clock buffers
Hi tubee,
Thanks for your reply [post#618]
In the test setup I didn't use differential drivers yet, as the DAC is located close to the CD player. I synchronously reclocked the I2S signals from the servo chip and used a 7 BCK delay for WS, and inverted it to adjust the sony format so it will work with the TDA1543. This setup uses a timing chain with 6BCK intervals of course.
For the octal D-I DAC I still use the DS8922 (Dual RS422 driver / receiver) as it produces better results. But I am already looking for better ones. I also used self made stranded wire twisted pair cable of about 2.5 meters long to reduce cable induced jitter. I am testing long wires to transport differential I2S because I need it later when using the mac. When only using the CD changer, I could use much shorter I2S interlinks.
As I said, the schematic diagram is a rough setup, the 74LS164 should be a 74HC(T)164 of course (the LS indication is fixed in the schematic capture program, so I have to edit this each time). Inverters.... yes I get your point, the only ones that could cause jitter are the BCK buffers for the TDA1543 clock. Both WS and DATA may contain jitter as they are not directly determining the initiation of the conversion process in the TDA1543. The timing chain only output's both delayed WS and DATA. So only the TDA1543 BCK is critical for jitter. Well then let's try a dedicated clock driver for BCK like the CDC208 or IDT74FCT807BT.
Hi tubee,
Thanks for your reply [post#618]
In the test setup I didn't use differential drivers yet, as the DAC is located close to the CD player. I synchronously reclocked the I2S signals from the servo chip and used a 7 BCK delay for WS, and inverted it to adjust the sony format so it will work with the TDA1543. This setup uses a timing chain with 6BCK intervals of course.
For the octal D-I DAC I still use the DS8922 (Dual RS422 driver / receiver) as it produces better results. But I am already looking for better ones. I also used self made stranded wire twisted pair cable of about 2.5 meters long to reduce cable induced jitter. I am testing long wires to transport differential I2S because I need it later when using the mac. When only using the CD changer, I could use much shorter I2S interlinks.
As I said, the schematic diagram is a rough setup, the 74LS164 should be a 74HC(T)164 of course (the LS indication is fixed in the schematic capture program, so I have to edit this each time). Inverters.... yes I get your point, the only ones that could cause jitter are the BCK buffers for the TDA1543 clock. Both WS and DATA may contain jitter as they are not directly determining the initiation of the conversion process in the TDA1543. The timing chain only output's both delayed WS and DATA. So only the TDA1543 BCK is critical for jitter. Well then let's try a dedicated clock driver for BCK like the CDC208 or IDT74FCT807BT.
Hi Ecdesign,
can be this something useful (putting op-amp into Class A)?
http://www.audioasylum.com/audio/tweaks/messages/130847.html
I am already confused, what DAC to make for CD-PRO2 (48fs).
Would you later can give more details about Sonic resonators?
Till now i have best results with Klangfilm fieldcoil 8" speakers in open baflle filled with fine sand. No need tweeter, crossover. Still i plan to try also Plasma tweeters.
I tried speakers with same construction alnico and field coil (elektromagnet).
It makes very big difference in sound: much clean, details, more natural, faster...
Friend will convert Lowther speakers to field coil soon, it could be interested to hear.
All the best. Bostjan
can be this something useful (putting op-amp into Class A)?
http://www.audioasylum.com/audio/tweaks/messages/130847.html
I am already confused, what DAC to make for CD-PRO2 (48fs).
Would you later can give more details about Sonic resonators?
Till now i have best results with Klangfilm fieldcoil 8" speakers in open baflle filled with fine sand. No need tweeter, crossover. Still i plan to try also Plasma tweeters.
I tried speakers with same construction alnico and field coil (elektromagnet).
It makes very big difference in sound: much clean, details, more natural, faster...
Friend will convert Lowther speakers to field coil soon, it could be interested to hear.
All the best. Bostjan
64 bit Shift Register HFE4517
Hi ecdesigns and all,
Nice to meet you, ecdesigns. I think dual 64 bit shift register HFE4517/MC14517 will help this great job more simple. Please consider the schematic below.
