Where did those pics come from DrNomis ?DrNomis wrote:Just to put things into perspective,here are some screenshots of what "real" tube/valve distortion really looks like....
culturejam wrote: We are equal opportunity exposure artists.
Greg_G wrote:Where did those pics come from DrNomis ?DrNomis wrote:Just to put things into perspective,here are some screenshots of what "real" tube/valve distortion really looks like....
The 12AX7 ones look a bit strange.. very non-symmetrical, and the sloped lines on the upper part of the trace looks like they're being affected by the protection capacitor in the scope.
culturejam wrote: We are equal opportunity exposure artists.
Greg_G wrote:OK.. but the Baja Real Tube is a starved plate design isn't it ?
If so, I don't think it's really indicative of an amp design/clipping.
I think the sloping lines are from a capacitor charging.
I can't really see how phase shift would cause that... it's a change in output level during the clipped periodDrNomis wrote: The sloping lines could also be caused by phase-shift effects at low frequencies too....
culturejam wrote: We are equal opportunity exposure artists.
Greg_G wrote:I can't really see how phase shift would cause that... it's a change in output level during the clipped periodDrNomis wrote: The sloping lines could also be caused by phase-shift effects at low frequencies too....
... and you're using a pure 1KHz sinewave anyway.
I wasn't knocking DrNomis.. just discussing..DrNomis wrote:Anyway,what you see in the pics are the results I got with what I had access to,I thought that it would be a good idea to post the pics here so that we could do comparisons.....
Other people may get similar or different results with the equipment they have access to,and they're welcome to post screenshots here if they like....
culturejam wrote: We are equal opportunity exposure artists.
Greg_G wrote:I wasn't knocking DrNomis.. just discussing..DrNomis wrote:Anyway,what you see in the pics are the results I got with what I had access to,I thought that it would be a good idea to post the pics here so that we could do comparisons.....
Other people may get similar or different results with the equipment they have access to,and they're welcome to post screenshots here if they like....
If you're gonna design something and aim at a waveform, it's pretty important to start with the right waveform to shoot for.
I tried to find some pics with a web search and didn't have a lot of luck, but I did find a couple of an AC30.
I hope the owner doesn't mind me borrowing them.
I agree.DrNomis wrote: No worries mate, discussion is good, that's how people can learn from each other....
Believe it or not,it is actualy very hard to get a good distortion sound out of a tube amp, alot of work needs to go into it, it is easy to add gain but very hard to get it sounding good, and I have alot of respect for designers who can successfully get good sounds,eg Peavey (their 5150 series Amps), Marshall, Vox, Soldano, etc....
culturejam wrote: We are equal opportunity exposure artists.
Greg_G wrote:I agree.DrNomis wrote: No worries mate, discussion is good, that's how people can learn from each other....
Believe it or not,it is actualy very hard to get a good distortion sound out of a tube amp, alot of work needs to go into it, it is easy to add gain but very hard to get it sounding good, and I have alot of respect for designers who can successfully get good sounds,eg Peavey (their 5150 series Amps), Marshall, Vox, Soldano, etc....
There are some great sounding Boutique amps around.. but I guess they're more a refinement and tuning of a previous circuit.
A lot like the world of effects..
true, very true. Τhis is an answer to those who credit tubes with divine qualities. The design makes the good sound, not the tube itself.DrNomis wrote: Believe it or not,it is actualy very hard to get a good distortion sound out of a tube amp, alot of work needs to go into it, it is easy to add gain but very hard to get it sounding good, and I have alot of respect for designers who can successfully get good sounds,eg Peavey (their 5150 series Amps), Marshall, Vox, Soldano, etc....
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billonious wrote:true, very true. Τhis is an answer to those who credit tubes with divine qualities. The design makes the good sound, not the tube itself.DrNomis wrote: Believe it or not,it is actualy very hard to get a good distortion sound out of a tube amp, alot of work needs to go into it, it is easy to add gain but very hard to get it sounding good, and I have alot of respect for designers who can successfully get good sounds,eg Peavey (their 5150 series Amps), Marshall, Vox, Soldano, etc....
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blackbunny wrote:At the risk of being a smartarse, after following the progress of this topic it's apparent that there are lots of possible tones / waveforms when trying to produce 'tubelike' ('valvelike' for Aussies & Brits) overdrives and distortions.
Just take the difference between symmetrical and non-symmetrical clipping. There you have a major stompbox milestone, encapsulated neatly back in the mid 70's: the Maxon / TS symmetrical clipping versus the very similar Boss OD-1 with asymmetrical clipping.
Since most tube / valve output stages tend to clip fairly symmetrically if they're biased properly and the tubes / valves are reasonably well matched, and they tend to emphasize even-order harmonics which make a smooth sounding distortion, the magic distortion ingredient in the 60's was the transistor fuzz, which could produce spiky, asymmetrical waveforms loaded with (harsh sounding) odd-order harmonics. Plug a nasty fuzz into a smooth-sounding valve amp and PRESTO! Magic!
IMO, the 70's stompbox revolution was launched by the difference between symmetrical and non-symmetrical clipping, conveniently (and cheaply) created by diodes, and we're still exploring the possibilities over 30 years later.
