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Post by Deleted on Feb 14, 2011 2:53:35 GMT
DREAM ON !   P.S. I am now using a Paul Hynes 3.3V 150mA shunt in the Input PCB for the DIR9001 etc. |
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XTRProf
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Post by XTRProf on Feb 14, 2011 3:33:06 GMT
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Post by Deleted on Feb 14, 2011 4:03:59 GMT
DREAM ON ! P.S. I am now using a Paul Hynes 3.3V 150mA shunt in the Input PCB for the DIR9001 etc. Wait till I had Paul Hynes or similar the X-Dac V3 and also the super clock as well with separate PSs! Well, you had better remove all that crap you did originally then, and take a leaf out of Rob's and my book ! Rob has essentially done quite similar to what I did, but taken it further, where I didn't go because of the need to fit it all in a much bigger case, and heaps more expense.In it's present form it sits nicely on my PC desk. The X-DAC V3 is my secondary DAC ! |
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XTRProf
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Post by XTRProf on Feb 14, 2011 7:58:02 GMT
Well, you had better remove all that crap you did originally then, and take a leaf out of Rob's and my book ! Rob has essentially done quite similar to what I did, but taken it further, where I didn't go because of the need to fit it all in a much bigger case, and heaps more expense.In it's present form it sits nicely on my PC desk. The X-DAC V3 is my secondary DAC ! Oh, don't need to. Just need to enhance it with what Rob had done which in the first place some years back you said would not be much improvement with more toroids and super regulators and with a superclock. Only recently then you concur. That's the reason why your X-Dac V3 is a second dac on the PC Desk whereas mine is in the main rig. Rob also agreed that the X-Dac V3 properly moded will be VERY VERY SUBSTANTIAL. Looking at the DAC chip I found that the chip in my X-DAC has a better S/N ratio, and further not much different. Why then the claim that the SC DAC sounds so much better? So I chose to hook everything in my X-DAX up to separate shunt regulated power supplies with separate torroids. 1x-15-0+15 for the opamps, one 5.5 volt for the analog part of the dac chip, one 5v for the digital part and one 3.3 for the the I/O board (yes, 4 regulators + 4 torroids). I restored the opamp rails back to 15V, and lowered the 2 100uF elco's to 36. (I used the twisted pear Placids for shunt regulators) I would say the improvement is VERY, VERY substantial. |
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Post by Deleted on Feb 14, 2011 8:25:49 GMT
Chong
Seeing that your modified version of the X-DAC V3 is performing so well, why don't you post some internal photos, and give others further information about the improvements you have made ?
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Post by robvanaalst on Feb 16, 2011 0:07:49 GMT
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Post by Deleted on Feb 16, 2011 0:25:02 GMT
Hi Rob
The main reason I didn't go as far as you have with the X-DAC V3 is the need for a larger case to accomodate it all. Hence my decision to buy the SC DAC kit which has many similarities circuit wise, but plenty of room in the 1U rack case. Besides which, I needed another DAC for use in the main system
As I have a reasonable supply of JLH PCBs, it also made sense for me to use JLHs rather than spend lots more money on commercial regulators. Initially it was clearly outperformed by the modified X-DAC V3,
until I did heaps of modifications, including the change to 1792 type output filtering.
However, things change, and recently Syd very kindly sent me a couple of Paul Hynes 150mA 3.3V shunt regulators. They further benefit from the JLH giving them a bloody good headstart !
Initially, I am using one to feed the Input PCB (DIR9001 etc.) instead of the low noise 3.3V opamp supply. ("Cricket")
Next stage will be to use another PH 3.3V series regulator to supply the digital 3.3V for the 1796.
BTW, when using the shunt regs etc. you are likely to have trouble hearing any marked difference between the 1792 and the 1796 ,which has improved specs over the 1796, unless your amplification is also extremely low noise too.
My long term plans for the SC DAC do include the possible inclusion of at least one more toroidal.