You can add more MC14517 and connect to Q1-Q7 of 8 bit shift register 74HC164 for more step. For example, if connect MC14517 to output Q4 of 74HC164, you will get FS/SD20, FS/SD36, FS/SD52, FS/SD68.
How do you think?
Regards,
Monsan S.
Hi ecdesigns and all,
Nice to meet you, ecdesigns. I think dual 64 bit shift register HFE4517/MC14517 will help this great job more simple. Please consider the schematic below.
You can add more MC14517 and connect to Q1-Q7 of 8 bit shift register 74HC164 for more step. For example, if connect MC14517 to output Q4 of 74HC164, you will get FS/SD20, FS/SD36, FS/SD52, FS/SD68.
How do you think?
Regards,
Monsan S.
Attachments
pulling a opamp in class A
Audio.nl gave such tips. I did it once, after different results i never tried it again. But is worth a try.
http://audio.nl/articlepic/fig4.JPG
More tips: http://audio.nl/tips.htm
Audio.nl gave such tips. I did it once, after different results i never tried it again. But is worth a try.
http://audio.nl/articlepic/fig4.JPG
More tips: http://audio.nl/tips.htm
8 X TDA1541A / 32 X TDA1543 ?
Hi tubee,
Thanks for your reply [post#623]
The clock buffer is intended to keep BCK jitter low, it can be used for both the master clock oscillator and the synchronously reclocked BCK. Every gate (inverter) adds jitter to the input signal. I have been very busy today testing all kind of buffers. The 74...08 types seem to produce the cleanest signal. Speed: LS08 / 17nS, HCT08 / 11nS, HC08 / 7ns, F08 / 4.2ns, VHC08 / 4.3ns. So the fastest types have around 4ns propagation delay, the fastest types also seem to produce the lowest jitter.
Oh yes, I also completed the 32 X TDA1543 D-I setup, I will post a photo later. My aim was to see if it could catch-up with the octal D-I DAC, using more chip's. Even with 32 chip's the Direct Interpolation works fine. It will work with 64 chip's as well, no doubt. That's about the limit as we run out of taps.
Comparison to the octal D-I DAC using the TDA1541A showed the octal D-I DAC still sounds more beautiful, especially the warm midrange and crystal clear details and lower overall distortion. So both the tube output stage (mixed mode) and low distortion DAC's are important (TDA1543 has about 10 times higher distortion when compared to the TDA1541A). It's doubtful if the low distortion of the octal TDA1541A setup can be obtained with lot's of TDA1543's in parallell. Then there is the problem of DEM clock synchronizing, this is not possible with the TDA1543.
So after a lot of experimenting and listening, the octal D-I DAC using the TDA1541A still has the best sound quality.
Now I need to get BCK jitter as low as possible AFTER the interlink. The way this is achieved will determine how the I2S interface will be constructed. Since there is no real standard for I2S connections, I plan to use a 8 way metal DIN connector / socket with screw locking mechanism and gold plated contacts. This connector can carry 4 differential signals, BCK, WS, DATA and a addittional clock signal (MCK) and has a screen connection. The quality is better than the plastic RJ45 connectors and different types of twisted pair cable (stranded wire) can be used.
Hi tubee,
Thanks for your reply [post#623]
The clock buffer is intended to keep BCK jitter low, it can be used for both the master clock oscillator and the synchronously reclocked BCK. Every gate (inverter) adds jitter to the input signal. I have been very busy today testing all kind of buffers. The 74...08 types seem to produce the cleanest signal. Speed: LS08 / 17nS, HCT08 / 11nS, HC08 / 7ns, F08 / 4.2ns, VHC08 / 4.3ns. So the fastest types have around 4ns propagation delay, the fastest types also seem to produce the lowest jitter.
Oh yes, I also completed the 32 X TDA1543 D-I setup, I will post a photo later. My aim was to see if it could catch-up with the octal D-I DAC, using more chip's. Even with 32 chip's the Direct Interpolation works fine. It will work with 64 chip's as well, no doubt. That's about the limit as we run out of taps.
