Hi you all!
I recently bought that LM-dac3 and before I connect anything up, I would like to ask the board if there is a cumulative guide of shoulds and musts for bettering its output quality?
I could spend hours to read through the entire collection of responses.. but I have limited knowledge and understanding of all the details, the whole thing is clearly out of my league, but I have one weakness, I like toying around..
thank you everybody
best to you all!
regards
angelo
I recently bought that LM-dac3 and before I connect anything up, I would like to ask the board if there is a cumulative guide of shoulds and musts for bettering its output quality?
I could spend hours to read through the entire collection of responses.. but I have limited knowledge and understanding of all the details, the whole thing is clearly out of my league, but I have one weakness, I like toying around..
thank you everybody
best to you all!
regards
angelo
After 10 hours of "warming up" leading to a serious listening session, I can say that converter with the PCM1798 module (outputs directly to transformers) represents a step over the CS4398. The sound is "richer" and "warmer". More analog I should say. Some new informations in the soundstage bring a nice touch of realism to the music (for exemple, a recording of choir in a cathedral gives now plenty of echoes).
Follow-up: PCM1798
Ref. post 2129
I tried 200R instead of 100R and the output level is much better. Could live with that.
Ref. post 2129
I tried 200R instead of 100R and the output level is much better. Could live with that.
I've been running this dac a while now using Tamura 80800s on the outputs, thanks go to hoverdonkey for getting me started.
Primary and secondary loading are shown in the pic.
I'm finding the presentation a little restrained. Can anyone give me a steer on getting a little more forward presentation without putting my speakers at risk?
Many thanks
Primary and secondary loading are shown in the pic.
I'm finding the presentation a little restrained. Can anyone give me a steer on getting a little more forward presentation without putting my speakers at risk?
Many thanks
Attachments
I am using Lundahls trafos,and I to think it sounds a bit restrained.I don´t use the cap and resistor on the sec. and not the cap on the prim.But I do use the resistors on prim.
And I wonder is this resistors necessery?What are they for?Maybe I can try without them?
I'm curious about this as well.
The cap/resistor on the secondary are a low pass filter to get rid of the digital to analog artifacts. But the transformer itself has limited bandwidth, so they may be unnecessary.
I don't know the purpose of the cap on the primary.
The resistors on the primary are there to keep the load from being too low on the DAC. But a previous post in the thread mentions that the load attached to the secondary is seen by the DAC and you actually want a parallel resistor to lower the impedance seen by the DAC. This is what is confusing me.
NO !!!
The cap/resistor on the PRIMARY are a low pass filter (~150khz) to get rid of the digital to analog artifacts
The cap/resistor on the secondary are a anti-ringing filter, the values depends on the transformers characteristics , above 80 khz
R.C.
DAC new R-core power transformer
What about the new R-core power transformer offered with this kit. Claims to sound better than toroidal pwr xfmrs. Although it looks like it's made of taffy, lol.
I like the idea of separate primary/secondary bobbins. Anyone tried it?
What about the new R-core power transformer offered with this kit. Claims to sound better than toroidal pwr xfmrs. Although it looks like it's made of taffy, lol.
I like the idea of separate primary/secondary bobbins. Anyone tried it?
This is not correct: the windings are distributed on both bobbins.
I cannot recognize, that this trannies are tested for a 4kV isolation, how it should be for safety reason.
I used some of the R-cores in the past and had no problem with the lower voltage versions like this one.
I had one high voltage version (for tubes) that was humming loud. Purchased one year before use, so I could not complain anymore 🙁
Imho, the main advantage of this trannies are very low production costs.
First, they bend the core, then they attach the bobbins to the core. The bobbins are directly driven to turn and apply the windings directly.
Then, the different windings are connected between the two bobbins and "molded" in a sticky honeylike material between different layers of paper and plastic foil.
Better buy a local quality product, be on the safe side and save shipping costs because of the weight.
My two cents
Franz
Mine is coming with the R core tranny...
It seems like a better option than a toroidal, but is it better than an old school tranny? Who knows.
I'm sure it will sound as good if not better than my Aragon D2A!
I'm using one(9V) on my CS4398 and while it may be quieter, soundwise, it doesn't appear to be any better/worse than the 10V Edcor EI that I was using before - at least not to my 54 year old ears. In the past I compared EIs with torroids and found the latter to have more weight and depth but then again I couldn't swear to that.
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Received my parts yesterday. Everything looks good!
Any new news on output transformers?
Looking for great sonics at a great price.
Board is smaller than I envisioned, so a fairly small enclosure is needed. Maybe I'll make a single 19" wide face plate with two separate enclosures behind it...😕 Could be cool, and keep the A/C transformer away from everything else.
Anyway, wish me luck!😉
Any new news on output transformers?
Looking for great sonics at a great price.
Board is smaller than I envisioned, so a fairly small enclosure is needed. Maybe I'll make a single 19" wide face plate with two separate enclosures behind it...😕 Could be cool, and keep the A/C transformer away from everything else.
Anyway, wish me luck!😉