Hi All,
My first DAC project. Please be patient.
Bought an ebay 9028 DAC also bought Antek AS-0509 and AS-0518
How do I connect the 2 x 18V ? 18V - 0 - 18V There are two sets of Green and Blue wires.
Thank you !
- Mark
My first DAC project. Please be patient.
Bought an ebay 9028 DAC also bought Antek AS-0509 and AS-0518
How do I connect the 2 x 18V ? 18V - 0 - 18V There are two sets of Green and Blue wires.
Thank you !
- Mark
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I'd just double check that the blue and green you've got twisted together are from separate windings and assuming they are then yes you're good to go!
I'm still developing DACs based on TDA1387, have not so far found need to upgrade the DAC chip itself. Just improving the output stages but I might have now reached the end of the road for those....
I'm still developing DACs based on TDA1387, have not so far found need to upgrade the DAC chip itself. Just improving the output stages but I might have now reached the end of the road for those....
Dear abraxalito,
Thank you for the assistance !
I got the 9028 to work and within 15 minutes I am back to the TDA1387 x8. Maybe I can keep working on the 9028, but it sounds brittle and artificial to me.
The TDA1387 does not have the dynamic range or the large soundstage of the 9028, but the TDA1387 sounds musical.
Have you tried the DAC-AH DAC TDA1543 x8 ?
Hard to believe I am already giving up on the 9028.
Best,
- Mark
Thank you for the assistance !
I got the 9028 to work and within 15 minutes I am back to the TDA1387 x8. Maybe I can keep working on the 9028, but it sounds brittle and artificial to me.
The TDA1387 does not have the dynamic range or the large soundstage of the 9028, but the TDA1387 sounds musical.
Have you tried the DAC-AH DAC TDA1543 x8 ?
Hard to believe I am already giving up on the 9028.
Best,
- Mark
I'm a little surprised that the 9028 was so unsatisfying so early on. I've not heard one but from what I've read its supposed to address at least some of the weaknesses with the 9018. I would guess that the brittleness might be coming from the output stage - reading the eBay seller's page its using NE5534s. Opamps are in general a poor choice to use with the very high speed signals coming out of a DAC, but if I have to go for an opamp as I/V I'd use something JFET and high speed like AD843.
You can upgrade your TDA1387 with an anti-imaging filter, I've found a 2 inductor, 3 capacitor filter improves dynamics quite a lot when placed between DAC and an active I/V stage.
DAC-AH was my favourite DAC for quite some time, I have modified several of them. There's one in progress at the moment in fact which I'm wanting to build a high voltage output stage for so I can directly drive my 600ohm headphones with only a FET follower.
Yes I agree about the musicality of the 1387, no ESS DAC that I've heard so far has the richness of tonal colours that the 1387 can deliver in the right implementation.
You can upgrade your TDA1387 with an anti-imaging filter, I've found a 2 inductor, 3 capacitor filter improves dynamics quite a lot when placed between DAC and an active I/V stage.
DAC-AH was my favourite DAC for quite some time, I have modified several of them. There's one in progress at the moment in fact which I'm wanting to build a high voltage output stage for so I can directly drive my 600ohm headphones with only a FET follower.
Yes I agree about the musicality of the 1387, no ESS DAC that I've heard so far has the richness of tonal colours that the 1387 can deliver in the right implementation.
Dear abraxalito,
What would you suggest ? Not sure it is worth it to work on the 9028. I could replace the NE5534s with AD843s.
Or is it more worthwhile to further upgrade the TDA1387 ? (so far have swapped the opamps to AD845, and removed the 2n2 Opamp Feedback Capacitors) I looked at the anti-imaging filter and that would be beyond my capabilities.
Do you prefer the TDA1387 x8 or the DAC-AH ?
Thank you !
- Mark
p.s. I keep switching between the TDA1387 and the 9028 to make sure I am not "missing something", but I prefer the TDA1387
What would you suggest ? Not sure it is worth it to work on the 9028. I could replace the NE5534s with AD843s.
Or is it more worthwhile to further upgrade the TDA1387 ? (so far have swapped the opamps to AD845, and removed the 2n2 Opamp Feedback Capacitors) I looked at the anti-imaging filter and that would be beyond my capabilities.
