#1
i read that if you take two tubes out of the power amp of a 100 watt head, it would take it down to 50 watts... is this true? i thought the amp wouldnt work without all the tubes plugged in. if it is, would it be possible to take the tubes out, and put them in as you need the power?
#3
i dont think it would work either, but theres prolly a mod where u finish the circuit, cuz if u dont then no power will b able 2 get thru. if u want, get a 50 watt amp??? or get a pro 2 mod it 4 u.
#4
Quote by freedumb
i read that if you take two tubes out of the power amp of a 100 watt head, it would take it down to 50 watts... is this true? i thought the amp wouldnt work without all the tubes plugged in. if it is, would it be possible to take the tubes out, and put them in as you need the power?



this works and works well. how ever not all amps can do this little trick, it depends on how the tubes are connected ( series or parallel)
but for the most part nearly all common 100w amps will pull this off.
only pull either, the two inner OR the two outer power tubes (that one is important)


the second part to this though, you have to change the impedance setting on the head, because you are only using half of the tubes, the loading on the output transformer changes, IIRC you need to set the impedance to half of your cabs value.

more can be found here on this topic
http://www.amptone.com/pullingtubes.htm
Last edited by slidecontrol at Jun 9, 2006,
#6
^Depends on the amp.

It's not really reccomended though, as it pulls less current from the rest of the power supply of course, which can affect the other tubes. I can do it with my homemade Fender, but I don't because it makes the tubes bias too hot. And I have an attenuator, so there's not much of a reason anyways
I'm not very active here on UG currently.
I'm a retired Supermod off to the greener pastures of the real world.
#7
Can you do that with a 50w head?

You can only pull out a pair of tubes on amps that have 4 power tubes. Most 50W amps will only have 2 tubes in the power section, and you can't run the amp on a single tube.
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