PeeMonkey Posted July 8, 2004 Share Posted July 8, 2004 Ive seen these for sale and was wondering do these work good with tube amps, it basically just goes into effects loop so you crank up the volume or something on the amp and you lower it through this box, its supposed to get the tubes working at high volumes but with low output. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=38074&item=3734340774&rd=1 Heres a link for one on ebay Link to comment Share on other sites More sharing options...
SuperFreak Posted July 8, 2004 Share Posted July 8, 2004 No Master Volume? Then you MUST have one of these I had a similar homebuilt sort of thing between a 100w Randall Head and a quad...crank to 10 and feel the HEAT! (It was based loosely on EVH's 'light dimmer switch' contraption that a friend who was electronicly inclined tossed together with old bits and pieces) And @ $20 ...why the hell not give it a try! How can we fight ignorance and apathy? Who knows! Who cares! Link to comment Share on other sites More sharing options...
J J Posted July 8, 2004 Share Posted July 8, 2004 yea i stumbled upon those too i wonder if it's bad for the amp if it's being pushed that much... that would be my biggest concern but yea, 20$ isnt bad at all, i'll try it when i feel like it (trying to hold back on GAS) Link to comment Share on other sites More sharing options...
Guitarzan Posted July 8, 2004 Share Posted July 8, 2004 give Myles a shout, he will tell you strait what this will do. http://www.soundclick.com/bands/pagemusic.cfm?bandID=193274 rock it, i will Link to comment Share on other sites More sharing options...
Major Tom Posted July 9, 2004 Share Posted July 9, 2004 When you put a volume control into the effects loop, it does exactly what a master volume on an amp does - it cuts the amount of signal going to the power tube section. This guy's ad isn't quite as exaggerated and misleading as another ebay vendor's that made me want to puke when I read it. They give the impression that it will allow you to get cranked power tube distortion ( I think the other guy's might have even come out and said that) at low volumes. Some even get the impression that it does the same thing as a "load dump" attenuator like a THD Hotplate, or Dr. Z Airbrake. It absolutely will not do that, it does what a master does, reducing the signal level to the power section so the preamp can be set for more distortion at low volumes. It won't hurt the amp though, and may be useful for an amp that doesn't have one, or for a master on the clean channel of an amp that doesn't have a master. Anyway, neither one state that it would be completely redundant for an amp that already has a master volume, and it is... IMHO it should be presented as a master volume for amps that don't have one. Link to comment Share on other sites More sharing options...
Gabriel E. Posted July 9, 2004 Share Posted July 9, 2004 Major Tom's right. It's just a master volume control. It will allow you to crank the preamp gain without increasing the overall volume of the amp. A big part of the "cranked tube amp tone" comes from the POWER tubes being pushed to distortion. This device will do exactly the opposite of that. Need a speaker attenuator to allow you to crank up the whole amp without killing your eardrums. "You never can vouch for your own consciousness." - Norman Mailer Link to comment Share on other sites More sharing options...
Werewolf by Night Posted July 9, 2004 Share Posted July 9, 2004 Yuhp. What Major Tom said. Pointless if your amp already has a pre-gain/volume and a master-volume kinda set-up. Unless you have troubles with too hot of a return on your effects-loop, in which case it would work as a distortion reducer... It works better to have a "master volume" after the driver-network, i.e. the "phase-inverter" tube and circuit. Most are before it, though, I believe. The effects-loop sure is. Funny thing is, many tube-amps that don't have a master volume, also don't have an effects-loop or similar I/O on 'em, anyways! Ask yourself- What Would Ren and Stimpy Do? ~ Caevan James-Michael Miller-O'Shite ~ _ ___ _ Leprechaun, Esquire _ ___ _ Link to comment Share on other sites More sharing options...
Major Tom Posted July 9, 2004 Share Posted July 9, 2004 It works better to have a "master volume" after the driver-network, i.e. the "phase-inverter" tube and circuit. Most are before it, though, I believe. The effects-loop sure is. Funny thing is, many tube-amps that don't have a master volume, also don't have an effects-loop or similar I/O on 'em, anyways! I have looked at quite a few amp schematics over the last year or so, most masters are before the phase inverter - I don't think I have seen an after-P.I. master scheme yet, although I have heard of them. I know that the concept of marketing a product dictates to exaggerate its strengths, but these ads are downright purposely misleading. Link to comment Share on other sites More sharing options...
