Konnichiwa,
You mean the one I have been advocating the the late 90's for DAC's of that type?
Well, SOME Players have the SPECIFIC DAC Chips (single ended voltage output) that are suitable. Most do not. Especially, ALL the DAC's where this mod is applicable are pretty much the lowest cheap'n'nasty sort of chip, on the very bottom run of DAC's and allways a variety of the Bitstream principle and I have so far failed to appreciate the sound ANY of these DAC's makes.
Secondly, the main disadvantage is that such DAC's put out only around 1V RMS, which 6db beloe the nomral level and that they have limited ability to drive Cables and low impedance loads. But 1m of normal cable and a 10K load will be fine for any of them, so in most systems there will be no issue.
The DAC alone is not. For the kind of Chip used in the Cheapo Tosh and similar DAC's you actually have several blocks of circuitry on one chip. In a high performance digital system you often have a dedicated DSP Chip as oversampling Filter, A DAC (often per channel) and some form of analogue stage, either I/V for multibit DAC's and/or a balanced to SE cconverter.
The ultra cheap DAC chips integrate the Digital filter, the actual DAC and (part of) the analogue stage including some REALLY NASTY C-Mos Op-Amp's all on one chip, with plenty of noise feedthrough and other problems.
So it is not the DAC slone driving the Preamp, it is merely that parts of the Circuit normally seperate from the DAC have been placed on-chip to make implementation very cheap.
Sayonara
DIAR said:
You mean the one I have been advocating the the late 90's for DAC's of that type?
DIAR said:
Well, SOME Players have the SPECIFIC DAC Chips (single ended voltage output) that are suitable. Most do not. Especially, ALL the DAC's where this mod is applicable are pretty much the lowest cheap'n'nasty sort of chip, on the very bottom run of DAC's and allways a variety of the Bitstream principle and I have so far failed to appreciate the sound ANY of these DAC's makes.
Secondly, the main disadvantage is that such DAC's put out only around 1V RMS, which 6db beloe the nomral level and that they have limited ability to drive Cables and low impedance loads. But 1m of normal cable and a 10K load will be fine for any of them, so in most systems there will be no issue.
DIAR said:
The DAC alone is not. For the kind of Chip used in the Cheapo Tosh and similar DAC's you actually have several blocks of circuitry on one chip. In a high performance digital system you often have a dedicated DSP Chip as oversampling Filter, A DAC (often per channel) and some form of analogue stage, either I/V for multibit DAC's and/or a balanced to SE cconverter.
The ultra cheap DAC chips integrate the Digital filter, the actual DAC and (part of) the analogue stage including some REALLY NASTY C-Mos Op-Amp's all on one chip, with plenty of noise feedthrough and other problems.
So it is not the DAC slone driving the Preamp, it is merely that parts of the Circuit normally seperate from the DAC have been placed on-chip to make implementation very cheap.
Sayonara
.
Even for diffiential out dac, as long as it is voltage out, you can use a line output transformer to convert balance to single and directly drive a preamp.
BTW, those cheap fool-proof delta-sigma dac doesn't really sound that bad when used in direct out, even compare to the famed TDA1541 ... or it could be my hearing?
I think with those type of dac, you can have the shortest signal path possible: Dac => LM3875 => speaker.
The cheapo BB dac in the Toshiba 3950 sounds pretty good in this config.
BTW, those cheap fool-proof delta-sigma dac doesn't really sound that bad when used in direct out, even compare to the famed TDA1541 ... or it could be my hearing?
I think with those type of dac, you can have the shortest signal path possible: Dac => LM3875 => speaker.
The cheapo BB dac in the Toshiba 3950 sounds pretty good in this config.
Konnichiwa,
BEWARE, some of the earlier buffer-less differential Output DAC's do not tolerate line transformers.
In sort, the exact configuration that is best depends upon the DAC and needs to be determined according to the DAC's datasheet, a carefull reading of which is needed.
Well, I am not sure what you are comparing how and to what....
The TDA1541 has a lot of potential but is not easily implemented correctly.
Those of the BB DAC's that are in effect linear development from the PCM1710 (main architecture is identical) have invariably a certain sameness to the sound and one that to my ears is highly objectional. Their analogs from Philips and AD are not that much different either.
Hey, the bedroom system I'm using (C37 modded ultra cheap Goodmans compact stereo and 6.5" Alnico Fullrange drivers in sealed boxes, also C37) sounds "pretty good". That is untill you compare it to the big rig....
Sayonara
ChuckT said:
BEWARE, some of the earlier buffer-less differential Output DAC's do not tolerate line transformers.
In sort, the exact configuration that is best depends upon the DAC and needs to be determined according to the DAC's datasheet, a carefull reading of which is needed.
ChuckT said:
Well, I am not sure what you are comparing how and to what....
The TDA1541 has a lot of potential but is not easily implemented correctly.
Those of the BB DAC's that are in effect linear development from the PCM1710 (main architecture is identical) have invariably a certain sameness to the sound and one that to my ears is highly objectional. Their analogs from Philips and AD are not that much different either.
ChuckT said:
Hey, the bedroom system I'm using (C37 modded ultra cheap Goodmans compact stereo and 6.5" Alnico Fullrange drivers in sealed boxes, also C37) sounds "pretty good". That is untill you compare it to the big rig....
Sayonara
On the subject of DAC Chips the BB PCM1793 has Balanced voltage outputs. what is your guys view of this Chip TIA
http://focus.ti.com/lit/ds/symlink/pcm1793.pdf
http://focus.ti.com/lit/ds/symlink/pcm1793.pdf
Yes, and I have heard, that there is also a version for +/-15 until 22V.
Who know the associated type number?
Thank you for this URLEarlier I stated that SO - DIL adapters where available in Sweden from Elfa. This is not the case. They have either discontinued this product or I was mistaken and mixed it up with an experimental adapter for up to 28-pin SO. This adapter is not very practical.
Sorry for any inconvenience this may have caused.
I found a source in the USA:
http://cimarrontechnology.com/
They specialize in component adaptors.
Check the Audio Upgrade adaptors.
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