This is getting circular. I've said several times I can't hear it. I'm just looking for an explanation as to why the voltage should be consistently lower on the left channel. It's nothing to do with transformers or capacitors. Just looking for the reason for the phenomenon.
What you hear is the AC signal, not the DC bias. If for some reason you do have an imbalance between the two channels, it's not related to the DC bias.
I have already mentioned how bias current of the DAC chip and the load resistor define DC voltage.
How do you block the DC from the DDDAC output? If you do not block it at all, the DC might saturate the input of your (pre)amp in some way, leading to all kinds of unexpected behaviour.
Hi,
After reading through this hundreds of pages, let me say thank you for these many ideas I got during reading.
As I just finished my rebuild, I‘d like to show you my setup: 2 Boards, DANTE supplies the i2s, regulated by Bellesons for 12V and 3.3V for the DANTE module.
Hope you like it, I love the sound!
BR
After reading through this hundreds of pages, let me say thank you for these many ideas I got during reading.
As I just finished my rebuild, I‘d like to show you my setup: 2 Boards, DANTE supplies the i2s, regulated by Bellesons for 12V and 3.3V for the DANTE module.
Hope you like it, I love the sound!
BR
Attachments
welcome to the ever growing community of DDDAC user
Nice to hear you enjoy the DAC
some music sounds out of phase ?!
Something funny going on here but unable to find the aswer to the problem.
95% of my music sounds great but some of them seem out of phase
For example;
Tears for Fears: Raoul and the kings of Spain: Humdrum and Humble.....
This track begins with a rhythm guitar lick from left to right.
It begins left but when it should go to the right it fades kinda in the backround.
Lee Ritenour: 6 string theory: '68'
3 guitar players soloing one after the other...
The first 2 sound great but the third player sound faded in the backround...
I have checked everything over and over but i cannot find the problem....
Anyone have a clue
Something funny going on here but unable to find the aswer to the problem.
95% of my music sounds great but some of them seem out of phase
For example;
Tears for Fears: Raoul and the kings of Spain: Humdrum and Humble.....
This track begins with a rhythm guitar lick from left to right.
It begins left but when it should go to the right it fades kinda in the backround.
Lee Ritenour: 6 string theory: '68'
3 guitar players soloing one after the other...
The first 2 sound great but the third player sound faded in the backround...
I have checked everything over and over but i cannot find the problem....
Anyone have a clue
Something funny going on here but unable to find the aswer to the problem.
95% of my music sounds great but some of them seem out of phase
For example;
Tears for Fears: Raoul and the kings of Spain: Humdrum and Humble.....
This track begins with a rhythm guitar lick from left to righjt.
It begins left but when it should go to the right it fades kinda in the backround.
Lee Ritenour: 6 string theory: '68'
3 guitar players soloing one after the other...
The first 2 sound great but the third player sound faded in the backround...
I have checked everything over and over but i cannot find the problem....
Anyone have a clue
Sounds like one channel is reversed in phase. Quick check with reversing one speaker polarity and listen again
Intriguing.... can you give the full name of title, album and artists, so I can check for these tracks and listen myself if this can be reproduced ?
Hi Fellow-DAC-Builders...
I build my first DDDac about 6 month ago and to my own surprise, it actually worked 100% at my first attempt
It's using a Raspberry Pi 2b with KALI as the I2S-source and a pair of Mundorf EVO Oil caps I had in stock. It uses one 5v and one 12V standard DDDac PSU's for the Kali and DDDac mainboard and another regulated 5V PSU for the Pi.
Sound wonderfully but I feel its soon time for the next step.
The question now is which road I should take. I know there really is no consensus among you about this question, but would like to hear some good arguments for you preferred solution
BTW! My tube preamp is only Single Ended...
1. Pair of Cinemag CMLI-600/600C transformers apx. € 249
2. Better caps like Jupiter Copper foil (2.2uF/100V) apx. € 220
3. A Broskie Cathode Follower tube buffer + 2 Jupiter 1uF/100V apx. € 262 (+ PSU and new case)
4. Another DDDac-board apx. € 159
I have a feeling that most of you will say..."Go for the transformers". Am I wrong here?