Regards
Alex
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XTRProf
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Post by XTRProf on Feb 16, 2011 1:14:41 GMT
Great! Thanks. Good to see that you had removed the AC rectifiers (AC overall) far away from the audio boards as that's the best. Only pure dc on the audio board. I will try to do that as well after some thoughts over it on how to do it nicely and practically. Also, I will think over how to do the 4 toroids + super regulators from your implementation. Again, nicely and practically.  Btw, how much you paid for the Placid super shunt regulators without having to check? |
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Post by robvanaalst on Feb 19, 2011 13:04:33 GMT
I wouldn't call it a "super shunt regulator" It's a shunt regulated power supply, nothing more, nothing less. The single rails are 40 USD and the BP is 60USD. What I like about them is that you can easily change the output voltage (5V - 15V) AND the shunted current with trim pots. The Placids are kits, so you have to built them up yourself, but the boards come with the SMD components pre-soldered. If you compare these Placids to the JHL/Jaycar PS combination, they are smaller than the combined JHL/Jaycar PS footprint, and about USD20 more expensive. In terms of quality, they outperform the JHL (I don't know about added Paul Hynes components). Here is a link to the Placid: www.twistedpearaudio.com/power/placid.aspx |
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XTRProf
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Post by XTRProf on Feb 19, 2011 13:38:56 GMT
I wouldn't call it a "super shunt regulator" It's a shunt regulated power supply, nothing more, nothing less. The single rails are 40 USD and the BP is 60USD. What I like about them is that you can easily change the output voltage (5V - 15V) AND the shunted current with trim pots. The Placids are kits, so you have to built them up yourself, but the boards come with the SMD components pre-soldered. If you compare these Placids to the JHL/Jaycar PS combination, they are smaller than the combined JHL/Jaycar PS footprint, and about USD20 more expensive. In terms of quality, they outperform the JHL (I don't know about added Paul Hynes components). Here is a link to the Placid: www.twistedpearaudio.com/power/placid.aspxHi Rob, Thanks. The prices are actually about the range of those "super" regulators that we are talking about. If they are not under "super" then it will be something like either a Sala or Cricket shunt regulator that people are using here in Rockgrotto. As I didn't follow the development of those names fully here, I may have the wrong names. Let me see your link and investigate more to see how different they are from those SRs. Paul Hynes' regulators are definitely in the super group and most well designed super regulators will outperform the JLH anytime. That's the reason I prefer super regulators implemention than the JLH in my audio projects. I also like a regulator that is variable as we are not tied down to a specific use when we don't like it any more. Most super regulators don't have it as obviously those designers want us to buy more from them to be richer. |
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Will
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Post by Will on Feb 19, 2011 16:26:30 GMT
Chong,
If you ask the manufacturer of the shunts you mention, he is more than happy to share how to change the current capability and the voltage, indeed the information is on some forums. There are very good reasons not to use a trimpot in some cases. The fact that he allows people to do this, and still supports the warranty shows how understanding of the DIY'er he is.
Also, Have you tried a JLH ripple eater, and if so, with what equipment? You seem to have dismissed it without fair trial. I've compared it to other shunts, both diy and bought, but have you? Was the difference enough that you would for-go a few CD's to buy the commercial supply? It is a consideration.
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Post by robvanaalst on Feb 19, 2011 19:07:53 GMT
Sorry - no idea "super shunt regulator" was a defined system, especially because most shunts don't come with specs, in terms of slew rate, bandwith, etc. - and if they do, like the Paul Hynes, there is no proof in terms of test set-up, or test graphs to back up these claims)
So, I have no idea if the Placid meets that "super" definition, but I hold its designer Russ White in high very high regards, and the product is not much more expensive than its components. I do know the placid outperforms the JHL in a listening test.
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Post by Deleted on Feb 19, 2011 21:14:08 GMT
Rob
I use the SC PSU and JLH in many different projects.
I can walk in and buy the PSU kits over the counter, and not order everything from the U.S.A, possibly waiting in a queue to have them made, as in the case of the PH regulators where you may wait a couple of months to have them made, then wait up to 3 more weeks to have them delivered.
