Upping the Watts - Page 2 - 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 20th January 2014, 04:48 PM   #11
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
Input voltage to the transformer - I think you mean transformer secondary voltage (input voltage to the amplifier).

The table does show that 30V gives 60W into 8R, but you can't do this with the standard circuit. Notice the high power circuit has a different design (uses constant current sources) and with two pairs of output transistors still is only safe for 40W. Also the split power supply means there are two secondaries (each 30V using your example). You would need another pair of output transistors, and possibly some increase to the current in the voltage amplifier stage, again which takes some knowledge of the implications and may result in instability.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more.
  Reply With Quote
Old 20th January 2014, 05:35 PM   #12
diyAudio Member
 
Join Date: Apr 2003
Location: stockton on tees
Quote:
Originally Posted by j baldam View Post
Hi
there is a table featured in an update to the original design that seems to suggest that the output wattage is dependant upon the input voltage of the transformer. As the input voltage rises the output wattage rises.

The Class-A Amplifier Site - JLH Class-A Update
a secondary voltage of 30v will give 60 watts into 8 ohms.
Could I stand corrected or is that my original thought from my post.
hi ritchie, I meant the input voltage to the board from transformer,secondary.

1969 version, if I'm limited with this design I'll try to get as many watts as poss. I think the limit may be 15 watts.
  Reply With Quote
Old 20th January 2014, 05:38 PM   #13
diyAudio Member
 
still4given's Avatar
 
Join Date: Oct 2004
Location: Victorville, CA
I have the 1969 version. You may be surprised just how much sound 10W will give you.
__________________
X-BoSoZ, B1 Mezmerize, P101, Symasym, KSA 50, Aleph-X, Leach Low TIM, Leach Superamp, Dx MKIII, Super A, Honey Badger, JLH 1969, Gainclone. FetZilla, Peeceebee, VSSA PMI & jkuetemann, SKA GB150, Ovation nx & sx, AX&SX-14, TMG8, Slewmanster w/CFA-XH, Wolverine, Spooky, Symasui, Low TIM hybrid
  Reply With Quote
Old 20th January 2014, 06:08 PM   #14
diyAudio Member
 
Join Date: Apr 2003
Location: stockton on tees
Aye, 10 watts could probably be enough, sensitive speakers, small room.

Just thought I'd up the power whilst using better bits.

How do you find the JLH.
  Reply With Quote
Old 20th January 2014, 06:28 PM   #15
diyAudio Member
 
still4given's Avatar
 
Join Date: Oct 2004
Location: Victorville, CA
I'm actually pretty impressed with it. Hard to believe so few components can give such good sound. I built mine to test out using a server power supply for audio. I haven't installed it in a case yet because I want to try some different power supplies with it first. The server power supply is way over kill at 47A but it puts out 26VDC which the amp seems happy with. I used MJ15003 outputs. Mine was not a kit. It was built using the Jim's Audio boards.
__________________
X-BoSoZ, B1 Mezmerize, P101, Symasym, KSA 50, Aleph-X, Leach Low TIM, Leach Superamp, Dx MKIII, Super A, Honey Badger, JLH 1969, Gainclone. FetZilla, Peeceebee, VSSA PMI & jkuetemann, SKA GB150, Ovation nx & sx, AX&SX-14, TMG8, Slewmanster w/CFA-XH, Wolverine, Spooky, Symasui, Low TIM hybrid
  Reply With Quote
Old 21st January 2014, 06:09 AM   #16
diyAudio Member
 
Join Date: Jul 2003
Location: Dona paula, Goa
JLH is a Class A amp. Makes all the difference.

Gajanan Phadte
  Reply With Quote
Old 21st January 2014, 09:14 AM   #17
diyAudio Member
 
Join Date: Apr 2003
Location: stockton on tees
Thank you for the helpful replies, more confident of a result now.
  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
ucd 25 watts to 1200 watts using 2 mosfets andrewlebon Class D 3906 20th December 2014 06:37 PM
Upping voltage on a toroid carlmart Solid State 7 1st September 2007 11:56 AM
Sound quality of amps at 0.3 watts vs @ typical 5 watts rick57 Solid State 2 26th March 2005 07:25 AM
Upping the bias on Aleph 2 Mark A. Gulbrandsen Pass Labs 15 15th November 2003 08:16 PM


New To Site? Need Help?

All times are GMT. The time now is 10:13 AM.


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