Comparison to the octal D-I DAC using the TDA1541A showed the octal D-I DAC still sounds more beautiful, especially the warm midrange and crystal clear details and lower overall distortion. So both the tube output stage (mixed mode) and low distortion DAC's are important (TDA1543 has about 10 times higher distortion when compared to the TDA1541A). It's doubtful if the low distortion of the octal TDA1541A setup can be obtained with lot's of TDA1543's in parallell. Then there is the problem of DEM clock synchronizing, this is not possible with the TDA1543.
So after a lot of experimenting and listening, the octal D-I DAC using the TDA1541A still has the best sound quality.
Now I need to get BCK jitter as low as possible AFTER the interlink. The way this is achieved will determine how the I2S interface will be constructed. Since there is no real standard for I2S connections, I plan to use a 8 way metal DIN connector / socket with screw locking mechanism and gold plated contacts. This connector can carry 4 differential signals, BCK, WS, DATA and a addittional clock signal (MCK) and has a screen connection. The quality is better than the plastic RJ45 connectors and different types of twisted pair cable (stranded wire) can be used.
Selecting the DAC setup
Thanks for your tip [post#624]
I will do some experiments with putting op-amps in class A.
As noted in the previous post, the octal D-I DAC is better compared to the TDA1543 D-I setup. So I will use the existing setup with 8 X TDA1541A.
When using CD-PRO2 (48fs), there are 2 possible solutions:
1) Use a sony format timing chain module in the octal D-I DAC, the CD-PRO2 can now be directly connected to the octal D-I DAC.
2) Use the universal I2S interface, and feed the derived philips format directly to the octal D-I DAC using a philips format timing chain. The universal I2S output signals are already synchronously reclocked with the master clock, so they have low jitter.
> I think it's best to put some more information about the sonic resonators in a new thread (loudspeakers / ESLs, planars, alternative technologies section) as soon as I have got some more time. The sonic resonators are full 360 degree omnidirectional radiators with a spherical pattern, meaning there is no sweet spot as we know it, sound impression will stay exactly the same, no matter where you listen, so the "sweet spot" is all around you and even beyond the listening room. Volume can be turned all the way up without sound colouring. Distortion is so low (due to corrective mechanism), you could loose sense of volume setting, you only notice they are playing really loud when you try to talk to someone next to you and discover you have to shout so they can hear you.
Thanks for your tip [post#624]
I will do some experiments with putting op-amps in class A.
As noted in the previous post, the octal D-I DAC is better compared to the TDA1543 D-I setup. So I will use the existing setup with 8 X TDA1541A.
When using CD-PRO2 (48fs), there are 2 possible solutions:
1) Use a sony format timing chain module in the octal D-I DAC, the CD-PRO2 can now be directly connected to the octal D-I DAC.
2) Use the universal I2S interface, and feed the derived philips format directly to the octal D-I DAC using a philips format timing chain. The universal I2S output signals are already synchronously reclocked with the master clock, so they have low jitter.
> I think it's best to put some more information about the sonic resonators in a new thread (loudspeakers / ESLs, planars, alternative technologies section) as soon as I have got some more time. The sonic resonators are full 360 degree omnidirectional radiators with a spherical pattern, meaning there is no sweet spot as we know it, sound impression will stay exactly the same, no matter where you listen, so the "sweet spot" is all around you and even beyond the listening room. Volume can be turned all the way up without sound colouring. Distortion is so low (due to corrective mechanism), you could loose sense of volume setting, you only notice they are playing really loud when you try to talk to someone next to you and discover you have to shout so they can hear you.
Timing chain setups
Hi Art,
Thanks for your tip [post#625]
Smart setup, yes this would be a super solution for the timing chain. But when I looked trough the HEF4517 datasheet, it turned out maximum advised clock frequency is only 1.5...2 MHz at 5V. BCK is about 2.8 MHz, maximum propagation delay must be well within 177ns. So the HEF4517 (220-440ns @5V) is basically too slow, it might just work, but it remains very critical. Have you already tested it ? The HEF4517 power supply voltage could be raised to 15V (60-120ns) but then 19 fast level translators would be needed.
