guy in Rig Talk" who says that's not the case.
I will quote from a link here, that begs the question further:
".....tubes vary from sample to sample. Just applying a given bias voltage to a tube is ok. If it's adjusted, the tube will idle properly (and work properly). But if you change your tube or tubes, how do you know they'll bias properly without adjusting the bias? The new tube might be different in bias requirement.
It would be great if tubes were rated by their individual bias voltage. Actually, most companies that sell 'matched' tubes usually print the bias current the tube operates at, right on the box. Unfortunately, each company has their own standards for measuring bias. Plate voltages, plate currents, and other parameters are different from one dealer to another. So they may or may not be interchangeable."
-http://tubedepot.com/whisbipo.html
So maybe that "guy" who said that will read this, and be willing to answer the following:
A) Do you EVER need to check/adjust the Bias on a
V3112 (or ANY "Tube Amp" for that matter)?
B) What are the conditions in which a Bias check/adjustment
would be necessary or prudent?
C) How often is "prudent" for changing Tubes in a "he plays
for about an hour, every other day" situation?
D) Since most Tubes are Russian-made, these days, are
there any that are really better than others? (Mullard's vs
JJ's for example)
E) How can I tell if my Tubes are failing and NEED replacement?
Those are fair (admittedly fundamental) questions, all. Please take a moment (mystery "guy") and respond.
Respectfully submitted,
-Soupy1957
I asked the question, and made note of the fact that in most Tube Amps, there is a need to check and possibly adjust the Bias when doing a Tube change. The response I got was that "there is a guy in Rig Talk" who says that's not the case.
I will quote from a link here, that begs the question further:
".....tubes vary from sample to sample. Just applying a given bias voltage to a tube is ok. If it's adjusted, the tube will idle properly (and work properly). But if you change your tube or tubes, how do you know they'll bias properly without adjusting the bias? The new tube might be different in bias requirement.
It would be great if tubes were rated by their individual bias voltage. Actually, most companies that sell 'matched' tubes usually print the bias current the tube operates at, right on the box. Unfortunately, each company has their own standards for measuring bias. Plate voltages, plate currents, and other parameters are different from one dealer to another. So they may or may not be interchangeable."
-http://tubedepot.com/whisbipo.html
So maybe that "guy" who said that will read this, and be willing to answer the following:
A) Do you EVER need to check/adjust the Bias on a
V3112 (or ANY "Tube Amp" for that matter)?
B) What are the conditions in which a Bias check/adjustment
would be necessary or prudent?
C) How often is "prudent" for changing Tubes in a "he plays
for about an hour, every other day" situation?
D) Since most Tubes are Russian-made, these days, are
there any that are really better than others? (Mullard's vs
JJ's for example)
E) How can I tell if my Tubes are failing and NEED replacement?
Those are fair (admittedly fundamental) questions, all. Please take a moment (mystery "guy") and respond.
Respectfully submitted,
-Soupy1957