I have my DAC directly connected to my power amp (via a capacitor) without an intervening preamp unit, or a volume control of any kind. I designed the DAC to produce a fullscale signal amplitude of only 140mV RMS. The resulting loudness is usually enough to suit me. My speakers have 93dB sensitivity, and depending on the CD, can sometimes be a bit too loud, and sometimes a bit to low. However, it is a well tolerable at either of those extremes.
I have it configured this way because it gives me the most transparent, most realistically natural reproduction I've yet heard from my system. So much so that, for now, it's worth the inconvenience of having no volume control. For reference, my preamp unit was a discrete JFET unit made by the now defunct Forte' company.
I was looking at one of these, would this be any good?
Am I correct in thinking that id I run my DAC straight to power amp there is a risk I could blow my speakers if the software on my laptop crashes?
Thanks
Am I correct in thinking that id I run my DAC straight to power amp there is a risk I could blow my speakers if the software on my laptop crashes?
Thanks
DDDAC1794S Circuits (pdf)
Ooops... 😱 I promized the PDF with circuits of the DDDAC1794S...
bit forgotten... 😀
so here it is 😎
Ooops... 😱 I promized the PDF with circuits of the DDDAC1794S...
bit forgotten... 😀
so here it is 😎
Am I correct in thinking that id I run my DAC straight to power amp there is a risk I could blow my speakers if the software on my laptop crashes?
Thanks
Unlikely, ATC speakers are well designed and at 85dB sensitivity and rated at iirc about 300W yours are hefty speakers to drive. Your amp is at best 80W so it's unlikely that it would blow the speakers unless it was driven massively into clipping and left on for a while.
Thanks
Unlikely, ATC speakers are well designed and at 85dB sensitivity and rated at iirc about 300W yours are hefty speakers to drive. Your amp is at best 80W so it's unlikely that it would blow the speakers unless it was driven massively into clipping and left on for a while.
This is correct as the switch is used to logically enable or disable the drivers to allow the correct digital signals to flow to the DAC. Not sure how much you know about digital electronics but that chip has tri-state outputs so when one set of devices is disable its outputs go to a high impedance state so effectively disconnected, the other bank of gates are enabled to allow the signal through.
When you move the switch it enables the other gates and disables the current ones to allow the other input to flow to the DAC
correct, I wanted it to be simple 😀
there are three pins. The one in the middle is GND, nog you connect one of both other pins to ground via A switch and that source is selected...
Updated Circuits PDF
Did some bug fixing and updated a few textparts for, hopefully, better clarity 😱
Did some bug fixing and updated a few textparts for, hopefully, better clarity 😱
Linearity Tests
Did some linearity tests yesterday 😎
Below you see the linearity of the 8 Deck version with WaveIO input and also Spdif.
VERY good values 🙂 Nevertheless I was a bit confused on the fact the spdif kind of stopped at 20 bits 😕 Read on in the next post for this...
Did some linearity tests yesterday 😎
Below you see the linearity of the 8 Deck version with WaveIO input and also Spdif.
VERY good values 🙂 Nevertheless I was a bit confused on the fact the spdif kind of stopped at 20 bits 😕 Read on in the next post for this...
Attachments
SPDIF 20 bits max in hardware mode with WM8804
So I checked what ACTUALLY was visible on the DATA Line at the DAC Board. (See pdf file) Well, clearly to see, there are 20 bits only 😱 … So now how come that when I input 24 bits (I checked with loop-back into the AP) the WM8804 only outputs 20 bits?
I did some more in depth reading of the datasheet and found following passage (see clip PNG). This clearly states that the audio sample is 20 bits long and only if the transmitting source is defining that the auxiliary 4 bits are audio bits, they will be added to the complete word. BUT… therefore a register value must be set and this is only possible in software mode of course. No word in the datasheet that effectively in hardware mode, consequently the maximum bit depth will be 20 bits than.
I kind of stumbled over this and googling did not show up any results of any one who encountered this before. Am I the only one around here (haha sounds like 9-gag meme) who found out about this 😕 Would be interested to hear if anyone has a lead to earlier notice, similar issue with other spdif receivers or even solutions.
OK, nevertheless the 20 bits are thanks to the following 24 bit dac, linear enough up till the end. To be honest, I do not expect any audible difference versus the hypothetical software controlled version of a DDDAC1794S 😉
So I checked what ACTUALLY was visible on the DATA Line at the DAC Board. (See pdf file) Well, clearly to see, there are 20 bits only 😱 … So now how come that when I input 24 bits (I checked with loop-back into the AP) the WM8804 only outputs 20 bits?
I did some more in depth reading of the datasheet and found following passage (see clip PNG). This clearly states that the audio sample is 20 bits long and only if the transmitting source is defining that the auxiliary 4 bits are audio bits, they will be added to the complete word. BUT… therefore a register value must be set and this is only possible in software mode of course. No word in the datasheet that effectively in hardware mode, consequently the maximum bit depth will be 20 bits than.
I kind of stumbled over this and googling did not show up any results of any one who encountered this before. Am I the only one around here (haha sounds like 9-gag meme) who found out about this 😕 Would be interested to hear if anyone has a lead to earlier notice, similar issue with other spdif receivers or even solutions.
OK, nevertheless the 20 bits are thanks to the following 24 bit dac, linear enough up till the end. To be honest, I do not expect any audible difference versus the hypothetical software controlled version of a DDDAC1794S 😉
Attachments
Doede,
Have you got an estimation of when will the new mainboard becoming available?
Cheers,
Chanh
Have you got an estimation of when will the new mainboard becoming available?
Cheers,
Chanh
this is Magic 😱 I JUST sent you an email.....
the first series are almost gone ( from the 10 ) one left now.
FULL quantities expected end of February.... 🙂
Wow! Would you please resend to Chanhphotography@gmail.com? PLEASE!!
I am on vacation at this moment, previous email address used was my work email which I do not have access til Feb.
I hope you did remember me for having one reserved? Going to deposit via paypal now if you prefer?
Btw, Tuyen's DDDAC with Sowters is here with me. So amazing.......
Look forward for your email.
Chanh
I am on vacation at this moment, previous email address used was my work email which I do not have access til Feb.
I hope you did remember me for having one reserved? Going to deposit via paypal now if you prefer?
Btw, Tuyen's DDDAC with Sowters is here with me. So amazing.......
Look forward for your email.
Chanh