Diodes and Transistor

[speakerman1]

What is ESL?
Diodes Soft recovery, speed.
Transistors in general.

Here is the talk in the DIY forum.Some of these things are greek to me.LOL

http://www.diyaudio.com/forums/solid-st ... reamp.html

Go to the links in the post after mine.That is where these guys get deep.

Larry

 

[laatsch55]

Do you mean ESR?? ESR is equevalent series resistance and is a spe c for a cap to give you some idea how well it's going to do it's cap thing. I built the BLUE ESR METER and it's invaluable in screening bad caps out, also helps in matching caps ANDS is an excellent meter to measure less the 1 ohm resistance. Excessive resistance in an electrolytic can have a very large effect on gain, clarity and frequency response.

 

[speakerman1]

I have this. Will it work?

http://www.mcmelectronics.com/product/T ... 0-/72-8150

Larry

 

[Web Police]

Diodes and Transistor You mean Dog and Butterfly? The Heart Thread is several aisles that way ---------->

 

[laatsch55]

No Larry that will not measure ESR. Although that would be a good meter to have. It measures hfe in a tranny, that's handy.

 

[speakerman1]

That is a Capacitance meter.I have an inductance meter also. You were talking about Henrys right?

Larry

 

[speakerman1]

Getting some more resistors.Order shipped yesterday. And some Solens.They are working on some prices of some of the WO and my Pre and Hafler upgrades.

Larry

 

[laatsch55]

No, Equivalent Series Resistance is measured in Ohms. Inductance is measured in henry's.

 

[speakerman1]

I'm losing it. I may get one who knows.I have no idea what I was thinking about.

Larry

 

[nakdoc]

The MCM meter does not measure ESR. ESR is really only a factor in switch mode power supplies and fast digital stuff. For regular audio, other properties like construction are more important.
soft recovery has to do with switching speed. Any diode or transistor junction will store a bit of charge. When it is switched (as opposed to class A operation) this charge slows the switching speed down. You'd think this would only be a problem in digital, but in fact audio, especially power amplifier output transistors, and all PWM drive systems must have the correct speed transistor installed. A few years ago DIYers went nuts over fast recovery diodes in power supplies. While it doesn't hurt, in my opinion it is overrated. Can you tell I'm highly biased? Soft recovery is considered slow.
Transistors in general....big subject. Can you ask a less broad question?

 

[laatsch55]

ESR is a very large factor in crossovers in particular, lose a bunch of gain there and everything sounds like s&^%!!

 

[speakerman1]

The MCM meter does not measure ESR. ESR is really only a factor in switch mode power supplies and fast digital stuff. For regular audio, other properties like construction are more important.
soft recovery has to do with switching speed. Any diode or transistor junction will store a bit of charge. When it is switched (as opposed to class A operation) this charge slows the switching speed down. You'd think this would only be a problem in digital, but in fact audio, especially power amplifier output transistors, and all PWM drive systems must have the correct speed transistor installed. A few years ago DIYers went nuts over fast recovery diodes in power supplies. While it doesn't hurt, in my opinion it is overrated. Can you tell I'm highly biased? Soft recovery is considered slow.
Transistors in general....big subject. Can you ask a less broad question?

I'll have to go back and read all the posts.It was about the power circuit. The transistors I can' remember.They were using a bunch of numbers.

Larry

 

[avionic]

Picked up a new real neat little tool a couple weeks ago.
http://catalog.anatekcorp.com/viewProdu ... _id=497385
This DCA55 is amazing.Sure beats the hell out of the piece of crap I was using to Hfe match transistors with.
Also cheaper to purchase direct from PEAK in the UK.

 

[nakdoc]

ESR is a very large factor in crossovers in particular, lose a bunch of gain there and everything sounds like s&^%!!

Actually, no, unless you are crossing over at 10 kHz or higher. Again, it doesn't hurt to have low ESR, but for high frequency crossovers good design dictates mylar or poly caps anyway.Something called "Power factor" is important in electrolytics in crossovers. I don't know the details, but higher power factor caps are physically larger, so I just use the biggest ones I can find!

 

[laatsch55]

Ok, is it safe top say high ESR in a signal path cap is detrimental to the sound??