[bflat]

If we are discussing cost-trade off, how bad is the linear 5V power supply that comes stock on the SU-1?

 

[BlueDL]

If we are discussing cost-trade off, how bad is the linear 5V power supply that comes stock on the SU-1?

Mine came as an AC powered unit (IEC) socket and was later modified to bypass the transformer and rectifier with a 5.5mm d.c. socket in place of the IEC. So you have to buy an aftermarket 5V supply for it.

Personally, if cost was a big factor, I’d consider an iFi iPower PSU rather than use a Battery with a noisy switching output stage.

I use an Uptone LPS-1 to good effect, but it certainly dented my wallet!

 

[bflat]

Mine came as an AC powered unit (IEC) socket and was later modified to bypass the transformer and rectifier with a 5.5mm d.c. socket in place of the IEC. So you have to buy an aftermarket 5V supply for it.

Personally, if cost was a big factor, I’d consider an iFi iPower PSU rather than use a Battery with a noisy switching output stage.

I use an Uptone LPS-1 to good effect, but it certainly dented my wallet!

Right, but the built in power supply in the SU-1 is a linear power supply that transforms 120V AC to 5V DC (same thing that LPS-1 does). Should be pretty low noise on it's own. What tests have been done on a stock SU-1 to show that the built in power supply is no good or sub par?

 

[BlueDL]

Mine came as an AC powered unit (IEC) socket and was later modified to bypass the transformer and rectifier with a 5.5mm d.c. socket in place of the IEC. So you have to buy an aftermarket 5V supply for it.

Personally, if cost was a big factor, I’d consider an iFi iPower PSU rather than use a Battery with a noisy switching output stage.

I use an Uptone LPS-1 to good effect, but it certainly dented my wallet!

Thanks

Right, but the built in power supply in the SU-1 is a linear power supply that transforms 120V AC to 5V DC (same thing that LPS-1 does). Should be pretty low noise on it's own. What tests have been done on a stock SU-1 to show that the built in power supply is no good or sub par?

Yeah, sorry. I realised what you really meant after I’d posted my reply! Doh!

If you search the web, you should find a few threads on the topic. The consensus is that the stock built-in PSU is quite noisy. As such, if you are adept with a soldering iron, you can replace the 3.3V regulator chip for a very low noise option for about 40 Euros. That way you get to keep and use the front end (AC-DC conversation stage) with less of a compromise.

 

[BlueDL]

Right, but the built in power supply in the SU-1 is a linear power supply that transforms 120V AC to 5V DC (same thing that LPS-1 does). Should be pretty low noise on it's own. What tests have been done on a stock SU-1 to show that the built in power supply is no good or sub par?

This is an interesting and relevant link:

https://sparkoslabs.com/singxer-su-1-dac-ss1117-3-3v-regulator/

 

[elan120]

If you search the web, you should find a few threads on the topic. The consensus is that the stock built-in PSU is quite noisy. As such, if you are adept with a soldering iron, you can replace the 3.3V regulator chip for a very low noise option for about 40 Euros. That way you get to keep and use the front end (AC-DC conversation stage) with less of a compromise.

This is an interesting and relevant link:

https://sparkoslabs.com/singxer-su-1-dac-ss1117-3-3v-regulator/

From my experience modding SU-1, pending how far to push SU-1 for more performance, replacing this VR (3.3VDC) is one of the 5 VR's on the main board will help improve the SQ, but since this VR isn't powering any of the 3 oscillators and XMOS, replacing the other 4 VR can also help taking SU-1 to a higher level.

 

[BlueDL]

From my experience modding SU-1, pending how far to push SU-1 for more performance, replacing this VR (3.3VDC) is one of the 5 VR's on the main board will help improve the SQ, but since this VR isn't powering any of the 3 oscillators and XMOS, replacing the other 4 VR can also help taking SU-1 to a higher level.

Typically, what would such a complete overhaul of the VRs cost in total?

 

[elan120]

Typically, what would such a complete overhaul of the VRs cost in total?

I use this VR (http://www.ldovr.com/product-p/lt3045-a.htm) for the remaining 4 VR with good result. If you plan to use the same VR, you will need to specify the voltage required when ordering them.

