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Silk Transformers

Anyone have any experience w/ silk transformers?
I could have sworn I read a few things about them here, but my search just came up w/ nothing.
I guess if anyone knows, how do they compare to the James? Silk (as a company) is very responsive, and James took a month to get to my email. Euphonia has NEVER responded to several emails over the past couple of months, so James just isn't working out for me.

I'm looking for a decent, good value 300b se transformer.

thanks
 
Electra-Print is twice the cost of the james or silk transformers. (unless his prices are per pair, but i doubt it. His website doesn't say they are listed as a pair).
$450 is more than I wanted to spend, but I would if they would be twice as good as the Asian transformers! :)
Urg.. I've been dreading this part of the build. Everything else is figured out and ordered, but it's really tough to feel good about the transformer purchase. There are so many mixed reviews and variables, and different methods of construction, etc.
 
wicked1 said:
Electra-Print is twice the cost of the james or silk transformers. (unless his prices are per pair, but i doubt it. His website doesn't say they are listed as a pair).
$450 is more than I wanted to spend, ...

Which EP's are $450? I don't see anything approaching that price except the ones with partial silver secondaries.
 
Ah... if I'm willing to give in and spend almost $500 on transformers, it opens up all sorts of new possibilities, doesn't it? The lundahl's are actually less expensive than the EP's! I could even go w/ amorphous core for about the same price as the EP's. (depending on if I chose the 1660 or 1620 series) I've read a lot of good things about amorphous cores, but then the EP website says they aren't as good as a standard core.

Making decisions sucks.
 

zarniwoop

Member
2003-11-11 11:06 pm
NY
I have the james in a 300b amp. Not much useful to say about them sonically since no comparisons made so far. Another plus, aside from price, is that they look better in their potted covers. I'm sick of the standard exposed transformer painted in black look. If you're gonna cover up winding/bobbin/leads with a couple steel covers I don't see why you just don't go all the way and make it look less obnoxious with a potted enclosure. Just a thought.
 
I have used Plitron's 3035SE OPT in my 300B mono's for few years. It has very good frequency response upto almost 100KHz. However, I don't like the sound of it much.

The Lundahl 1620AM amorphous OPT has much more natural sound breathing out music.

If you want to build the 300B amps, I would recommend the LL1623AM 80mA. I would say it is worth in this investment. You may buy the cover of OPT to make it look nice if you want.


Johnny
 
One the main differances between Eletra-Print transformers and the Asian ones will be the primary inductance. For some reason, all the Asian designed OPT's I have tried always had much lower inductance - i.e. weaker bass.

There are also drawbacks with excessive primary inductance. Inductive & capacitive parasitics and in many cases a higher DCR.
 

MQracing

diyAudio Member
2005-10-08 4:11 pm
www.magnequest.com
zarniwoop said:
If you're gonna cover up winding/bobbin/leads with a couple steel covers I don't see why you just don't go all the way and make it look less obnoxious with a potted enclosure. Just a thought.

the drawback to potting transformers is that the potting material adds significantly to the capacitance of the trans. If you test the same trans before potting in a can and after potting in a can you wll generally see the freq response droop earlier and if you look at some 10 or 20 khz square waves before and after potting you will also generally see some degradation from the potting materials.

And the most common modern potting materials have not so good dielectric constants and dissapation factors.

potted tranneys may look pretty but unpotted tranneys more often sound pretty :=)

msl
 

MQracing

diyAudio Member
2005-10-08 4:11 pm
www.magnequest.com
Jeb-D. said:


There are also drawbacks with excessive primary inductance. Inductive & capacitive parasitics and in many cases a higher DCR.


This is too broad a generalization. It's possible to design a PP output trans with very high OCL (say a hundred henries per thousand ohms of nom pri impedance) and with proper coil design (i.e., interleaving) keep the leakage L at very, very low levels (say 1 mh per thousand ohms of reflected primary impedance) and keep the winding resistance low enough that your insertion losses are at .25 db (that's point twenty five DB). And get high frequency response in excess of 100khz at minus 1 db.

These are some of the characteristics of a high quality output trans. Sadly, your probably not going to build to this level at Hammond prices.

MSL