Here's a snippet from This Article from AEA,
"We also add one or more high quality, high capacitance polypropylene types in parallel, allowing higher frequencies in the return signal path to bypass the electrolytics, thus avoiding the problem. One might ask why this is not done by most other system designers. The answer is simple: It adds more than ten times the cost of power supply capacitors. But if you value sound quality, it’s well worth it."
Thoughts on this?
"We also add one or more high quality, high capacitance polypropylene types in parallel, allowing higher frequencies in the return signal path to bypass the electrolytics, thus avoiding the problem. One might ask why this is not done by most other system designers. The answer is simple: It adds more than ten times the cost of power supply capacitors. But if you value sound quality, it’s well worth it."
Thoughts on this?
Difference between 0.22uF and 0.25uF is negligible in this case.
Inside a feedback loop (like in the MkIII), audible differences among parts are diminished.
Beyond the electrical requirements, the choice is mostly a personal matter.
I didn't know those guys were still in business.
That's more about power supplies than coupling capacitors.
If it would improve or degrade performance would have to be measured with special instrumentation. In some cases there may be a benefit, in some cases it could cause problems. It depends on the impedance characteristics of the electrolytic capacitor. Some behave very well all by themselves.
Capacitors always come with a tolerance. If you are specced at 0.25uf +/- 10% then you will be able to swing between 0.225 and 0.275 and still stay within design parameters, before even starting to look at the practical effects. As mentioned, the effects of 0.02uf won’t be reproducible by your speakers.
Most electrolytic caps have much worse tolerances. +40/-20% is common.
Beware anyone looking to profit from your insecurities about a topic. Even if you don’t buy something from them directly, their language is such that it’s designed to make you feel inferior. “You OBVIOUSLY don’t care about sound if you’re not buying $30 capacitors” is one way they make you feel dependent on their “expertise”.
Unless it's a lot less than this one, new is better.
http://www.saelig.com/ds1000e-series/ds1052e.htm
http://www.saelig.com/ds1000e-series/ds1052e.htm
Well, if it works and also has the x10 or x100 probe, seems ok.
It does only have one channel, remember. But that's not a deal breaker.
Maybe you can fix the tube tester, or sell it for parts so the scope is free.
Using too large of a film-type bypass capacitor starts to defeat the purpose of doing it in the first place. A 1 uF polypropylene cap will have less inductance in it than 100 uF will. For wide band RF decoupling, the standard practice is to use multiple caps in parallel, separated by two or sometimes even three decades in cap value. The worst thing you can do is have the caps too close together in value if the goal is to prevent feedback through the supply lines.
You think I should hold off and wait then? I like the 1 year warranty. I haven't seen that anywhere.
The MkIII was designed for the 6550/KT88 tubes. The output transformer won't
electrically match with the EL34/6CA7 tubes, though no doubt someone has tried
to get such a mismatch to function. Bad things could easily happen, best to wait.
I connected my amp to an Altec A6 and it had the proper balance, so I changed the crossover in my Altec A5 and now I am on the right track.
While I'm waiting for the KT88's I got a couple of these Yellow Jackets to try out. They sound good. Plenty of power.
While I'm waiting for the KT88's I got a couple of these Yellow Jackets to try out. They sound good. Plenty of power.
There is a Mark II(2) available locally for $200. Can I turn it into a Mark III less the 4 ohm tap? Thanks
I found this Dynaco Mark II to Mark III conversion
What I am wanting to do is get a Mark III chassis and swap the parts over with a Mark III pcb. That way my amps will match.
What I am wanting to do is get a Mark III chassis and swap the parts over with a Mark III pcb. That way my amps will match.
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Received my tubes! Is it normal for new tubes to pop and crackle before they are broke in? I've had to adjust the bias twice and the screw is over to the 4th quadrant. I've been running 2 different sets of EL84 yellow jackets previously for a week or 2 without a hitch. I put them back in and there is no popping. It would have been confidence inspiring if the numbers on the tubes matched. The numbers written on the box are close, though. My U-Test-M shows them @ 72 and 76. Sencore shows them @105. TIA
