SUN Audio SV-2A3 SET Valve Amp - new build

[Lightstream]

1 hour ago, stereonut said:

Your enthusiasm is contagious! You may have covered this in your post, but love to know where you purchased the TU 8500 and what power amp you’re using?

I think I’ve seen the kits on Parts Connexion. 

SN

I ended up buying the kit from an eBay seller, using the voucher offer as well, which took another $40AU+ off the price, the upgrade op-amps were from an eBay site too (don't recall which one) and the Amtrans resistor kit and Mundorf caps from the Parts Connexion. I also didn't use the stock op-amp sockets supplied with the kit, using some HQ gold plated ones I had on hand. 

 My lounge has two systems, the TV/movie system uses a restored Pioneer home theatre amp which surprises me with it's clarity and tuneful behaviour, matched with a pair of Gale Mini Monitors and a Jamo sub. Second play system is a vintage Technics outfit I was given, as it was in rough exterior condition, needing the lids of both the receiver (SA 290) and tape deck (an RS-B105 in remarkable sonic condition, if not the exterior) almost completely stripping back and repainting, they've come up very well. A couple of caps needed replacing in the amplifier section, but otherwise all is well. The t/t was a belt drive Technics SL-BD20 that was so corroded from salt air that it took some time to separate the platter from the spindle! Other than that, a general clean up, bearing clean and lube, new belt and a new stylus from LP Gear (elliptical instead of the spherical original) and it runs perfectly, the arm being in excellent condition for it's age, good bearings with not a trace of slop. It's since become my spare t/t as I now have the Technics SL 1900 in it's place. With a pair of JBL MX 1500 speakers that I re-foamed both drivers on, it's a fun vintage system to use while I rebuild a valve-based more enthusiast system, starting with the TU 8500. I do have a separate power amp that I built using two tiny mono boards I bought from an outfit in Adelaide that seems to have moved elsewhere now. It's a good 50W a side using pairs of the ubiquitous Toshiba 2N3055/2N2955 transistors and only 22 parts all up per channel. It's a remarkably clean and tunefully musical little creation, but currently there is no space for it too, so I use the TU 8500 into a highly modified Silicon Chip HP amp with a Class A audio-gd power supply to run it, in itself having more than enough grunt to run a preamp as well. The amp uses all Dale resistors, Nichicon Muse and Black Gate caps and either two OPA627BP op-amps on a Black Dog adapter for the input stages, or an audio-gd Earth HDAM.

 With the TU 8500 as a preamp and either the Questyle QP1R via optical out into the Schiit Audio Mimby DAC, or the SL 1900 t/t and Stanton 681EEE as sources. Either way, it's the finest I've ever heard this HP amp sound in some 9 or 10 years. Headphones are almost always my 30 year old Sennheiser HD540 Reference, with pleather pads and Mogami cable (as I have done for all my headphones). IC for the system are the fabulous pure silver Slinkylinks from NZ and silver La Cacanya cables from White Zombie. I am about to make up some Mogami ICs for the Pre to amp link. 

 The Elekit preamp was bought from these guys, who gave excellent service: japanmegamall (4177)

 I know, my enthusiasm has driven me to write more than expected, eh?  

PS Parts Connexion no longer carry this particular kit. 

 

Edited January 18, 2019 by Lightstream

[stereonut]

12 hours ago, Lightstream said:

I ended up buying the kit from an eBay seller, using the voucher offer as well, which took another $40AU+ off the price, the upgrade op-amps were from an eBay site too (don't recall which one) and the Amtrans resistor kit and Mundorf caps from the Parts Connexion. I also didn't use the stock op-amp sockets supplied with the kit, using some HQ gold plated ones I had on hand. 

