[hans888]

And I found as well the transformer manufacturer, Tamura...
It's the first one on the list, PESB 28-12... It doesn't say anything about input voltage

https://www.tamura-ss.co.jp/jp/products/electronic_components/download/trance/pdf/power_pesb.pdf

 

[hans888]

Well, in the end I desoldered the transformer and measured it with a variac. It's a single Primary/Secondary. With an input of 100v I got 10,6v. 11,6 with 110v and 12,6v for 120v. So I stopped checking, at 230V either it had burned or the output would be around 24v, way too much.
Since I didnt hear from Teac (I wrote them twice), I ordered another Tamura transformer, model 3FD-210, for 5€. You only need to set it for 230V and 10V output and bend a bit the pins so that they fit into the PCB.

I'm trying it today for the first time in my second system, coaxial inputs (digital output from cd player and 320/flac files from foobar) and I have to say that I'm really impressed. My old B&W DM320's never sounded this good from a digital source. And it's just the stock unit. Huge soundstage and the bass is amazing.

During this long waiting I already ordered some caps, Nichicons KA and KZ and Jantzen Silver. Will do it in the next weeks to see if it gets even any better. BTW, which is the best way to remove the white glue around the PS caps?

 

[37mil]

Well, in the end I desoldered the transformer and measured it with a variac. It's a single Primary/Secondary. With an input of 100v I got 10,6v. 11,6 with 110v and 12,6v for 120v. So I stopped checking, at 230V either it had burned or the output would be around 24v, way too much.
Since I didnt hear from Teac (I wrote them twice), I ordered another Tamura transformer, model 3FD-210, for 5€. You only need to set it for 230V and 10V output and bend a bit the pins so that they fit into the PCB.

I'm trying it today for the first time in my second system, coaxial inputs (digital output from cd player and 320/flac files from foobar) and I have to say that I'm really impressed. My old B&W DM320's never sounded this good from a digital source. And it's just the stock unit. Huge soundstage and the bass is amazing.

During this long waiting I already ordered some caps, Nichicons KA and KZ and Jantzen Silver. Will do it in the next weeks to see if it gets even any better. BTW, which is the best way to remove the white glue around the PS caps?

well done with the transformer! Good thing it was readily available. I emailed the service center (third party outsourced) here in the uk and they said it was unavailable.

nichicon are good. I used them for the power caps as well. Just put a screwdriver to the white glue. Comes off quite easily. Don’t scratch the pcb though! Or if you find it tough put a bit of heat gun on it a while.

the pcb sinks quite a bit of heat and some components will be troublesome to remove. Easy though if you have the right equipment.

 

[hans888]

Well, I wrote to Tamura too and they told me the original transformer it's an OEM part and almost impossible to get. But just a 230/10 which fits will do the trick.
Thanks for the instructions, I'll try to take care.
The idea is replacing the PS KMG's with Nichicon KA's, although I think those Chemicons KMG are not bad caps at all. The KZ's will replace the 100uF Suncons (the green/gold ones which seem to be among the best from Suncon -high ripple/low esr-, but probably not as good as the KZ's)
For the output caps, my amp has 220K input impedance, so theoretically I'd be done with somethinkg like 0,36uF. However, I've read here that some people had bad results with low capacitance output film caps. If the engineers decided 100uF there must be a reason... So I've thought about 100uF KZ's bypassed with 1uF Jantzen Silver Z-Caps. Don't know if it's a good idea but it's the best I had so far

 

[37mil]

Replacing the output caps on the voltage regulators has a big impact on the sound. I originally replaced with elna simlic but sounded too thick and dark (heavy bass and muted treble) so I got rid of all caps on regulator outs by using discrete regs from new class d. Not cheap though.

 

[hans888]

Yes, another 100€ at least. By now I got 10 Kz's but if I'm not happy I'll follow your advice.