I can use a standard JLH in the vast majority of my projects without making any adjustments or replacing components.It also has an optional current limiter section that does more than just provide current limiting.With amplifiers as distinct from purely digital circuits, you don't always want to use the JLH without the CL , or a super regulator/ TP Placid. The Class A HA/Preamp actually sounds better when using the CL in the JLH.
Alex
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Post by robvanaalst on Feb 20, 2011 17:48:18 GMT
Hi Alex,
One of the reasons I bought the Placids, is that I live in the USA, and buying from Jaycar takes 3 weeks, we don't have stores who readily sell comparable and cheap power supplies kits over the counter. The Placid is all in one - no need to worry about power supply boards and JHL boards and components - just a lot easier for just a bit more money.
The difference between the Placid and the Jaycar PS + JHL isn't so big that I would promote it till I drop. For me its just the combination of an all-in-one alternative that's a bit better and much easier and faster to obtain when you're living in the USA.
In your case - living in Australia - I would probably make the same choice as you did/do.
Rob
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XTRProf
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Post by XTRProf on Feb 21, 2011 3:21:34 GMT
Chong, If you ask the manufacturer of the shunts you mention, he is more than happy to share how to change the current capability and the voltage, indeed the information is on some forums. There are very good reasons not to use a trimpot in some cases. The fact that he allows people to do this, and still supports the warranty shows how understanding of the DIY'er he is. Really, that will be great! But modifying in SMDs?  Also, Have you tried a JLH ripple eater, and if so, with what equipment? You seem to have dismissed it without fair trial. I've compared it to other shunts, both diy and bought, but have you? Was the difference enough that you would for-go a few CD's to buy the commercial supply? It is a consideration. Nope, I don't dismiss anything. In fact, I will put 2 in the coming AHA build, as I had mentioned earlier, when I have the time to assemble them since I have many JLH PCBs lying around. It's just that the super regulators will be superior to the JLH and that's a fact. I will only remove the JLH when I have the doe and time to super regulate the AHA. Fyi.  |
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Will
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Post by Will on Feb 21, 2011 18:43:51 GMT
Ah! I'm glad you are going to try them out, as it's quite worth it. The class A without at least a JLH is like a massage without a happy ending |
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Post by mrarroyo on Feb 22, 2011 11:44:33 GMT
Rob, I wished I had seen the placid board earlier. I needed two power supplies one in 5V DC and the other in 12V DC to power an Squeezebox 3 and a Wadia 170i. I ended up buying the Keces PSU that will do 5/12/15V DC with two outputs at the same time. Oh and it does 2.5 amps on each output.
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Post by 31mohan on Mar 3, 2011 18:11:15 GMT
Hi Alex,
I have just assembled the X-dac outboard power supply based on Jaycar Stock kit. Kindly let me know whether this regulated power supply can be directly plugged on to X-dac V3 via a Din plug.
Why I ask this is, my power supply (wall plugged) came with the x-dac v3 seems to be a 24V AC.
When you connect the wall plug via its 3-pin din plug to x-dac V3, it seems the internal rectifier circuit of x-dac V3 converts the AC current to DC current.
In consideration of the above, can I use the newly constructed X-dac V3 mod (using Jaycar kit) via 3-pin plug? In other words, can we connect this regulated power supply with dc output to X-dac v3 via the din plug. without modifying or bypassing the internal rectifier circuits.
Kindly advise me .
