No....its not the same chip.
The main advantage of using the CS chip is that you can choose an external clock within the DAC.
With the DIR, its a better chip but you can only use the SPDIF recovered clock.
There are advantages either way. You can buy and adapter kit on ebay to utilise the DIR on a pin connection for the CS chip.
With respect to SPDIF jitter, yes it can be a problem but I
ok and here's the whole message!!! I really shouldn't post at 11:00 GMT!!!
No....its not the same chip. The main advantage of using the CS chip is that you can choose an external clock within the DAC. With the DIR, its a better chip but you can only use the SPDIF recovered clock. There are advantages either way. You can buy and adapter kit on ebay to utilise the DIR on a pin connection for the CS chip. With respect to SPDIF jitter, yes it can be a problem but I've never seen anyone argue the case for SPDIF properly. IMHO if you use the best PSU and regulation for the device generating the SPDIF and a high quality clock with its own PSU and do exactly the same at the receiver end, you will end up with something that to a very large extent flies in that face of those who dont like SPDIF. I have spent considerable time and effort messing with I2S and SPDIF. Personally, I would choose SPDIF every time with the right PSU's for digital connectivity between separate devices. However, if you were to add a USB receiver internal to a DAC or CDP, I'd not convert to SPDIF and back, I'd you the 3 internal bus lines of I2S (or similer). The only time you may have a problem is if there are differing clock speeds. With modern chips, its fairly common to run at 24.xxMhz so this makes interfacing easy. With older chips like the TDA, they run 11.xxxMhz so interfacing to a moder USB receiver would be problematic. SPDIF will overcome this at the clost of converstion (twice) and therefore the cost of multiple PSU's and clocks
ok and here's the whole message!!! I really shouldn't post at 11:00 GMT!!!
No....its not the same chip. The main advantage of using the CS chip is that you can choose an external clock within the DAC. With the DIR, its a better chip but you can only use the SPDIF recovered clock. There are advantages either way. You can buy and adapter kit on ebay to utilise the DIR on a pin connection for the CS chip. With respect to SPDIF jitter, yes it can be a problem but I've never seen anyone argue the case for SPDIF properly. IMHO if you use the best PSU and regulation for the device generating the SPDIF and a high quality clock with its own PSU and do exactly the same at the receiver end, you will end up with something that to a very large extent flies in that face of those who dont like SPDIF. I have spent considerable time and effort messing with I2S and SPDIF. Personally, I would choose SPDIF every time with the right PSU's for digital connectivity between separate devices. However, if you were to add a USB receiver internal to a DAC or CDP, I'd not convert to SPDIF and back, I'd you the 3 internal bus lines of I2S (or similer). The only time you may have a problem is if there are differing clock speeds. With modern chips, its fairly common to run at 24.xxMhz so this makes interfacing easy. With older chips like the TDA, they run 11.xxxMhz so interfacing to a moder USB receiver would be problematic. SPDIF will overcome this at the clost of converstion (twice) and therefore the cost of multiple PSU's and clocks
As previously stated, the DAC would be for my PC, with an USB-spdif converter between.
And there's atleast one month until I'll get to buy any components for the PCB...
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Grab a copy of the 1st dac circuit diagram along with the data sheets for the 3 chips. You'll be able to see how they connect and learn about the relationships between the clocks on the I2S.
I've looked at that 2nd DAC a couple of times. It would be possible to fit an external clock to the CS chip but you will need to adjust the pin that tells the chip you are using an external clock.
I've looked at that 2nd DAC a couple of times. It would be possible to fit an external clock to the CS chip but you will need to adjust the pin that tells the chip you are using an external clock.
I'll build the first one, with recommended BOM with possible exceptions for better caps etc.
Didn't know any of this.....sorry
Well now you know, dont do it again LOL!!!!
I only found out when I tried to externally clock one of the DAC's I built using a DIR chip. I have a CS8412 on the DIP through hole format (as opposed to the SMT one on an adapter) I got it from John Paul here on the forum. I've not tried it yet but this is supposed to the be the better format too.
