Removing tubes on a dual rec for lower wattage

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EMGguitarist

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Hey guys... I've noticed that many of you have mentioned that two tubes can be removed from a dual recto to make it lower wattage so you can get more saturation out of the tubes at lower volumes.... is this possible on my dual rec trem-o-verb combo as well as will it damage the amp? o yea, and which tubes would need to be removed?
 
Yeah, set your TOV to tube rectifier, remove either the outer tube so the two inner tube remains.

Or remove the inner tube so the outer tubes remain.

Your output transformer are now doubled. So your 8 ohm tap is now 16 ohms etc ...

Now someone correct me if I got this all wrong.


You do get some power tube saturation

... But your output transformer remains a "clean" 100 watt transformer. A lot of the cranked up low power tube amp mojo bling, bling comes from the some saturating output transformer. That's why everyone with a 100 watt amp will say: "My amp sounds great, but I have to crank it up to get it to sound great. ... and its too loud."

That is because you are driving the power tubes and output transformer.

So its a matter of taste if it works for you. Personally, I rather play all 100 watts and try something like a power soak.
 
You don't necessarily have to set it to tube rectifier, but you can pull either the two outside or two inside tubes. If you use the tube rectifier instead of diodes, you need to pull one rectifier tube also.

...and yeah, the outputs are doubled. If you have an 8 ohm cab, you want to plug it into the 4 ohm tap. Whatever your cab is, plug it into the one that's half of what the cab is.
 
mikey383 said:
You don't necessarily have to set it to tube rectifier, but you can pull either the two outside or two inside tubes. If you use the tube rectifier instead of diodes, you need to pull one rectifier tube also.

...and yeah, the outputs are doubled. If you have an 8 ohm cab, you want to plug it into the 4 ohm tap. Whatever your cab is, plug it into the one that's half of what the cab is.
Thanks Mikey, I forgot that step. :wink:
 
It will change the charachter of the distortion but do not expect instant bedroom amp. You'll be disappointed if that is your expectation. I liked EL34's and an OD out front at low volume.

If you want a good reference look at Mikey's pics on the road case he built. I noticed he had two tubes pulled.
 
clutch71 said:
It will change the charachter of the distortion but do not expect instant bedroom amp. You'll be disappointed if that is your expectation. I liked EL34's and an OD out front at low volume.

If you want a good reference look at Mikey's pics on the road case he built. I noticed he had two tubes pulled.

This is true. It won't make a practice amp. It's not a significant volume change. You may find that you like the sound of all four tubes rather than just having two. I like the sound of just the two, plus it's cheaper to retube. I can buy a quad of tubes, and that will last me twice as long.
 
Better to use an attenuator. I like the ones that Weber makes. THD also makes good attenuators.
 
try it for sure to see what you like. I pulled 2 tubes out of mine to run at 50w and the amount of extra output I could use was minimal. I actually preferred the slightly bigger/punchier sound of the 100w.
 
Hey,

I tried this trick with a Nomad 45 and it made the amp sing, it is well worth giving it a try.

What I was wondering is can the same be done with amp that have the capasity to reduce the wattage? I now have a Roadster and would like to try it again but am unsure if it could cause damage.

Any tried on a Roadster or Lonestar etc?

Thanks

Gaz
 
garylowe4 said:
Hey,

I tried this trick with a Nomad 45 and it made the amp sing, it is well worth giving it a try.

What I was wondering is can the same be done with amp that have the capasity to reduce the wattage? I now have a Roadster and would like to try it again but am unsure if it could cause damage.

Any tried on a Roadster or Lonestar etc?

Thanks

Gaz

Pulling two tubes on the Roadster would be pretty much the same as flipping the switch to 50W, except for the impedence mis-matching (the tubes are still connected to the OT for impedence purposes).

Dom
 
Hi,

I was thinking, if it on the 50 watt setting would removing the tubes make it 25 watt?

Would this incur any damage?

Thanks

Gaz
 
garylowe4 said:
Hi,

I was thinking, if it on the 50 watt setting would removing the tubes make it 25 watt?

No.

Each tube will dissipate a maximum of approx. 25W. The Roadster is a class AB amp, also known as a push-pull design, and requires tubes to be in pairs to operate correctly. So with that said one pair of tubes is providing 50W, two pairs 100W. When you flip the 100W/50W switch to 50W, you are removing one pair of output tubes from amplifing the signal, reducing the output to 50W.

Dom
 
I took 2 tubes out of my DR and I like it much better. I can get a little more saturation with drowning out everyone else in the band. I know most people play it at 100 watts, but that seems like its for a stadium
 
The key thing to have in mind is that when pulling tubes out, power will be reduced and so will frequency bandwidth - you will lose some bass and some treble. The only way to keep your saturated tube tone (almost) intact and reduce your output is by using a good attenuator.

EDIT:
njsurf said:
I know most people play it at 100 watts, but that seems like its for a stadium

Indeed. One of my good friends claims that anything over 25 watts and 1x12 is compensating :)
 
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