Regards,
John
Hi Art,
Thanks for your tip [post#625]
Smart setup, yes this would be a super solution for the timing chain. But when I looked trough the HEF4517 datasheet, it turned out maximum advised clock frequency is only 1.5...2 MHz at 5V. BCK is about 2.8 MHz, maximum propagation delay must be well within 177ns. So the HEF4517 (220-440ns @5V) is basically too slow, it might just work, but it remains very critical. Have you already tested it ? The HEF4517 power supply voltage could be raised to 15V (60-120ns) but then 19 fast level translators would be needed.
Regards,
John
Hi EC,
Well, I have to wonder as your Octal D-I DAC nears completion how much it will end up costing as a DIY kit. Given the amount of machining you are putting into the chassis alone - BTW, it is very professional and clean looking - plus the number of parts involved in the digital and analogue sections, I'm hoping the kit price won't sky rocket - at least by DIY standards. Could you give an estimate of what this kit is going to cost for us mortals?
Well, I have to wonder as your Octal D-I DAC nears completion how much it will end up costing as a DIY kit. Given the amount of machining you are putting into the chassis alone - BTW, it is very professional and clean looking - plus the number of parts involved in the digital and analogue sections, I'm hoping the kit price won't sky rocket - at least by DIY standards. Could you give an estimate of what this kit is going to cost for us mortals?
Hi ecdesigns,
Yes, I tested it with 2 TDA1541A and it work just fine. The Vdd for 4517 (I used MC14517 Motorola) is 7.8V and it work properly. I observed the sonic different from ordinary parallel DAC as you explained. I had design the PCB for 4 TDA1543 with DI setup by MC14517 at 10V for Vdd. Maybe, I'll report the result to you again by next month. Also, I'll increase Vdd for 4517 to 14-15V, to reduce the delay. Thank you very much for your suggestion.
Best Regards,
Monsan S.
Yes, I tested it with 2 TDA1541A and it work just fine. The Vdd for 4517 (I used MC14517 Motorola) is 7.8V and it work properly. I observed the sonic different from ordinary parallel DAC as you explained. I had design the PCB for 4 TDA1543 with DI setup by MC14517 at 10V for Vdd. Maybe, I'll report the result to you again by next month. Also, I'll increase Vdd for 4517 to 14-15V, to reduce the delay. Thank you very much for your suggestion.
Best Regards,
Monsan S.
hi monsan,
how are U. I email to U man time but hadn't received your call back. Can U call wichai email to my private email address thomas_siu@hotmail.com.
thx
thomas
how are U. I email to U man time but hadn't received your call back. Can U call wichai email to my private email address thomas_siu@hotmail.com.
thx
thomas
hi all,
I was thomas groups buy 1541a dac in groups forum. I had some 1541a S2 i taiwan will come next week.
This is money back gurantee was real chip ( TDA1541a S2). If the chips was not real. I will money back gurantee. Test with several studio monitors for the performance.
thxprice will USD 105 per one include postage ( reg.mail to oversea).
Paypal will added 1.5% charge.
USD87 per chip was the dealer price from taiwan. Now I only charge USD105 per chips for diyers include postage.
this is a good price of 1541aS2 because now the internet price was increase to USD130 per chips & not include postage.
period of the chips was 9713, 9713 period of 1541a was made for japan marantz for selection to project D7 & zandan lab 5000.
pls considerate. 3 days deadline only.
any interest ls let me know asap.
thx
thomas
I was thomas groups buy 1541a dac in groups forum. I had some 1541a S2 i taiwan will come next week.
This is money back gurantee was real chip ( TDA1541a S2). If the chips was not real. I will money back gurantee. Test with several studio monitors for the performance.
thxprice will USD 105 per one include postage ( reg.mail to oversea).
Paypal will added 1.5% charge.