Not quite sure why but I have strong feelings for the BCF-buffer solution. Maybe because I think it could be fun to play around with tubes...but I would then also need a new chassis!!!
Please ignore the question if you are all tired of answering this yet again. I have read a large part of the thread...but not all of it.
Regards
Martin R.
I build my first DDDac about 6 month ago and to my own surprise, it actually worked 100% at my first attempt
It's using a Raspberry Pi 2b with KALI as the I2S-source and a pair of Mundorf EVO Oil caps I had in stock. It uses one 5v and one 12V standard DDDac PSU's for the Kali and DDDac mainboard and another regulated 5V PSU for the Pi.
Sound wonderfully but I feel its soon time for the next step.
The question now is which road I should take. I know there really is no consensus among you about this question, but would like to hear some good arguments for you preferred solution
BTW! My tube preamp is only Single Ended...
1. Pair of Cinemag CMLI-600/600C transformers apx. € 249
2. Better caps like Jupiter Copper foil (2.2uF/100V) apx. € 220
3. A Broskie Cathode Follower tube buffer + 2 Jupiter 1uF/100V apx. € 262 (+ PSU and new case)
4. Another DDDac-board apx. € 159
I have a feeling that most of you will say..."Go for the transformers". Am I wrong here?
Not quite sure why but I have strong feelings for the BCF-buffer solution. Maybe because I think it could be fun to play around with tubes...but I would then also need a new chassis!!!
Please ignore the question if you are all tired of answering this yet again. I have read a large part of the thread...but not all of it.
Regards
Martin R.
Hi Doede,
Artist: Tears for Fears
Album: Raoul and the kings of Spain (wav file)
Track: Humdrum and humble
Artist: Lee Ritenour
Album: 6 string theory (flac file)
Track: '68'
What sound different/funny?
Tears for Fears: track begins with a rhythm guitar flowing from one channel to the other. With me it starts at one channel and fades to the backround when it should flow to the other channel.....
Lee Ritenour: 3 guitarists playing continuously one at a time. First part by Steve Lukather sounds fine, second part by Neal Schon sounds faded in the backround, third part by Slash sounds fine again. Every time the second player is faded to the backround.
Some tracks have this strange fenomenon others don't
it doesn't matter if it's flac, wav or ape. Most of my collection sounds great and doesn't seem affected.
Thanks for checking Doede
@mroerup;
First: buy more DDdac decks, one is good, 2 is better, 4 is great. You get the picture
(4 Tent decks is the max with a stock DDpsu)Second: Cinemags CMLI 600/600!
Third: buy the ALLO ISOLATOR, the old version, NOT the 1.2!
This HAT sits on top of your Pi and under the KALI, it's a galvanic isolator which eliminates all noise comming from the Pi.
KALI feeds power to clean part of ISOLATOR, Pi feeds the other side of ISOLATOR.
No need to feed a Pi with "clean" power, use the stock psu that came with it.
What software are you running on your Pi?
Cheers, Paulus
Hi Fellow-DAC-Builders...
I build my first DDDac about 6 month ago and to my own surprise, it actually worked 100% at my first attempt
It's using a Raspberry Pi 2b with KALI as the I2S-source and a pair of Mundorf EVO Oil caps I had in stock. It uses one 5v and one 12V standard DDDac PSU's for the Kali and DDDac mainboard and another regulated 5V PSU for the Pi.
Sound wonderfully but I feel its soon time for the next step.
The question now is which road I should take. I know there really is no consensus among you about this question, but would like to hear some good arguments for you preferred solution
BTW! My tube preamp is only Single Ended...
1. Pair of Cinemag CMLI-600/600C transformers apx. € 249
2. Better caps like Jupiter Copper foil (2.2uF/100V) apx. € 220
3. A Broskie Cathode Follower tube buffer + 2 Jupiter 1uF/100V apx. € 262 (+ PSU and new case)
4. Another DDDac-board apx. € 159
I have a feeling that most of you will say..."Go for the transformers". Am I wrong here?
Not quite sure why but I have strong feelings for the BCF-buffer solution. Maybe because I think it could be fun to play around with tubes...but I would then also need a new chassis!!!
Please ignore the question if you are all tired of answering this yet again. I have read a large part of the thread...but not all of it.