While we are talking I2S, my current cdp has some very interesting stuff going on in the filter. STARS processing which is a filter designed for AudioAero by Anagram technologies. This sits in line on the I2S bus the same place as the digital filter (7220) in these players. I'd love to borrow the filter section and try it in something else!!
They still use this type of filter in their current player! well that, a decent clock and a VRDS transport. All that for $30k You wont learn anything just copying!!!
Well now you know, dont do it again LOL!!!!
I only found out when I tried to externally clock one of the DAC's I built using a DIR chip. I have a CS8412 on the DIP through hole format (as opposed to the SMT one on an adapter) I got it from John Paul here on the forum. I've not tried it yet but this is supposed to the be the better format too.
While we are talking I2S, my current cdp has some very interesting stuff going on in the filter. STARS processing which is a filter designed for AudioAero by Anagram technologies. This sits in line on the I2S bus the same place as the digital filter (7220) in these players. I'd love to borrow the filter section and try it in something else!!
You wont learn anything just copying!!!
That might be the case, but I'll get decent if not great sound from my PC
Don't get me wrong, I am reading up on stuff as much as time allows
You did, its the player thats now on my Avatar.
There is something very special going on with that filter for sure. The sound is very layered. I'd say the soundstage is taller than the philips which will be to do with recovered detail.
I've made some adjustments
volume control has been bypassed, the I/V opamps are swapped to LME49720MA and decouple with BG's. Main Analogoue rails have Audio Upgrades ( Fidelityaudio.co.uk ) SI smoothers, there are a sprinkling of other cap changes and a reg on the clock. Finally, I changed the valves and replaced the hovland MKP's with Mundorf supreme (much better than SE mods that are authorised AE upgrades)To be honest, i'd love to put regs everywhere!!! The SMT nature of the main board makes it difficult to work with but I do have plans!!
THe CD Pro mech has nothing other than the PSU caps changed so far. This needs clocking and a few other bits doing. I have major plans for the DAC section after the STARS filter. I have started to design another DAC section to accept the I2S from the filter. The main reason for this is that I thought that this was the board that uses the PCM1702 when I purchased it but it actuially uses the AD1853. Its seems its the Capitole Reference that uses the 1702!
Here's the board so far!
its still incomplete and I have an idea that I'll swap the audio path to the bottom layer and PSU's to the top in the final version. There are also a couple of mistakes that need sorting!!!
Funny that even in that area of the market, there is still a list as long as your arm that I would do differently!!!!
Replacing the bipolar electrolytes with 4,7uF MKP's was quite the improvement
This old CD-player is amazing in what it gives with, so far, very modest modifications.
I expect the rest of the parts for the TPR(the one for the SAA7220).
I'll order the clock etc tonight (or as soon as my banktransfer to paypal gets through), but I'll have to wait a while for the clock etc to arrive due to the hollidays.
This old CD-player is amazing in what it gives with, so far, very modest modifications.
I expect the rest of the parts for the TPR(the one for the SAA7220).
I'll order the clock etc tonight (or as soon as my banktransfer to paypal gets through), but I'll have to wait a while for the clock etc to arrive due to the hollidays.
yep....note to self......Elco's in the signal path are sh
Now look in your speaker xovers and apply the same principle!
True!
I have only PIO's in my x-overs
Diy dipoles:
15" Dayton IB
7" Dayton reference
B&G NEO8
yep....note to self......Elco's in the signal path are sh
Now look in your speaker xovers and apply the same principle!
Pic xovers(and no, the dipoles still haven't gotten a nice finish lol)
Wiring is 4x0,6mm 99,99% silverwire in PTFE tubing.
Mid-treble part
Dayton 15" IB w heavy cementblock on top
Looks are...nasty, but they sound amazing!
Well, it looks like my diy budget for the next month or two is gone.
My 9-year old apbt b*tch needs to go to the vet again, second time in 2 months.
Not really a sacrifice since I love her to bits, just letting you know the mods, builds etc might take time and I probably won't update threads as often.
My 9-year old apbt b*tch needs to go to the vet again, second time in 2 months.
Not really a sacrifice since I love her to bits, just letting you know the mods, builds etc might take time and I probably won't update threads as often.
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