Blue Strat Posted July 9, 2004 Share Posted July 9, 2004 Originally posted by Caevan O'Shite: It works better to have a "master volume" after the driver-network, i.e. the "phase-inverter" tube and circuit. Most are before it, though, I believe. The effects-loop sure is. Funny thing is, many tube-amps that don't have a master volume, also don't have an effects-loop or similar I/O on 'em, anyways!Ok, buddy. I got to call you on that one. Does a JCM 800 2204 sound bad? I think not, and it's got the master volume before the phase inverter. In my own experiments, I've found that the pre-phase inverter master volumes sound better to my ears. The post PI master volumes are best when the coupling caps are small and a dual pot is used instead of the Matchless style MV (one pot wired as a variable resistor between the two out-of-phase outputs of the phase inverter). The Matchless master volume works through phase cancellation, which assumes that both outputs of the PI are identical, only 180 degrees out of phase with each other. BlueStrat a.k.a. "El Guapo" ...Better fuzz through science... http://geocities.com/teleman28056/index.html Link to comment Share on other sites More sharing options...
Werewolf by Night Posted July 10, 2004 Share Posted July 10, 2004 O.K.! Come to think of it, I guess that a Matchless might be the only amp that I know for sure had that set-up (master-volume AFTER the "Phase-Inverter"). But I still think it's funny that most of the amps that have effects loops or similar I/O out back probably wouldn't gain anything by sticking someting like that in there. (Most amps w/ fx-loops already have a master-volume design, and the loop is usually still iserted before the P/I.) You could always try any pedal that you might have lying around that has a volume control on it in the loop, for an idea of how it might sound... (To simulate the effect of a "Gain Control"-gizmo.) Ask yourself- What Would Ren and Stimpy Do? ~ Caevan James-Michael Miller-O'Shite ~ _ ___ _ Leprechaun, Esquire _ ___ _ Link to comment Share on other sites More sharing options...
Guitarzan Posted July 10, 2004 Share Posted July 10, 2004 ???????? (makes doglike sideways headcocking motion)..i am dumb http://www.soundclick.com/bands/pagemusic.cfm?bandID=193274 rock it, i will Link to comment Share on other sites More sharing options...
Blue Strat Posted July 10, 2004 Share Posted July 10, 2004 Some amps aren't going to have enough gain in the preamp section to go into clipping. Overdrive is produced by clipping off the tops of the sinewave like guitar signal. This happens when the signal is increased in amplitude until the extreme swing of the signal is hitting the supply rails. When a tube or transistor is wired in a circuit, the control element (the input) is held as a certain voltage. For the least distortion of the signal, you'd want the input held at half of the supply voltage. (4.5V for a 9V supply) Lets say that your input signal is 10V, from the top peak to the bottom peak. Some clipping will occur, about 0.5V on each side. A post PI master volume takes advantage of the preamp gain overdriving the PI. The last stage of the preamp might remain clean and still cause clipping in the phase inverter. With the master volume before the PI, you're limiting the voltage swing of the signal, and you're not going to overdrive the PI unless the master volume is wide open. BlueStrat a.k.a. "El Guapo" ...Better fuzz through science... http://geocities.com/teleman28056/index.html Link to comment Share on other sites More sharing options...
Werewolf by Night Posted July 10, 2004 Share Posted July 10, 2004 Originally posted by Guitarzan: ???????? (makes doglike sideways headcocking motion)..i am dumb Firstly... No, you're not! Secondly... What izzitt you're not sure of here, 'zan? Ask yourself- What Would Ren and Stimpy Do? ~ Caevan James-Michael Miller-O'Shite ~ _ ___ _ Leprechaun, Esquire _ ___ _ Link to comment Share on other sites More sharing options...
Guitarzan Posted July 11, 2004 Share Posted July 11, 2004 i am only stupid about the actual technical discusion about the phase inverter stage etc. nothing serious dude. i haven't dove into the finer points of the inner workings of tube amps. i am ok with my ignorance. just being funny in my own way Caevan. http://www.soundclick.com/bands/pagemusic.cfm?bandID=193274 rock it, i will Link to comment Share on other sites More sharing options...
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