Thanks
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Post by Deleted on Mar 3, 2011 20:26:43 GMT
Hi Alex, I have just assembled the X-dac outboard power supply based on Jaycar Stock kit. Kindly let me know whether this regulated power supply can be directly plugged on to X-dac V3 via a Din plug. Why I ask this is, my power supply (wall plugged) came with the x-dac v3 seems to be a 24V AC. When you connect the wall plug via its 3-pin din plug to x-dac V3, it seems the internal rectifier circuit of x-dac V3 converts the AC current to DC current. In consideration of the above, can I use the newly constructed X-dac V3 mod (using Jaycar kit) via 3-pin plug? In other words, can we connect this regulated power supply with dc output to X-dac v3 via the din plug. without modifying or bypassing the internal rectifier circuits. Kindly advise me . Thanks When using a dual regulated PSU of +-15 to +-15.5V, just ensure that 0V goes to the centre pin of the 3pin DIN plug. The internal diodes will then steer the DC correctly.I preferred to use a 30VA toroidal from Altronics, but the 20VA as supplied by Jaycar will be O.K. if you are from Downunder. Make sure that the heatsinks of the 2 voltage regulators don't run too hot.If so , you may be able to fit a mini heatsink inside the larger type to assist. Alex |
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Post by 31mohan on Mar 4, 2011 14:25:34 GMT
Dear Alex,
Thanks for your reply. As you have suggested, I have used 50VA Toroidal which I bought from Farnell.
As I am new to this mod, can I plug in this outboard regulated PSU directly to X-dac V3 without any modification to X-dac V3. In other words, can I directly plug the dc output of the MOD PSU to X-dac via DIN plug?
Please excuse me for asking this question. Secondly, you have suggested a small heat sink to be installed. Does that mean this small heat sink to be installed on the voltage regulators of the outboard (newly assembled) regulated PSU. Nothing to do with X-dac?
Kindly advise me.
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Post by 31mohan on Mar 10, 2011 1:34:59 GMT
Hi Alex,
I am eagerly waiting for your reply. I hope I am not bothering you.
Cheers
Mohan
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Post by Deleted on Mar 10, 2011 2:04:44 GMT
Dear Alex, Thanks for your reply. As you have suggested, I have used 50VA Toroidal which I bought from Farnell. As I am new to this mod, can I plug in this outboard regulated PSU directly to X-dac V3 without any modification to X-dac V3. In other words, can I directly plug the dc output of the MOD PSU to X-dac via DIN plug? Please excuse me for asking this question. Secondly, you have suggested a small heat sink to be installed. Does that mean this small heat sink to be installed on the voltage regulators of the outboard (newly assembled) regulated PSU. Nothing to do with X-dac? Kindly advise me. Mohan Sorry, but I missed this post. As I stated above, provided that the centre pin of the new PSU's DIN plug is at 0 volts,(and the +15V and -15V are connected to the outer terminals of the DIN plug) then it may be connected directly to the X-DAC V3 without any internal modifications. I was referring to the outboard PSU when I suggested that a smaller TO220 type heatsink could possibly be mounted inside the existing heatsink from the Jaycar/Altronics PSU kits to help reduce the temperature of the LM317T (only) a few more degrees. It is not mandatory though, but I am also taking into account that we have much hotter days here in summer, than places like the U.K. do. How hot the heatsinks get is also dependent on the ambient temperature. Alex |
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Post by 31mohan on Mar 12, 2011 3:09:38 GMT
Dear Alex,
Thanks a lot, everything is clear. Thank you for your support.
Cheers
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Post by sadface on Jul 14, 2012 21:54:05 GMT
Hey guys
I am in the process of building the jaycar PSU and was wondering about the significance of not putting in the two 5w resistors?
Many thanks
Sadface
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Post by Deleted on Jul 14, 2012 23:21:31 GMT
Hey guys I am in the process of building the jaycar PSU and was wondering about the significance of not putting in the two 5w resistors? Many thanks Sadface Hi Sadface It depends on what you are using the PSU for. With the Jaycar (SC ) HA, you don't need the +5V rail,and both supply rails have fairly similar loads, so you can leave out both 5W resistors. With the X-DAC V3, the +15V supply rail is more heavily loaded, so it is best to leave the 330 ohm PW5 in to equalise loads on both supply rails, so that they decay at roughly the same rate when you switch off. As with the SC HA,the +5V rail is not required,so you can leave out the 7805 and the 100 ohm 5W. If you replace the 100 ohm 5W with a much higher value resistor, such as 22 Kohm, and fit a strap to bypass the missing 7805, you can then use that terminal block to supply something like a front panel Blue LED. Regards Alex |
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