SIMPLE SE amp design wanted - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 24th August 2003, 10:00 AM   #1
diyAudio Member
 
Join Date: Jan 2002
Location: Canberra, Australia
Default SIMPLE SE amp design wanted

About 3 years ago I began to be interested in building a Passlabs Zen amp.

To this end, I purchased a very nice 500VA C core tranny with twin 10 amp 0-25V AC output windings.

At the same time I got 4 nice low ESR 2200uf caps for use as output couplers and 8 80v 15,000uf electros for the PSU.

I've also got a couple of VERY substantial heatsinks to go with it, each about a foot long and 5 inches high with 2 inch long fins all along. Perfect for a class A amp.

My first attempt at breadboarding the Zen produced flames from the packages of the mosfets (not quite well enough secured to the heatsink) and since then Nelson has changed the scematics alot and many other folks ahve stepped up to pooh pooh the Zen design as well.

This leaves me with all the bits to make a great 30v rail PSU but no killer amp project to go with it.

Should I cut my losses, write off the C core and electros to the spares bin or can anyone help me out with a SIMPLE but stunning sounding SE amp that will use these bits. Or should I just track down an old schematic and build the Zen again?

I'm very much set on class A and the 30 seconds of music that emerged from the Zen prototype sounded stunning. I'd like to stay SE as well.

I have a preamp in the works that will happily feed more than 5V rms into a 5k load so the input impedance of the amp isn't too much of a drama. My speakers are single driver Fostex FE168sigmas with around 95dB/W and the room i'm listening in is only 12 x 18ft with 8 ft ceilings so I doubt much more than 10 watts would be necessary.

Help me (PLEASE)

Drew
  Reply With Quote
Old 24th August 2003, 10:17 AM   #2
mikelm is offline mikelm  England
diyAudio Member
 
Join Date: May 2003
Location: England
Send a message via Yahoo to mikelm
right now I'm listening to my own balanced wkg version of the john linsley hood's SE 'simple class A amplifier' and everything sounds more musically 'right' than I have ever enjoyed before.

a balanced version would not be the simplest but for discussion and diagrams of the original and improved versions look here.

JLH 10 Watt class A amplifier

I have heard that TimA's version is VERY good.

http://www.diyaudio.com/forums/showt...423#post201423

sometime I would like to get to listen to it

hope this helps

mike
  Reply With Quote
Old 25th August 2003, 04:59 AM   #3
Jay is offline Jay  Indonesia
diyAudio Member
 
Join Date: Feb 2003
Location: Jakarta
I have gone through Zen1 to Zen4 (and also JLH), and also Aleph3 and Aleph5 (and Aleph4.7, Aleph4.9, etc). I'm now using Aleph3 with no "Aleph" current feedback. I'm very tired of looking for better sounding amp. What I will do in your situation is exactly what I have done and partly what I'm going to do.

The 25V tranies are suitable for the Aleph3. With massive heatsink you can build a tower amplifier like a speaker stand, and hence a short speaker wire (I haven't seen such amp structure from pictures in this forum). You can bias the amplifier higher and get better result. You already have sensitive speaker. The 2200s are not useless, there are many possible/valuable tweaks in the CDP.

IMO, if you want a low power amp, you should not use too many gain stages from the source to the final amplifier. Use as minimum as gain stages as possible, and compensate the drawbacks with premium components and stabilization. CDP - SE AMP - Sensitive speaker (acceptable crossover), that's what I want to build with premium components and careful tweaks.

Remember, I'm not going to reccommend this setup (and the Aleph3 tweak) because people have "preference". If you are looking for highly dynamics system or better bass or sparkle highs or low distortion or sweet sound or better image or accurate sound, you may never found what you are looking for. Look for system that fills your listening sessions with joys. And trust me, you cannot achieve that by simply building "high end" systems.
  Reply With Quote
Old 25th August 2003, 05:59 AM   #4
diyAudio Member
 
Join Date: Jan 2002
Location: Canberra, Australia
Thanks for input foks.

I'm planning to run MC cartridge into single stage mc phonoamp, from there into a preamp based around a triode connected EL84 with choke plate load and thence onto a power amp.

Speakers have no crossovers at all, just the single fostex driver.

I was contemplating using the fet follower design that shows up from time to time as my pre will swing the 9v required to give me 10W out with no hassles.

At present the prototype of the phono stage is up and running but needs to be rebuilt with boutique parts (caddocks, AD797 and auricaps). Already sounds pretty good with cheap metalfilms, MKY p/esters and NE5534's so i can't wait till the next gen is built.

In theory, the follower would give me a total of one AD797, one triode EL84 and one mosfet in the signal path.

I have no intentions of going back to PFIYI (pay for it yourself), DIY is definitely the path for me since i found out in 1995 what it would cost me for the next hit (Sugden A21ap) to cure upgradeitis.

Keep the ideas coming,

...Enjoying the music

drew
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Simple Magic Eye Circuit Wanted poynton Tubes / Valves 8 26th November 2014 10:02 AM
Wanted. Simple EL34 Push Pull Design jack firebrace Tubes / Valves 51 29th July 2013 01:47 AM
Help (very much) wanted for simple quarter-wave design for cheap drivers. Spasticteapot Full Range 9 4th May 2006 10:14 PM
simple design power amp.. wanted. GeirW Tubes / Valves 12 30th January 2004 07:10 PM


New To Site? Need Help?

All times are GMT. The time now is 08:24 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2