First Watt F7 review

[lhquam]

Who cares about grounding...I want to see more zd25 pics and a schematic!

Pics in post #1291. Schematic? Maybe at some later time.

 

[Cortez]

Nevertheless, because it is important to you, this morning I took an F7
and put it on the bench and measured the following with my trusty AP.

Wow, thanks a lot Mr. Pass I greatly appreciate you took those tests, it's really generous from you!
I didn't want to bother you with this issue just beeing curious how such a GND layout doesn't cause any major hum.
It's intresting what the simulated model was missing if the real life measurements are so different.
Thanks anyway!

 

[Nelson Pass]

Your welcome, and I was also interested in getting some testing on it,
but in the end ZM the made me do it.

 

[Zen Mod]

yup

as usual , blame on me

 

[Dennis Hui]

ZM the made me do it.

Hah! That's wonderful.

Thank you Papa for the measurements.

(Will also remember that line the next time I have to explain why another box of parts shows up... )

Dennis

 

[Antoinel]

Please see the last post in the thread "Compound power amplifiers'. It shows the schematic of a powerful power amp which embodies positive current feedback.

 

[Juntuin]

Can't wait until Mr. Pass publish F7 schematics This is probs best option for electrostatics in first watt range since it handles reactive loads so well. Is it still many years away?

 

[vdi_nenna]

Can't wait until Mr. Pass publish F7 schematics

You should be excited, if the schematic comes out. These are great amps! I have two simulated F7s doing highs and mids duty, plus a F5T v2 on the woofers. Got some great reviews from my audio group yesterday. They seemed to really like the sound. They liked my DIY speakers, but I gave all the credit to the power amps and B4s!

 

[Juntuin]

You should be excited, if the schematic comes out. These are great amps! I have two simulated F7s doing highs and mids duty, plus a F5T v2 on the woofers. Got some great reviews from my audio group yesterday. They seemed to really like the sound. They liked my DIY speakers, but I gave all the credit to the power amps and B4s!

Wow, what an arsenal of Pass amps!

 

[vdi_nenna]

Wow, what an arsenal of Pass amps!

You don't know the half of it!
The list is long and distinguish!

 

[Dennis Hui]

Hey Vince,

Tri-amping is a great way to use amps you've built.

Any update to the "family photo"?

Pass Amp Family Photo Summer 2017

Cheers,
Dennis

 

[vdi_nenna]

Any update to the "family photo"?

Just MoFo monos and another BA3-Pre with switchable gain. 6w vFet amp went to another family. 25w SE Schade feedback amp on the bench next.
Oh, and mosfets F6 needs surgery, but it will be just fine!

 

[Soundhappy]

General Electric old book with chapter about positive feedback in transistor amplifier page 215

http://www.introni.it/pdf/GE - Transistor Manual 1964.pdf

 

[Ian Macmillan]

The link does not seem to work...

 

[generg]

It works fine for me.

 

[Ian Macmillan]

Strange. This is what I see.

 

[nicoch58]

link work... maybe brexit

 

[Soundhappy]

It works fine for me.

For me too

Strange. This is what I see.

What is your web navigator software ?
Try some different one , maybe another do work better.
Book with many interesting chapters. Good luck

 

[El Reino]

General Electric old book with chapter about positive feedback in transistor amplifier page 215

http://www.introni.it/pdf/GE - Transistor Manual 1964.pdf

Thanks

 

[Ian Macmillan]

I am using Windows 10 default so Microsoft Edge.

Just tried another browser as suggested and it works just fine. So either Brexit or Microsoft clearly causing the problem...

Thanks for all the replies.