build by Nelson Pass

[meanman1964]

I have a question;did Nelson Pass build an amplifier called A18?

 

[meanman1964]

This amplifier has been made by Nelson Pass and John van der Sluis.The amplifier has output-toroids and you must set the bias together with the loudspeakers while the amp is working.

 

[GRollins]

Nelson is not known for using output transformers.

Grey

 

[meanman1964]

Nelson is not known for using output transformers.

Grey

And what in the early days?I maild Nelson but he didn't reply yet.

 

[GRollins]

I think you've pretty much answered yourself.
Nelson's early days would have been the '70s. Toroids used as output transformers didn't become popular until the '90s.
Do you have a link to this putative circuit?

Grey

 

[jacco vermeulen]

and John van der Sluis.

You have a sense of humor.
van der Sluis knows squat about designing amps.

 

[GRollins]

I took a moment between one emergency and the next and Googled the guy. I'm assuming you derived Nelson's name from a review that says:

"A similar, if somewhat more extreme, style can be found with Nelson Pass' Zen designs of single-ended MOSFET amps..."

They are comparing the A-18's circuit to Nelson's Zen amps, saying that both are examples of minimalist circuits. They are not saying that Nelson had anything to do with the A-18 design.
For what it's worth, they also make a comparison to Jean Hiraga. Again, they are not saying that Hiraga had anything to do with the design.

Grey

 

[meanman1964]

I think you've pretty much answered yourself.
Nelson's early days would have been the '70s. Toroids used as output transformers didn't become popular until the '90s.
Do you have a link to this putative circuit?

Grey

My brother gets this amp this week I'll keep you posted about the amp.My brother is thinking that it is a Pass amplifier and he asked me if it is.I told him I look it up.Maybe it is a modified amp,I only know for sure if I see it.I let you know in time if you're interested.

 

[meanman1964]

I took a moment between one emergency and the next and Googled the guy. I'm assuming you derived Nelson's name from a review that says:

"A similar, if somewhat more extreme, style can be found with Nelson Pass' Zen designs of single-ended MOSFET amps..."

They are comparing the A-18's circuit to Nelson's Zen amps, saying that both are examples of minimalist circuits. They are not saying that Nelson had anything to do with the A-18 design.
For what it's worth, they also make a comparison to Jean Hiraga. Again, they are not saying that Hiraga had anything to do with the design.

Grey

That's the same what I told my brother.The guy that sold the amp to my brother said it's a Pass Lab.We'll see.

 

[GRollins]

Assuming the circuit I saw was anything like the one your brother is buying, I think it's safe to say that the A-18's use of MOSFETs for the output stage is about as close as it comes to Nelson's designs.
Of course, there are (ahem) one or two other designs that can make that same claim, so you could also say the A-18 was like any number of other amplifiers...and by extension like their designers' philosophies.
It's a dead issue.

Grey

 

[GRollins]

He said specifically that it's from Pass Labs? That's getting close to legally actionable. Return the amp. Get the money back. Tell the seller to take a hike.
Again, assuming that the schematic represents the amp your brother is getting, there is no resemblance between that amp and Pass Labs product.

Grey

 

[meanman1964]

Maybe it's his own design I don't know.When my brother gets this amp I take a picture of it.He had trade it for a set of speakers.

 

[Nelson Pass]

In any case, I am unfamiliar with any of it.

 

[meanman1964]

In any case, I am unfamiliar with any of it.

Hi Nelson,
For me this is the answer I was waiting for. Many people think they have design of you when they see your name in the manual or so.But I keep you posted what kind of amplifier it is if you want.

 

[meanman1964]

Here's an update,my brother was wrong.It's a Hawk A15.I do have picture of the amp,if anyone wants to see them let me know.For me this thread is closed.