Do you prefer the TDA1387 x8 or the DAC-AH ?
Thank you !
- Mark
p.s. I keep switching between the TDA1387 and the 9028 to make sure I am not "missing something", but I prefer the TDA1387
Upgrading opamps is only useful as a stop-gap measure, eventually you'll get fed up of opamp sound and want to go discrete. Once there, there's no looking back nostalgically to our 8 legged friends
First you have to decide what you want - obviously if playing hires files (>16bits) is your aim then 1387 won't be able to indulge you. But if you want to enjoy yourself on RBCD recordings then stick with 1387 and upgrade it with a filter and I/V stage. I have a newer filter design now than the one I shared on Malefoda's thread. That was a post-I/V filter but I've found better sound from putting the filter before the I/V.
If building an LC filter is beyond you then I'd suggest ditching the opamps on your 1387 DAC and fitting a single transistor I/V stage.
I don't much care for DAC-AH in stock form with its 1543s and opamp output stage. But upgraded it's a fine machine - the upgrades I've made is changing the DACs to 1387s and also, on one of them, 1545s. I've also gotten rid of the AD847s. Fitting a filter and keeping the 1543s is also a worthwhile step up.
First you have to decide what you want - obviously if playing hires files (>16bits) is your aim then 1387 won't be able to indulge you. But if you want to enjoy yourself on RBCD recordings then stick with 1387 and upgrade it with a filter and I/V stage. I have a newer filter design now than the one I shared on Malefoda's thread. That was a post-I/V filter but I've found better sound from putting the filter before the I/V.
If building an LC filter is beyond you then I'd suggest ditching the opamps on your 1387 DAC and fitting a single transistor I/V stage.
I don't much care for DAC-AH in stock form with its 1543s and opamp output stage. But upgraded it's a fine machine - the upgrades I've made is changing the DACs to 1387s and also, on one of them, 1545s. I've also gotten rid of the AD847s. Fitting a filter and keeping the 1543s is also a worthwhile step up.
Thank you abraxalito,
I have tried listening to a few high res files with the 1387, for me it seems to be more about the recording than the resolution. A good recording is a good recording.
Can the 1387 x8 work with Ian's FIFO ?
Can you point me to information about your single transistor I/V stage ? Interested to see if it is something I can build.
- Mark
I have tried listening to a few high res files with the 1387, for me it seems to be more about the recording than the resolution. A good recording is a good recording.
Can the 1387 x8 work with Ian's FIFO ?
Can you point me to information about your single transistor I/V stage ? Interested to see if it is something I can build.
- Mark
Thank you phase for the suggestion, I looked and discrete opamps seem very expensive more than the cost of the DAC. Or am I missing something ?
Prefer the TDA1387 to the TDA1543
Hi abraxalito,
Thank you for the feedback ! Seems that you prefer the TDA1387 to the TDA-1543
- Mark
Hi abraxalito,
Thank you for the feedback ! Seems that you prefer the TDA1387 to the TDA-1543
- Mark
I would guess so but I've not studied Ian's work on his FIFO as I've never found jitter to be any kind of problem with my DACs.
I've attached a hand-drawn schematic for what I mean here - its a simple common-base stage with the base reference voltage derived from a TL431 voltage reference. Nowadays I use this stage on the output of my LC filter but it can work directly connected to TDA1387s. To enhance it add current sources to both the emitter and collector of the BC807 - this lowers the input impedance. In its present form the input impedance varies rather with the current flowing through it. The I/V resistor (1k1 here) depends on the number of DACs you have paralleled - for 8 DACs as you have you need about 300ohms.
As to preferring TDA1387 to TDA1543 yes in general I do prefer the CMOS part. However the 1543 has a certain charm, a rather softer sound. I do plan to listen to the 'A' variant as it seems to have fixed at least one problem with the original part. Without the LC filter though the 1387 is a little bit 'in yer face' for me and I might well prefer the additional softness of 1543.
I've not heard of that digital power supply you mention - I will investigate it.
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Seems to me that the principle benefit of discrete opamps is they're biassed more into classA than integrated ones. But for I/V duty an opamp topology is less than ideal in my estimation - it provides the lowest possible input impedance but that's just one parameter of interest.
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