USD87 per chip was the dealer price from taiwan. Now I only charge USD105 per chips for diyers include postage.
this is a good price of 1541aS2 because now the internet price was increase to USD130 per chips & not include postage.
period of the chips was 9713, 9713 period of 1541a was made for japan marantz for selection to project D7 & zandan lab 5000.
pls considerate. 3 days deadline only.
any interest ls let me know asap.
thx
thomas
Attachments
hi ErikdeBest,
actually this dac was more complicate than my design. japhn pay much more effort than me in 1541a, I would like to say. my design was use more accurate & simple design for the1541a.
For the chips, since the chips was not easy to get. Taiwan seller offer money back gurantee to me. I do the same too for more diyers. Because during in my testing , in NOS mode had quite large different between chips. I think john's will be same too.So if john's ultimate design had better chips support may be will better to performance more.
Pls check the price in internet & me. (internet is approx USD 130 per one).Chips post to me from taiwan & post to hong kong. every chip offer to me is USD87. now offer to all diyers only USD 105 include reg.mail postage to diyers. I only hope can accumulate 50 pcs of chips for this orde. otherwise the price will higher!!!!!!
pls understand.
thx
thomas
actually this dac was more complicate than my design. japhn pay much more effort than me in 1541a, I would like to say. my design was use more accurate & simple design for the1541a.
For the chips, since the chips was not easy to get. Taiwan seller offer money back gurantee to me. I do the same too for more diyers. Because during in my testing , in NOS mode had quite large different between chips. I think john's will be same too.So if john's ultimate design had better chips support may be will better to performance more.
Pls check the price in internet & me. (internet is approx USD 130 per one).Chips post to me from taiwan & post to hong kong. every chip offer to me is USD87. now offer to all diyers only USD 105 include reg.mail postage to diyers. I only hope can accumulate 50 pcs of chips for this orde. otherwise the price will higher!!!!!!
pls understand.
thx
thomas
Hi John.
Thanks for the helpful tests for most jitterfree logic for buffering. I will use these tips. I don't have good equipment for it here to test this.
I discovered also that less distorsion is very important for overall sound. (the OP2132 has only 0.0008%, the 4 transistor I/V problably a lot more) The 1541 can reach allmost PCM63 in distorsion figures. The 1543 would be a nice dac for live-like recordings and/or music.
[Btw 1: over 100 euro for a S2
]
[Btw2: i asked my friend, to join for a visit]
Thanks for the helpful tests for most jitterfree logic for buffering. I will use these tips. I don't have good equipment for it here to test this.
I discovered also that less distorsion is very important for overall sound. (the OP2132 has only 0.0008%, the 4 transistor I/V problably a lot more) The 1541 can reach allmost PCM63 in distorsion figures. The 1543 would be a nice dac for live-like recordings and/or music.
[Btw 1: over 100 euro for a S2
][Btw2: i asked my friend, to join for a visit]
hi tubee,
not over 100EURO.
USD 105 only.
.can U check your country will it cheaper??
any more source that we can order. If your source can cheaper, I guess we can arrange groups buy.
Now I hope to accumulae 50 pcs. If we can groups more. I thought I can talk the price little bit lower.
But we must accumulate more nos of chips.
thx
thomas
not over 100EURO.
USD 105 only.
.can U check your country will it cheaper??
any more source that we can order. If your source can cheaper, I guess we can arrange groups buy.
Now I hope to accumulae 50 pcs. If we can groups more. I thought I can talk the price little bit lower.
But we must accumulate more nos of chips.
thx
thomas
Hi Thomas
I know the price of the S2 are high and that you are maybe one of the last safe sources for this chip. Probably the OCTAL DAC would work wonders with the S2. Maybe the investment isn't even that bad, as people also pay the same money for a pair of NOS WE300B's or a power cord. But I, I just can't afford it with my student budget!
And..any info on the TVC's?
Erik
I know the price of the S2 are high and that you are maybe one of the last safe sources for this chip. Probably the OCTAL DAC would work wonders with the S2. Maybe the investment isn't even that bad, as people also pay the same money for a pair of NOS WE300B's or a power cord. But I, I just can't afford it with my student budget!
And..any info on the TVC's?
Erik