By the way razorrick, I went over to my friends place to show him some of the settups of the pedal I made for him, and he really liked the diode connected mosfets sound. It sounded quite smooth with their body diodes clipping, put a bit of the soft clipping in there too..sweet. His amp is tube preamp, with SS output. The LED/Ge diode works for my setup but there are quite a few other combos that are nice.
yes in theory at least that is the way one would assume would work. but depending on the clip point at first stage,if it is slightly clipped at first stage, then brought to post clip after some filtering..if the post clip is a higher voltage threshhold, it imparts a different sound. That is the staging I hear on it when setup that way. more 3 dimensional sound. I will sketch up something, but it will follow the same sort of ideas as I described.
ok good, thank you, i just need to get the eb91, as for the rest of the pedal we said make it all tube right? well i've decided to go the whole way with a 12at7 PP output. might make teting a bit easier too. a chasis has already been drilled out, ive got a transformer with a HT of about 220v, but ive got a 12-240 im considering putting in a more stompbox package at the end of it.
Nice, you could probably get a sweet 1 watt out of it. That would be great on a ''pedal'', because most tube based pedals are only preamp type distortion. This way, you get the whole amp distortion and can use it as a practice amp, or run the output through an attenuator into a bigger amp. . The 12 AT7 could also be paralleled with a common tail and run class A SE.
From what ive tried before, it peaks at about 2 watts in PP, i did try a parallel SE with 12AU7s but there was alot more hum, i would try it again though. and you probably wouldnt need alot of attenuation, at full output you only get about 3v at 4 ohms, so maybe -6dB would be fine into a 4 ohm dummy load.ive still got a 12k5 12v power tube i may try for low voltage power tube distortion, but thats another project.
I was thinking more a 12VAC wall wart with a 12-240 v transformer, though i have been meaning to try out a flyback converter in something. I havn't found too much difference between a 12AT7 and AU7 in the output position, bias may be sligtly different. With a DC multiplier i think it should definatelly be push pull, could introduce some nasty harmonics in SE if it isnt filtered properly, which would probably end up fairly inefficient.
Good to see you boys still working out new ways to mess up guitar signals!
See what triodes do operating with some positive voltage on the grid to give some acceleration to electrons coming off the cathode, with the anode voltage low. As the grid is very close to the cathode, a comparatively small positive voltage on it will give the same sort of field strength that a much higher voltage on the anode would....
With grid current flowing the impedance looking into the grid will be lower than normal, so drive requirements will be higher, but it will be a non-linear impedance - more distortion so long as you don't feed it too well ...
See what triodes do operating with some positive voltage on the grid to give some acceleration to electrons coming off the cathode, with the anode voltage low. As the grid is very close to the cathode, a comparatively small positive voltage on it will give the same sort of field strength that a much higher voltage on the anode would....
With grid current flowing the impedance looking into the grid will be lower than normal, so drive requirements will be higher, but it will be a non-linear impedance - more distortion so long as you don't feed it too well ...
Yes Simon I think this ought to be fun . Razorrick has some good ideas going.
Right now I have my parts in to do a smallish 5 watt SE. There are a few things I plan to do on the preamp V1 and V2 stages regarding their biasing ''arrangements''. The tube diode pair will be setup between pre and output stages. Normal output SE saturation imparts a different sound than AB operating Push Pull, and I want to bridge the gap so to speak with the diode setup, and see what happens. Tube diodes will be interesting. More glowing stuff is always nice too.
Right now I have my parts in to do a smallish 5 watt SE. There are a few things I plan to do on the preamp V1 and V2 stages regarding their biasing ''arrangements''. The tube diode pair will be setup between pre and output stages. Normal output SE saturation imparts a different sound than AB operating Push Pull, and I want to bridge the gap so to speak with the diode setup, and see what happens. Tube diodes will be interesting. More glowing stuff is always nice too.
You'd have to make sure that the neon never went out - extinction and striking make nasty transients, sound really bad - but who knows you might even like that!
and to be honest, ive blended a few nasty effects to get some decent sounds, mainly diode distortion with all out fuzz touched into a normal overdrive, a parrallel effect box can give so much more possibility than just running through some pedals.Razorrick, I know we said ''all tube'', guess a neon could be considered a tube! Ok I may use a couple of elements not tube, but not in the signal path. Just for DC stabilized biasing and power supply rectification purposes.
I built an optical fuzz once. IR emitter and IR photodarlington It was interesting but kind of a one trick pony.
I built an optical fuzz once. IR emitter and IR photodarlington It was interesting but kind of a one trick pony.
well, i wouldnt exactly class a neon as solid state! I agree SS rectification would be best, expcially seeing as its not really an exceptionally high voltage idea, I might leave the diode biasing for this, I like it for Music, not so much for guitar, i prefer to have the high/mid boost.
That sounds interesting, one trick pony as in it was fuzz or no fuzz?
That sounds interesting, one trick pony as in it was fuzz or no fuzz?
Yeah, you could vary the fuzz level a bit but the photodarlington squares up really fast. One thing that was cool, was there isn't a lot of associated noise coming from a high gain audio stage clipping. Very synthesizer like sound. Suppose you could add some filtering, integration circuits and such to get into Moog style.
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