A Concise Guide to the Published Amplifier Circuits of Nelson Pass

[DBGaither]

Does anyone have a copy of the Concise Guide? The hosting website is no longer functioning.

 

[rsdio]

Hi folks,

As a few people have noticed, my old sounds.wa.com domain is gone. Long live audiobanshee.com! Note: I edited the first post to correct the link.

Brian

 

[poli]

Thanks Brian,
really good work!

 

[jdg123]

phase reversal

As I age I need to ask for help from younger minds: is there a Nelson Pass design that leaves the final phase inversion to the user (reversing black and red speaker terminals)? I found no mention in this guide but I have this notion that there is one...BOZ maybe?

 

[Zen Mod]

you can do that on any amplifier , speakers being floating devices

 

[jdg123]

Good point!

I just wanted to know if, like some Conrad Johnson designs, NP came up w one and similarly concluded it was simpler to have the user do the last phase inversion.

 

[Nelson Pass]

If I do that, I label the output terminals so that the user will connect the
positive of the speaker to the "red" and negative to the "black" and then
I tell them about it in the manual in case they are connecting something
else to the loudspeaker and need to know who is Ground.

 

[2 picoDumbs]

Very nice. Straight to the point.
There are quite a few designs that are missing though.

 

[needtubes]

Looks like it hasn't been updated for a while. Perhaps we are at the point where a Wiki guide to all the circuits with links to forum posts containing circuits of interest would be beneficial to all? I know I am curious about more than one circuit which has a thread running to hundreds of pages...

 

[woody]

Here is an interesting patient of Nelson's was it ever made into
a working amp?

 

[BeardyWan]

Newbie question.

Does this mean that you can take some `nice' semiconductor and cascode it with a monster hockey puck: some super delicate jfet/SIT/vfet and hang a great big high gain switching lump on the side and get all the nice character of the `audiophile' device with much bigger output?

 

[bfburkejr]

Pass Aleph 1.2 circuit boards

Hello,
It has been a couple of years since I have been on here due to operations and Hospital stuff, I was wondering if the following website is still reliable
http://www.kk-pcb.com
for ordering circuit boards for Aleph amps and power supplies, I haven't decided what to build. I might do a set of powered speaker like the ones Nelson did a while back with multiple Aleph amps inside. I prefer active crossovers and sealed cabinets with DSP for bass extension. I can't find any current comments on the reliability and quality of the circuit boards and stuffing lists that come with them on this site. Anyone know anything?
Thanks,
Brian Burke

 

[jimbo51]

You would do best by first looking at the diyAudio Store to see what is now available in legitimate PCB's.

Amongst the many items you will find a universal power supply board suitable for any First Watt amp.

 

[powerslave]

Sorry if this is a lame question; which of the FW power amps are easiest to build in terms of procuring components ? Assume that I have the cabinet and heat sinks all covered by buying a super chassis that could support all FW builds , my goal is to build a keeper i.e. to choose a topology and design that I can keep running without worrying about procuring exotic JFET/MOSFETs . Background to this question is I tried to embark upon the F6 build but I am finding it hard to procure output transistors so dropped the plan , I have no affinity for F6 and I am open to other FW designs that can output similar power.

 

[Zen Mod]

strictly speaking of level of ease in obtaining all the parts , it would be Babelfish J , then M2x

with later one you still need to find a way of smuggling Edcors in your neck of wood

 

[Itsmee]

Easiest to build, Amp Camp, JFET's and kits can be bought at the store (link at the top of the page).

The BA1, BA2, BA3 are very flexible, BA1 (with single ended output stage) is closest to Aleph J/J2 sound, while the BA3 (with complementary output stage - ideal for low impedance speakers) will take you more in the direction of the F5 sound.

You can add 'flavour' with the BA3 P3 preset, Iron Pre, H2 Harmonic Generator, B1 Preamp with Korg triode, or what ever takes you fancy.

 

[pinkfloyd4ever]

Anyone have that document that's linked to in the first post of this thread? Looks like the link is broken again.

 

[Zen Mod]

saved in my 'puter:

 

[rsdio]

My site was down from late February to late April due to server issues, and the nationwide shutdown made it difficult to repair things.
The site is up now, though.

 

[jeremya]

Thanks, Brian. Strong work.