Bill,
Do you mean the thread: "DAC output using a Transformer" started by jkeny? This thread has two pages... Or do you mean another thread?
Regards,
Lucas
Bill,
I hate to disagree on this and freely admit that measurement may say that I am totally out of line, but, subjectively, having loaded the secondary as per the Jensen circuit - and been very happy - I followed Bud's advice and snipped the secondary (only) loading. The result - again subjective - to my elderly ears, was that the whole soundstage became bigger, more precise but - most of all - the treble/top-end became sooo much more integrated and believable. I listen to solo classical piano, chamber music and (some) blues but all acoustical. The odd orchestrical CDs I have tried so far refle4ct the above and the top=end has become smoother, more integrated and lost most of the previous congestion.
I also tried some other stuff such as the 'TIME' track from Pink Floyd. That aching shrill alarm has become just bearable!!! Mind you I DO realize that many would prefer the risk of hospitalisation!!
EDIT
I forgot to mention that overall dynamics were also much more creditable.
the top=end has become smoother, more integrated and lost most of the previous congestion.
Brianco: that's exactly how I'd describe the top end at the moment, slightly congested with the 680 load across the secondaries. I'll snip it out and have a listen, before deciding whether to try the Jensen values or not.
He gave me the idea to buy it and he's right with his comments about this dac
Try it....I did! It is not too bad. But what I now have is far far better!
If you like the result of 'unloading' the secondary, then thank BudP!
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Basingstoke, born and bread (for my sins!) Lol! Where abouts did you used to live then?
Listening to the A20s sans 680-ohm resistor now and.... I'm not sure! Sounds extremely bright.... buuuttt this may be the recording - listening to the remasters of one of the James Bond soundtracks by the awsome John Barry... brass section almost taking my head off - liscence to shrill!!!
Will try something else now...
Listening to the A20s sans 680-ohm resistor now and.... I'm not sure! Sounds extremely bright.... buuuttt this may be the recording - listening to the remasters of one of the James Bond soundtracks by the awsome John Barry... brass section almost taking my head off - liscence to shrill!!!
Will try something else now...
Yes, it does expose bad recording and maybe it is a little shrill but if so it suits my nearly 70 year old ears!! But it does seem to dig into those compressed discs and drag out what is left of the music.
I was at school in Winchester and lived for a while when I left Ireland in Burley in the New Forest! A great friend is a coffee merchant in Basingstoke and we are fishing together in a couple of weeks in the Hebrides.
Further listening definately reveals a harsh/bright treble, at least to my ears. Bass seems to have taken a few steps backwards too. Will leave it for another day or so but I think I prefer the sound with a load across the secondaries so far.
ahh Winchester - fabulous place, and great area to have gone to school in I imagine!
Coffee... another passion of mine
ahh Winchester - fabulous place, and great area to have gone to school in I imagine!
Coffee... another passion of mine
I have in hand UTC HA108, Lundahl LL1690, Studer, Tamura -Yamaha GA80080 and Panasonic Ramsa console transformers. When not properly loaded at their secondary, they are harsh sounding and with a scope, you can see ringing at 20 khz on most of them. 600-1000 ohms of loading gives me the best results with the 600 to 600 transformers. (Not the LL1690)
The CS4398 must be loaded at MORE than 1000 ohms so if the load at the secondary of the transformer is 600 ohms you must at least use 200 ohms resistors at each leg of the primary to the dac.
When loading the secondary, you'd better look at the input impedance of your preamplifier if you don't want to go lower than 1000 ohms at your primary.
I have to be honest, I only had the A-20s for a few days and I didn't try them without the RC filter. I did find their sound exactly as you described with the filters in place. I assumed the filter would be inaudible, as I use it with my Sescoms with absolutely no sonic penalties. Now I'm going to have to find another pair of A-20s to mess with.
Best, Bill
It seems to be mellowing out now, treble isn't taking my ears off quite so much. Still sounds a bit hard edged though. Still detail is amazing, and I can see how lovers of classical or acoustic music in particular may love this sound. It doesn't seem much good for rock or anything with a good bass line though (and bass is what I loved the most about the A20s, with loaded secondaries), at least not at the moment.
So I think I'll take your advice Legarem and load the secondaries again. In this case I'll use the values recommended by Jensen (I already have their values on the primaries).
- J
So I think I'll take your advice Legarem and load the secondaries again. In this case I'll use the values recommended by Jensen (I already have their values on the primaries).
- J
In the light of the above I have reconnected the R (1K) across the secondary.
The whole soundstage and precision of imagry has contracted - become closer to the center. The sound envelope has shrunk a lot in depth and spread. I have to admit that my upper hearing is not the best, so perhaps the straight out from the Tx is more suitable in my case!!!
Reading the other DAC posts it seems that this DAC is no longer the best value budget DAC...the Behringer for example seems to be for not much more money have more potential.
The whole soundstage and precision of imagry has contracted - become closer to the center. The sound envelope has shrunk a lot in depth and spread. I have to admit that my upper hearing is not the best, so perhaps the straight out from the Tx is more suitable in my case!!!
Reading the other DAC posts it seems that this DAC is no longer the best value budget DAC...the Behringer for example seems to be for not much more money have more potential.
JUST when you think you've got the best you can get (for the money spent) something else ALWAYS comes along hahaha! In this instance ignorance is bliss, and I am going to force myself to continue getting the best from this DAC.
Brianco, have you tried any other resistor values? What have you got on the primaries?
It does sound VERY open without any load - if the treble would smooth out a little and the bass open up again I'd be extremely happy with it. Seldom heard a DAC as open as this one.
Brianco, have you tried any other resistor values? What have you got on the primaries?
It does sound VERY open without any load - if the treble would smooth out a little and the bass open up again I'd be extremely happy with it. Seldom heard a DAC as open as this one.