GC SuperSymmetry

[juma]

Do you mean adapter PCBs (SMD to TH) from the BF862 preamp thread ?
If so, yes I have a couple more.

[buzzforb]

After looking at the thread again, I think i can make the bf862 boards myself. Am i correct in thinking that you use the version with the BF862 buffer, driven by your bf862 preamp?

[juma]

Originally Posted by buzzforb

After looking at the thread again, I think i can make the bf862 boards myself.

That's the way

Originally Posted by buzzforb

Am i correct in thinking that you use the version with the BF862 buffer, driven by your bf862 preamp?

Generally, yes. Right now, the main amp is this one

[buzzforb]

THis is very similar to the F5, correct. The oonly difference i see is tha you have dropped the protection circuit and the feedback circuit on the front end is different. I understand why you have droppped the protection circuit, since you know enough to not have to worry with them. I don't know that I see an advantage to the different feeback setup on the front end, but I may be missing something. Also, you have dropped the thermistors, which Pass says help with drift. Other than the different fets, am I missing something.

[juma]

Originally Posted by buzzforb

... am I missing something.

Just the whole thread ....

[buzzforb]

I have been known to do that.

[buzzforb]

I have boards for two F4 amps and was wandering if it possible to drive them with just opa1632. From datasheet it appears that its output voltage will swing to within 4-5V of the rails, so 15V rails should yield 20V swing, correct.

[sek]

According to it's datasheet specification OPA1632 swings to within (V-)+1.9V and (V+)-1.9V, respectively, when loaded by 2kOhm. Into 600Ohm this drops to 4.5V within the supply voltage levels.

For a +/-15V supply this would yeld +/-13.1V into 2kOhm and +/-10.5V into 600Ohm. That's 21Vpp into 600Ohm already.

I've attached the diagram showing output voltage vs. load resistance from the datasheet in order to better explain what I mean.

Cheers,
Sebastian.