I've found a pair of Altec 15356A transformers locally. Would the resistor (680 ohm) and capacitor (.00047 uf) values mentioned earlier be appropriate?
Does anyone know what size octal socket I should be looking for?
Last, these used transformers will run about $60 (for the pair) plus the sockets. Is this a good investment or would I be better off going with something else. Trying to be cautious since I've already been burned once buying something online that was not as advertised.
Steve
Does anyone know what size octal socket I should be looking for?
Last, these used transformers will run about $60 (for the pair) plus the sockets. Is this a good investment or would I be better off going with something else. Trying to be cautious since I've already been burned once buying something online that was not as advertised.
Steve
Atlplasma said:
I wouldn't be afraid to buy them, they have good specs from a good manufacturer.
The primary circuit should have at least 250 ohms in series with the trafo leads with a small cap (.002) across the leads. Bigger resistors would use smaller cap, ie, with 500 ohms you would use .001.
Secondary just needs an RC circuit across it, like 1K in series with a .001 cap.
Exact values aren't important, feel free to experiment.
Best, Bill
Richie ma said:
well my dac is up and running...now just waiting on some transformers from Harbuch...anyone interested in some more info can check out a blog i started i on this project, i have kept it pretty simple cause i have some non audio types interested in it..
http://bibdim911.blogspot.com/
deadpool said:
well my dac is up and running...now just waiting on some transformers from Harbuch...anyone interested in some more info can check out a blog i started i on this project, i have kept it pretty simple cause i have some non audio types interested in it..
http://bibdim911.blogspot.com/
Some time ago I had Harbuch made couple of 500VA toroids for mods I did on integrated amplifiers. They BOTH started buzzing loudly to a point where both had to be REPLACED...
Boky
I have a Beresford 7510 and this DAC with 4397 chip. It's slightly modified in that all coupling caps have been removed, a few resistors have been added and only one opamp is being used(LM4562). It's better than the Beresford - more weight and better mids. But the Beresford has nice air and for the price offers a lot connectivity options. I'm presently working on the "transformer thing" on a second board(4398) which will hopefully eclipse both.
danrap said:Hi everybody
Someone have compared the dac (as is, without the trafo mod) with a beresford 7520 or dacmagic?
I want to buy a new dac but I don't know what is the best for money..
thank you so much!
dan
I have the 7510. It's cheap, cheap components and even I changed the opamp it's still a cheap dac
McCrackers said:
Hi McCrackers, thank for the reply (and thanks to Piero 7 too )
I don't want to do the "transformer thing" because it cost too much for me.
Do you think that the "only one opamp thing" http://lampizator.eu/LAMPIZATOR/LAMPUCERA/MAX/opamped_lampucera.html
is it possible on the cs4398 version of this board too?
I have a dual burson discrete opamp and I'm happy if I could to use in this dac..
Thank you so much,
Dan
danrap said:
You can use Monacor LTR110 trannies. They are dirt cheap and they performs near as good as Sowters. I tested them and liked them very much, look there:
http://lh4.ggpht.com/_o-j1QGIOpHQ/Sk1eb0gzXhI/AAAAAAAAACo/IETxAcAcAec/s800/analog.jpg
http://audiosurgery.beepworld.pl/dacki.htm
I also tested "only one opamp thing" and I was not impressed. Synthetic, plastic sound, and the feeling of "being there" has completely gone. Not recommended.
You better try tube output stage like this:
Attachments
danrap said:thank you very much McGyver
Monacor trannies costs 15$..
Who knows if are better the monacor trannies or discrete burson opamps??
I haven't tested burson opamps, and I'm not even think about it. Circuits with tons of NFB aren't listenable for me.
Monacor trannies do the right thing. Go for it.