what's your opinion on half power switch? tone drain?should I mod an amp for it?

Started by everdrone, June 14, 2012, 01:36:36 AM

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everdrone

what's your opinion on half power switch? tone drain?should I mod an amp for it? prolly expensive mod. I have one on my Marshall JCM900 4500, not too bad. it definitely changes the characteristic of the tone since it takes out some more of the bass by default.  does the half power switch sound good on other amps like the new Orange th100, Mesa Boogie Rectifier and Roadster, Tiny Terror, and countless others?  is it worth buying an awesome 100 watt amp like an Ampeg V4 even though I could buy an Ampeg V2, and then add a half power switch?  is that like "having two amps" like the ads read?  one for practice and turn switch to full power for gigs?  People say to just pull tubes but on other forums amp techs and gurus say dont just pull tubes as it hurts your amp.  I dunno, prolly the purist thing is to just buy one amp for each needed use, a 50 watter for practice and a 100 watter for shows?  some say a half power switch add on is expensive and sucks out the lows and does a weird EQ curve to the high frequencies  ??? ??? ???

Mr. Foxen

There is probably a dozen or more ways to implement a half power switch, all depends which one is used.

everdrone

thanks brutha, I did not realize that until you said it, now I see it is pretty clear :)


I will prolly get an Orange tiny terror combo in the next 12 months or so, the 7 to 15 watt switch does not require switching the ohms to the cabinet, right?

I definitely would only want to change the headroom so that I hear the amp's distortion at a lower volume.  I think I would want to do this through a switch that pulls out two tubes basically, but I am not sure how that alters the tone since the amp was designed for full volume pure tone, and a lesser wattage amp is designed for just that.  i.e. I dont think an amp designer of a 100 watter amp and a 50 watter amp would say that the 100 watter sounds just the same as a 50 watter if you pull two tubes and use a different ohm to go to the speakers.

those v2/v4s sound great, I have been a fan of QOSTA/kyuss for years as my top 5 fav band, Josh digs those and they sound great on his albums.

http://www.drtube.com/schematics/marshall/jcm900.pdf is my amps schematic which says

8. Output Mode Switch
Switches the amplifier from high to low power
output. The "low" setting configures the output
stage to "triode" operation, which gives half the
rated output (i.e. 25 Watts on 50 Watts models - or
50 Watts on 100 Watt models). The "high" power
position gives "pentode" operation for the full
rated output.

this does not mean I need to switch the ohms, right?  for some switches When in half power you really need to change the speaker from the 8 to the 4 ohm output because taking a pair of tubes offline effectly doubles the ohm rating.  I dont think this is the case here cause it really is pentode/triode changing the way the tubes work, right? 

people say slightly more mids and a slightly more compressed feeling in triode mode. It really chops off the top and bottom and leaves nothing but mids...


there is like 10 different types of switches.  I am skeptical about the hotplate attenuator types - I remember some people fry their amps doing that cranked volume route.   like a tweed switch which drops the voltage going to the power tubes, this will alter the tone.

clockwork green

Use fewer and more inefficient speakers instead. Why do you need really need a quieter amp? A cranked 50-watt amp isn't going to be much quieter than a 100, just less headroom and the lows won't have the same impact. If you need a quieter amp and a louder amp then buy a 100-watter and then a smaller 5-10 watt practice amp. It'll work better than a mod or a half power switch which always seems to neuter the tone.
"there's too many blanks in your analogies"


fallen

Good answer. I use an attenuator at home and it's a godsend. Perfect for what you describe. Use your regular amp at normal settings and just knock it down a few dB for practice.

Mr. Foxen

Or do what I do and buy the house, and tell everyone else there to like it.

clockwork green

Or do what I did and have your girlfriend by the house and make sure it includes a detached studio in the garage :)
"there's too many blanks in your analogies"

dunwichamps

pentode triode mode switches wont change OT output taps. I like the Weber attenuators a lot. The only great way to handle power is to design it into the amp

Stonergrunge

mmmm that is probably the main reason of why I'm not willing to buy a tube amp, the loudness issue, the inconvenience of not being able to use it at bedroom levels and ending up with a very big and expensive adornment. I've been using a 30w solid state amp for 13 years, don't have a band so I don't see the point of buying a new one, although I've seen a couple of amps that apparently are awesome in terms of features (2 channels, 3-band eq, reverb, 12" speaker(s), fx loop) but right now there's no reason to say "shut up and take my money!".

Maybe if I had a band things would be different, but spending money on a 15w or lower tube amp seems unreasonable when facing up to the question of "what if I finally start playing in a band but the small tube amp can't keep a clean sound during rehearsals?".

So in the end, the result is always the same: I buy nothing and keep using my ss amp.
cartoons, chocolate milk & rock 'n' roll!!
Fuzz is love

everdrone

thanks yall, great feedback.  I figure ampeg v4 would be insanely loud for an average joe like me, I like the low end tho, still mulling this over, I see yall have had success with the attenuators, I was worried about them harming amps but a lot of amp companies make attenuators