[walkern]

I am considering buying and constructing a LF 55 amp and would love to buy transformers from an AC member if anyone has 2 to spare.  Used or new would be fine with me.

Neil

[AKSA]

Hi Neil,

Welcome to the forum!!

The issue of transformers, an expensive part of the amp, can be economically solved with these from


http://www.herbach.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=HAR&Category_Code=XFR&Offset=10&Previous_Stack_Depth=1


 
24 VAC 4 Amps Transformer - SINGLE OUTPUT
Code: TM99XFR3396
Price: $6.50
Quantity in Basket: none
 
Two of these in series will give you 48VAC, which is fine for the positive rail and a negative rail of around +/-35Vfpr a single channel. Same for the other channel.  Look on the third page.

Herbach and Rademan are here:

 General Contact Information: 
H&R Company, Inc.
353 Crider Avenue
Moorestown, NJ 08057 
 e-mail:  sales@herbach.com 
Phone:  (856) 802-0422 
Fax:  (856) 802-0465 
 
Sales  Technical Support 
e-mail:  sales@herbach.com 
Phone:  (800) 848-8001 
 e-mail:  support@herbach.com 
Phone:  (856) 802-0422 x313 or x315 
 
 
Depending on where you are (in the US??) this will give you two full +/-35V power supply for the LF55 at a cost of $26 plus shipping, which has to be some kind of bargain.  They will only deliver 96W per channel, but the overload margin is good (they are low flux EIs) and the lower capacity appears to have little influence on the sonics.

This is an amendment on my original post;  I'd mistakenly highlighted the wrong trafo at first.

I must thank Paul (aka Occam) for this highly valued link.  These are good quality trafos;  an AKSAphile bought some a couple of years back and they have been trouble free and quiet.

Cheers,

Hugh

[walkern]

Hi Hugh,

Thanks so much for the welcome and the link with recommendations. 
My goal wasn't exclusively to minimize costs (although that is great).  I was also hoping to avoid a 4 to 6 week wait for Plitrons... and you never know... sometimes nearby audioholics (I live in the Chicago area) take on projects that never get off the ground, or are a bit too ambitious, so buying some parts from a fellow music lover could be a win-win for all parties.

Very much looking forward to the LF 55 project.

Neil

[AKSA]

Folks,

Anyone know of any 25-0-25Vac 160VA toroids cheap for Walkern?

Hugh

[poseidonsvoice]

I don't know if its as much of a bargain as what Hugh just posted but if you don't wanna wait for Plitrons, then another very viable and good sounding option is Antek.

Here is the link:http://www.antekinc.com/trans.html

Best,
Anand.

[walkern]

Thanks Anand for the link.

Those transformers look like a terrific bargain.  Being a newbie to power amp constructing I'm not clear which of their transformers would work with an LF 55.  They have 100VA and 200 VA models (nothing at 160VA) that will each do 25 0 25 Vac.  Would it be safe to go with a pair of the 200 VA model? (item number AN-2225)

Neil

[poseidonsvoice]

As long as you got the secondary voltages right (check with Hugh if unsure), the 200VA model should be fine.

Again, you can always 'upgrade' to Plitrons later. The Anteks have good resale value and you don't lose much since they are cheap anyway. Total for the Anteks you have chosen including shipping in the U.S. is $70. Although transformer quality is important, the design topology is *more* important and that is where you have already hit a homerun with Hugh's work. The LF55 is on my short list for auditioning if not building. Its just that the dollar is complete crap at the moment.

Anand.

[AKSA]

Thanks Anand, much appreciated.

Yes, the 200VA would be fine, and if you listen to either sensitive speakers OR at low volume or both, the 100VA would save a few dollars and sound almost as good......

Neil, this is a good supplier by the look of it.....  it's clearly a good choice.

Cheers,

Hugh

[walkern]

Thanks Anand and Hugh,

Those transformers will fit in the case without a problem, and should work like a champ.
I do have high sensitivity speakers, but I tend to change often, so I'll probably go with the 200VA guys.

I'm going to give this thread a couple more run days just in case someone reads it over the weekend and has trannys they'd like to sell/part with.  If nobody pops up with something viable I'll go ahead and order amp modules and those transformers on Monday,

Thanks again guys,

Neil