Regards
Martin R.
I use Sowters volume control transformers (passive preamp) instead of Cinemags. This step alone makes all the difference in the world in sound quality. You can skip blocking caps also in the amp input stage, as transformers are the best security against DC offset. And of course I can skip all the electronic cirquity of preamp. I don't want to argue with people here doing this statement, of course they have their opinions/experiences (or not) but in my humble opinion these transformers better any even the best preamp out there.
Regards
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I can confirm that - As you all (maybe) know I use the specially designed for DDDAC Sowter transformers with 18 secondary taps instead of the normal 2 wire output. This is basically my "pre" amplifier - I made an Arduino controlled volume control with 18 small signal relais selecting the volume taps. (with an Apple remote control
)
I can confirm that - As you all (maybe) know I use the specially designed for DDDAC Sowter transformers with 18 secondary taps instead of the normal 2 wire output. This is basically my "pre" amplifier - I made an Arduino controlled volume control with 18 small signal relais selecting the volume taps. (with an Apple remote control
here are two pictures - It is the green PCB. The Arduino board is piggy backed on it, but it is at the other side of the pcb, so you cannot see it here
Attachments
Doede, thank you for showing us the transformer configuration. Is there any gain with this setup? I need gain in my system. One of the tube amps I am using is a low gain power amplifier that needs up to 3.5vrms for full output.
I have recently upgraded my speakers to something with much more resolution and I am now really appreciating the fine sound of the DDDAC. I also installed .0068uf polystyrene capacitors across the output resistors (single board setup) In my system this seemed to increase fluidity a bit. I generally run Pure Music in “Classic NOS Upsample” mode at 176khz which sounds the best to me.
I have recently upgraded my speakers to something with much more resolution and I am now really appreciating the fine sound of the DDDAC. I also installed .0068uf polystyrene capacitors across the output resistors (single board setup) In my system this seemed to increase fluidity a bit. I generally run Pure Music in “Classic NOS Upsample” mode at 176khz which sounds the best to me.
With this transformer I have 3,8V RMS eff. at the DAC output at the 0dB tap ….
here are two pictures - It is the green PCB. The Arduino board is piggy backed on it, but it is at the other side of the pcb, so you cannot see it here
What's the cable (flat ribbon) between the WaveIO and your volume control?
Apart from that I can confirm that the Sowter TVCs are superb with the DDDAC. I use the standard Sowter 9335 transformers in both my DDDAC builds.
That is where normally the status LEDs are connected.
I read this status in the arduino and show it in via a lookup table in software normal text on the LCD display
I can confirm that - As you all (maybe) know I use the specially designed for DDDAC Sowter transformers with 18 secondary taps instead of the normal 2 wire output. This is basically my "pre" amplifier - I made an Arduino controlled volume control with 18 small signal relais selecting the volume taps. (with an Apple remote control
Q1. Will using the Sowters force me to chuck out my tube pre amp? I mean is it necessary to remove the preamp when Sowters have been introduced or can I still retain the preamp despite getting these transformers in? I think preamp can still stay as I use my preamp still when I use Cinemags. Best if you can confirm.
Q2. I use the cinemags but still operate in the single ended mode as my amps are not built to accept balanced inputs. I still get 2.7Vrms. Would this voltage go up if I were to change the transformers to Sowters? I am relating this voltage with the overall gain/loudness that the dac carries. Is that understanding correct?
Sure, you can keep the tube pre with the TVCs. But what would be the purpose of using a TVC and a preamp? Need to switch between different inputs? You could use the TVC after the input selector.
The input of the (pre) amplifier does not need to be "balanced". I use all my DDDACs with transformer outputs, and they are all connected to amps with unbalanced inputs. The advantage of using a transformer at the DDDAC output is that it can (should!) be used with the balanced outputs of the DAC chips, thus cancelling some of the harmonic distortion. If you connect the transformer to the unbalanced output, the DC across the transformer primary (2.7 V) will saturate the core of the transformer, leading to distorted output. With a bit of bad luck you may even end up with a permanently magnetized core of your transformer!
I'd suggest you rewire your Cinemags to use the balanced DDDAC outputs and use this with your tube pre amp. Check the DDDAC documentation to figure out the correct wiring.