 

[hans888]

Yesterday and today I've been testing the UD-501 (still stock unit) against a Musical Fidelity A5.5 Cd with all the stock electrolytics just replaced with Nichicon (audio) caps and with the stock tubes replaced as well with (nowadays quite expensive) NOS vintage tubes. You can believe me, it's a great sounding cd player.
I connected the CD coaxial digital output to the DAC with a coaxial cable so that the source was the same, a cd. Both coaxial cables from CD and DAC to the amplifier same model and brand. I didn't check the outputs with a multimeter but dind't need to play with the volume, to my ears same level from both. So I could just switch with the remote from cd to dac and viceversa at any second.
I played some cd's that I know very well and are all great recordings. Different genres. For instance:
Smog - A River...
Pink Floyd - DSOTM (20th anniversary ed.)
Lambchop - Ohio
Screaming Trees - Sweet Oblivion
Electric Wizard - Witchcult Today

I will keep it short cause I don't have the technical vocabulary and don't want to make a fool of myself. Only in the bass area I like the cd better than the dac. Bass guitar low notes and drum bass for instance, go lower and you can hear and feel physically its impact much clearly from the cd player. Other than that, the differences are really subtle. In some songs the cd sounds a bit more detailed or with a slightly wider soundstage, but in many i was switching A/B and couldn't hear any difference at all.

To sum up, I think at the prices one can get hold of this DAC second hand (i paid 300€ for mine), it's an absolute bargain. Very fine piece of equipment.
I'd love to replace the power supply caps with big Nichicons KG's but there's no room, so the idea is trying Nichicon KA's instead. My primary target is to get that little bit more of bass.

 

[37mil]

Yesterday and today I've been testing the UD-501 (still stock unit) against a Musical Fidelity A5.5 Cd with all the stock electrolytics just replaced with Nichicon (audio) caps and with the stock tubes replaced as well with (nowadays quite expensive) NOS vintage tubes. You can believe me, it's a great sounding cd player.
I connected the CD coaxial digital output to the DAC with a coaxial cable so that the source was the same, a cd. Both coaxial cables from CD and DAC to the amplifier same model and brand. I didn't check the outputs with a multimeter but dind't need to play with the volume, to my ears same level from both. So I could just switch with the remote from cd to dac and viceversa at any second.
I played some cd's that I know very well and are all great recordings. Different genres. For instance:
Smog - A River...
Pink Floyd - DSOTM (20th anniversary ed.)
Lambchop - Ohio
Screaming Trees - Sweet Oblivion
Electric Wizard - Witchcult Today

I will keep it short cause I don't have the technical vocabulary and don't want to make a fool of myself. Only in the bass area I like the cd better than the dac. Bass guitar low notes and drum bass for instance, go lower and you can hear and feel physically its impact much clearly from the cd player. Other than that, the differences are really subtle. In some songs the cd sounds a bit more detailed or with a slightly wider soundstage, but in many i was switching A/B and couldn't hear any difference at all.

To sum up, I think at the prices one can get hold of this DAC second hand (i paid 300€ for mine), it's an absolute bargain. Very fine piece of equipment.
I'd love to replace the power supply caps with big Nichicons KG's but there's no room, so the idea is trying Nichicon KA's instead. My primary target is to get that little bit more of bass.

I use Nichicon KW for power supply but the config I have now runs quite hot, not sure if it’s all the discrete op amps I’ve put in which I think are mainly class A biased, so KA might be the better option with the higher temperature rating.

once you start changing caps there will be profound impact on the bass. The quality of caps on the voltage regulators will have a big effect.

get a pair of sparkos op amps. Highly recommended for wide, open soundstage and equally balanced quality treble and bass. I think they slightly beat the burson v6 vivid with clearer treble and leaner bass. The v6 bass was too heavy for my system and I finally gave up after 6 months use.

I found that the voltage regulator caps heavily affected the sound and got rid of them altogether.

 

[hans888]

Had big success replacing the output caps of my phono stage with jantzen alumen, so I decided to place 4 of them (1uF) in parallel with 4 Nichicons KZ (100uF) at the DAC output stage. Apart from that I replaced the other 100uF caps with KZ's, the 4700uF with Nichicons KA and the 1800uF with Chemicon KMG.
I'll check the outcome during the next days...

 

[hans888]

Well, it's been weeks instead of days. Just after the recap I noticed a clear improvement in separation and hights. The low frequency area was way better than before but still not as good as the cd. I was temped to disassemble it again, take out the Nichicons KA and find the way to solder 4 spare Nichicons KG 4700uF I have in there. I dind't and gave it some time. Yesterday and this morning I made a last comparison cd/dac and I hardly can't tell any differences in the low frequency area. I'm really happy how this dac sounds.