Hammond SE Transformer question - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 8th May 2004, 10:36 AM   #1
alk is offline alk  Europe
diyAudio Member
 
alk's Avatar
 
Join Date: Apr 2004
Location: tiny place
Default Hammond SE Transformer question

Hi,
I have just build my first tube amp and i was designing a nice rosewood box for it when i found my output transformer was just too big for this little amp- my mistake. I wanted to do a little and cute box.... The trafo is a hammond 125ESE. I have seen the smallest of the SE line rating 3W really cheap (Hammond ASE) and as my amp puts out 2w am thinking of buying it and use the ESE(15w) for a guitar amp(the amp i made is too clean for electric guitar).
My question is this: will i miss something in the sound?
I am happy with its sound but i plan to make another amp with some Russian valves i saw in the future. Will i repent if i replace the transformer? If somebody tells me the sound would change for worse i would not do it.
I'm not an audiophile but my ears are not fooled easily.
Thanks
Attached Images
File Type: jpg spcl86.jpg (50.1 KB, 518 views)
  Reply With Quote
Old 8th May 2004, 11:02 AM   #2
diyAudio Member
 
baggystevo82's Avatar
 
Join Date: Dec 2003
Location: Herefordshire
Send a message via MSN to baggystevo82
Hi,
So long as the primary resistance and the secondary taps are correct it should be fine. I think as far as transformers go, all other things being equal, the smaller they are the better the frequency response will be, though I dont know if this will be noticable. If it's rated 3W, has the right primary resistance and the right secondary taps, and is cheap, Id go for it. If you decide you dont like it you can always swap it back as you say you can get them cheap
I'm a beginner myself so dont take any of this as fact!! I'd wait to see what everyone else has to say on it...
Good luck,
Steve
  Reply With Quote
Old 8th May 2004, 01:56 PM   #3
alk is offline alk  Europe
diyAudio Member
 
alk's Avatar
 
Join Date: Apr 2004
Location: tiny place
Thanks Steve ...it is also my opinion but i'm also a beginner. People seem to relate big sound to big iron...i dunno
  Reply With Quote
Old 8th May 2004, 02:02 PM   #4
diyAudio Senior Member
 
fdegrove's Avatar
 
Join Date: Aug 2002
Location: Belgium
Hi,

Quote:
the smaller they are the better the frequency response will be,
At what end of the spectrum?

There's alot more than physical size to a good OPT but you just can't get any decent low frequency response out of a miniature sized one...

Cheers,
__________________
Frank
  Reply With Quote
Old 8th May 2004, 02:04 PM   #5
diyAudio Member
 
baggystevo82's Avatar
 
Join Date: Dec 2003
Location: Herefordshire
Send a message via MSN to baggystevo82
Hi,
Big sound needs big iron due to high power, or the transformer would get too hot. In the case of single ended amps they also have to cope with higher DC flow on the primaries. Your amp is 2W and using a huge opt won't change that.
Just googled for that transformer and apparently the 125ESE can cope with 80mA DC on its primaries and is more suited to single ended KT88 kind of power, which seems a little overkill. I think you should go with the ASE
Steve
  Reply With Quote
Old 8th May 2004, 02:08 PM   #6
diyAudio Member
 
baggystevo82's Avatar
 
Join Date: Dec 2003
Location: Herefordshire
Send a message via MSN to baggystevo82
Quote:
Originally posted by fdegrove
At what end of the spectrum?

There's alot more than physical size to a good OPT but you just can't get any decent low frequency response out of a miniature sized one...
I was on about losing top end with really big opt. Im just quoting out of Morgan Jones's book here, I haven't any actual experience apart from the amp I just built. I remember seeing on the sowter site some frequency response curves for their opt, maybe hammond do the same?
Steve
  Reply With Quote
Old 8th May 2004, 02:17 PM   #7
diyAudio Member
 
baggystevo82's Avatar
 
Join Date: Dec 2003
Location: Herefordshire
Send a message via MSN to baggystevo82
Hmmmm, it says on the hammond site that none of the 125 series are for hifi use
Steve
  Reply With Quote
Old 8th May 2004, 02:56 PM   #8
alk is offline alk  Europe
diyAudio Member
 
alk's Avatar
 
Join Date: Apr 2004
Location: tiny place
Hi Steve, here they don't think so.
http://members.myactv.net/~je2a3/125ESE.htm
  Reply With Quote
Old 8th May 2004, 03:01 PM   #9
diyAudio Member
 
baggystevo82's Avatar
 
Join Date: Dec 2003
Location: Herefordshire
Send a message via MSN to baggystevo82
Well theyre cheap anyway so you may as well try em...
According to hammond their response is 100Hz to 15KHz @-1dB and their hifi series is rated 20Hz to 20KHz @-1dB, dunno if you would hear a difference though.
Steve
  Reply With Quote
Old 8th May 2004, 03:06 PM   #10
diyAudio Member
 
baggystevo82's Avatar
 
Join Date: Dec 2003
Location: Herefordshire
Send a message via MSN to baggystevo82
Hi again,
I just read through a bit more of that link. I think they went for that one as you can configure it for lots of different primary resistances. It is a bit of a worry that two transformers acted so differently though Maybe if you bought more than you need (if they are really really cheap) and picked out the good ones?
Steve
  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
Hammond 269 EX transformer (never used) zenmh Swap Meet 7 4th August 2009 07:06 PM
Question about Allied & Hammond Power Transformer Ratings Bitrex Tubes / Valves 2 6th March 2009 07:31 AM
One Question for Hammond 1620 output transformer Menator Tubes / Valves 1 19th March 2007 10:51 PM
WTB: Hammond 269EX Transformer mrdon Swap Meet 0 12th April 2006 03:05 AM
Hammond Transformer in Toronto drcy Tubes / Valves 0 1st June 2004 02:18 AM


New To Site? Need Help?

All times are GMT. The time now is 06:56 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