 

[BlueDL]

I use this VR (http://www.ldovr.com/product-p/lt3045-a.htm) for the remaining 4 VR with good result. If you plan to use the same VR, you will need to specify the voltage required when ordering them.

Ok. Thanks. Probably beyond me at the moment, but I’ll bear it in mind. Maybe bflat will try this option.

 

[rafabro]

I am testing TeddyPardo VR for xmos, 5 days now and I am very happy how analog it sounds like. Also, offer better instruments color/timbre and texture than LT3045.
Very, very promising upgrade.

 

[bflat]

My SU-1 has all the VR mods plus some other internal upgrades from Kitsune Hifi. Unfortunately, I never listened to a stock SU-1 so can't really comment on what the improvements are. Honestly, the main reason why I got the fully modded SU-1 is mostly due to a bundled deal I got with the Kitsune DAC and the excellent service I get from Kitsune. I also don't plan on upgrading to another DDC for a very long time while I may consider other DACs that will still use the SU-1.

I briefly thought about adding the LPS-1 power supply, but based on the technical information in the last few threads, it will be redundant with what I already have.

 

[elan120]

My SU-1 has all the VR mods plus some other internal upgrades from Kitsune Hifi. Unfortunately, I never listened to a stock SU-1 so can't really comment on what the improvements are. Honestly, the main reason why I got the fully modded SU-1 is mostly due to a bundled deal I got with the Kitsune DAC and the excellent service I get from Kitsune. I also don't plan on upgrading to another DDC for a very long time while I may consider other DACs that will still use the SU-1.

I briefly thought about adding the LPS-1 power supply, but based on the technical information in the last few threads, it will be redundant with what I already have.

FWIW...I have the same DAC you have, and I think very highly of it. I recently completed an extensive modification to my SU-1 to accept 10MHz reference master clock that is feeding the USB input clock as well as the two output sampling clocks, and is very happy with how much jump in overall SQ from this mod. This result is with the same DAC, which I am very glad to find out how much potential SU-1 / Holo Spring L3 can do. Although, I believe making this extensive mod to SU-1 may not be for everyone, I do think to push more from SU-1 can be accomplished if you can get the remaining 4 stock VR replaced on your SU-1 main board, which isn't covered in KTE version according to their website, this will provide lower noise power going into the 3 oscillators as well as the XMOS chip.

Happy listening

 

[bflat]

...you can get the remaining 4 stock VR replaced on your SU-1 main board, which isn't covered in KTE version according to their website, this will provide lower noise power going into the 3 oscillators as well as the XMOS chip...

Kitsune added dual discrete regulators (both 5 and 3.3V) to the SU-1 in 2017. Are there more VRs than those?

 

[BlueDL]

FWIW...I have the same DAC you have, and I think very highly of it. I recently completed an extensive modification to my SU-1 to accept 10MHz reference master clock that is feeding the USB input clock as well as the two output sampling clocks, and is very happy with how much jump in overall SQ from this mod. This result is with the same DAC, which I am very glad to find out how much potential SU-1 / Holo Spring L3 can do. Although, I believe making this extensive mod to SU-1 may not be for everyone, I do think to push more from SU-1 can be accomplished if you can get the remaining 4 stock VR replaced on your SU-1 main board, which isn't covered in KTE version according to their website, this will provide lower noise power going into the 3 oscillators as well as the XMOS chip.

Happy listening

Also, are the VRs all surface mount and can they be fitted without taking the board out?
You’ve suddenly got me thinking about going the extra mile on my SU-1 !

 

[elan120]

Kitsune added dual discrete regulators (both 5 and 3.3V) to the SU-1 in 2017. Are there more VRs than those?

Yes, there are. The 5V regulator on their mod is for the stock power supply, and the 3.3V regulator is on the main board, supplying power to most of the chips on the output side except the two stock Crystek ocillators.

There are a total of 5 voltage regulators on the main board, the remaining four not replaced, two are on input side, their output is 3.3V and 1.0V taking the 5V input from USB input and supply power to all of the chips including XMOS and the 24MHz oscillator. Please note, the 1.0V regulator is a switch mode regulator, which by replacing it with a linear regulator, will help remove a source for generating high frequency noise.

The remaining two are 3.3V regulators on the output side taking 5V input from stock power supply and supply power to both Crystek CCHD-575 22.5792MHz and 24.576MHz oscillators.