you have trouble reading? or comprehending?
I worded it the way I did to convey the fact that nobody seemed sure if the 10K resistor was done on purpose or on accident. As this was research done some years ago, details may not be precise, but I seem to recall it appeared on a particular model and not other models, leading them to conclude it was probably a mistake. I only mentioned it as an example, which fact I thought I had made crystal clear. The fact (FACT) that a lot of discoveries are accidents and that there was a dearth of innovation was the point. Apparently you chose to read it into it something I never said nor intended, and you then responded with an undue degree of pomposity and rudeness. At least get your facts straight first. If you can prove it was on purpose that would at least make you look less offensive
I already made it crystal clear that I do create an amp that distorts. In fact, I even divulged HOW. but you apparently missed that.
if you want me to embrace crappy sounding drivers whose inspiration dates back to the thirties, not happening. it makes MUCH more sense to tailor the frequency response in a purposeful fashion than to buy and discard drivers until you find the one that accidentally seems least offensive.
I didn't ask for your pomposity, save it for your wife.
I worded it the way I did to convey the fact that nobody seemed sure if the 10K resistor was done on purpose or on accident. As this was research done some years ago, details may not be precise, but I seem to recall it appeared on a particular model and not other models, leading them to conclude it was probably a mistake. I only mentioned it as an example, which fact I thought I had made crystal clear. The fact (FACT) that a lot of discoveries are accidents and that there was a dearth of innovation was the point. Apparently you chose to read it into it something I never said nor intended, and you then responded with an undue degree of pomposity and rudeness. At least get your facts straight first. If you can prove it was on purpose that would at least make you look less offensive
I already made it crystal clear that I do create an amp that distorts. In fact, I even divulged HOW. but you apparently missed that.
if you want me to embrace crappy sounding drivers whose inspiration dates back to the thirties, not happening. it makes MUCH more sense to tailor the frequency response in a purposeful fashion than to buy and discard drivers until you find the one that accidentally seems least offensive.
I didn't ask for your pomposity, save it for your wife.
This works quite well with electro-acoustic guitars (as I'm sure you know). One of my friends is now using an Electro Voice powered monitor (ZLX12P) as his (electro-acoustic) guitar amp cum vocal P.A.
True electric guitars are a whole 'nother kettle of fish, of course.
-Gnobuddy
Jerry - please get professional help, soon. You may not realize that you need it, but you really, really do.
Best regards,
-Gnobuddy
Are you using the same +300V node to power all three triodes? If so, yes, you are very likely to run into instability issues related to coupling through the B+ rail.
That should do the trick. Make sure the RC time constant in your B+ filter is big enough to do some real filtering. 120 Hz (full-wave rectified 60 Hz) has a period of about 8.3 mS, so make your RC time constant is at least 10 times bigger than that, which will get you roughly 20 dB of ripple and noise reduction.
If you use modern capacitor values - say, a 270uF, 330 V electrolytic cap salvaged from a disposable camera flash - then it's quite easy to get a nice big time-constant.
-Gnobuddy
I agree. Every once in a while, the wheels of technology move in one direction, and quite unexpectedly, there is an accidental benefit somewhere else. In this case, capacitors developed for flash cameras turn out to be wonderful things for re-designs of ancient valve-based electronic circuits.
I recently began to see several mirofarad-sized ceramic caps at Mouser.com, at reasonable prices. I have begun to use them as cathode bypass caps in valve designs. They have tighter manufacturing tolerances than electrolytic capacitors, and no liquid electrolyte to dry out over time. Voltage ratings are quite sufficient for cathode bypass caps on most commonly used preamp valves.
The optimum value to use depends both on the transconductance (gm) of the valve in question, and the desired -3dB lower cutoff frequency. I'm using values up to 10 uF with some higher-transconductance preamp valves.
-Gnobuddy
I did too until I had one catch fire on a particularly hot day several decades ago. They're not rated for continuously applied DC in most cases, and this one was used at 15% below rated voltage and with zero ripple current involved. (The cap was purchased new and lasted about nine months in the application.)
Putting it out involved the use of a dry agent fire extinguisher and the resulting mess took a few hours to clean up.
I talked to a bunch of other hobbyists/techs at the time and it turned out that my experience was not too uncommon.
Needless to say I have not used them since, and recalled a bunch of stuff I had modified using photo flash caps to replace them (at my expense) with something safer.
YMMV
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