 My lounge has two systems, the TV/movie system uses a restored Pioneer home theatre amp which surprises me with it's clarity and tuneful behaviour, matched with a pair of Gale Mini Monitors and a Jamo sub. Second play system is a vintage Technics outfit I was given, as it was in rough exterior condition, needing the lids of both the receiver (SA 290) and tape deck (an RS-B105 in remarkable sonic condition, if not the exterior) almost completely stripping back and repainting, they've come up very well. A couple of caps needed replacing in the amplifier section, but otherwise all is well. The t/t was a belt drive Technics SL-BD20 that was so corroded from salt air that it took some time to separate the platter from the spindle! Other than that, a general clean up, bearing clean and lube, new belt and a new stylus from LP Gear (elliptical instead of the spherical original) and it runs perfectly, the arm being in excellent condition for it's age, good bearings with not a trace of slop. It's since become my spare t/t as I now have the Technics SL 1900 in it's place. With a pair of JBL MX 1500 speakers that I re-foamed both drivers on, it's a fun vintage system to use while I rebuild a valve-based more enthusiast system, starting with the TU 8500. I do have a separate power amp that I built using two tiny mono boards I bought from an outfit in Adelaide that seems to have moved elsewhere now. It's a good 50W a side using pairs of the ubiquitous Toshiba 2N3055/2N2955 transistors and only 22 parts all up per channel. It's a remarkably clean and tunefully musical little creation, but currently there is no space for it too, so I use the TU 8500 into a highly modified Silicon Chip HP amp with a Class A audio-gd power supply to run it, in itself having more than enough grunt to run a preamp as well. The amp uses all Dale resistors, Nichicon Muse and Black Gate caps and either two OPA627BP op-amps on a Black Dog adapter for the input stages, or an audio-gd Earth HDAM.

 With the TU 8500 as a preamp and either the Questyle QP1R via optical out into the Schiit Audio Mimby DAC, or the SL 1900 t/t and Stanton 681EEE as sources. Either way, it's the finest I've ever heard this HP amp sound in some 9 or 10 years. Headphones are almost always my 30 year old Sennheiser HD540 Reference, with pleather pads and Mogami cable (as I have done for all my headphones). IC for the system are the fabulous pure silver Slinkylinks from NZ and silver La Cacanya cables from White Zombie. I am about to make up some Mogami ICs for the Pre to amp link. 

 The Elekit preamp was bought from these guys, who gave excellent service: japanmegamall (4177)

 I know, my enthusiasm has driven me to write more than expected, eh?  

PS Parts Connexion no longer carry this particular kit. 

 

This is really 'hands-on' audio. Makes me feel a lazy listener!

Edited January 19, 2019 by stereonut

[Lightstream]

32 minutes ago, stereonut said:

This is really 'hands-on' audio. Makes me feel a lazy listener!

Haha  I've been 'hands-on' since I was 17 years old - some 45 years ago - with a few years off and I still consider myself a beginner ... It's fun, creative and, like my parallel photographic passion, comes with a child-like fascination for audio and cameras (the latter since I was 4-6 years old). I'm no technical whizz, not really having the left-brained training and understanding for it, but enough skill to understand the basics and plenty enough to put a kit together or create a headphone amplifier from some parts and a board and assemble the musicians, so to speak  

 I co-created the FrankenZero (cheap Tianyen Zero) DAC/HP amp with a friend from Canada who is no longer with us (he started the process), highly modified, if not quite to LampenZero standards. Replaced all the stock caps and op-amps with better versions and bypassed them with the wonderful Russian ex-military PIO caps, something I also did with my kit power amp (and other designs), it makes a difference! I thought about using these PIO caps in the TU 8500, but didn't have the correct values, so went with the Mundorfs instead. All good fun. 

[stereonut]

Guru update 19/1/19. 

Now onto the signal side with Kaisei caps going in and wiring up the outputs.

[stereonut]

Guru update 20/1/19.

Rainy day offcuts of Deulend wire coming in handy.

[Lightstream]

3 hours ago, stereonut said:

Guru update 20/1/19.

Rainy day offcuts of Deulend wire coming in handy.

Lovely  Is that Deulend wire "good stuff"? I have heard of it briefly years ago but know nothing of it. I like to keep notes for future projects! 

[stereonut]

2 hours ago, Lightstream said:

Lovely  Is that Deulend wire "good stuff"? I have heard of it briefly years ago but know nothing of it. I like to keep notes for future projects! 

I've only used for Speaker Cables and Interconnects and found it excellent value. Plenty written by Jeff Day on his blog - https://positive-feedback.com/author/jeff-day/

[stereonut]

Guru update 20/1/19 (3.40pm WST)

Almost 70% there. The resistors and caps have Teflon tubing insulation. Also new AN Speaker terminals and RCA's.   

[Gryffles]

Looks very neat and meticulously put together

[stereonut]

Guru update: 22/1

Adaptor to hold in place the copper foil caps.

[stereonut]

Guru Update 23/1/19

About 85% there and looking good Huston.

[Lightstream]

2 hours ago, stereonut said:

Guru Update 23/1/19

About 85% there and looking good Huston.

A work of art! Beautiful. What price are the copper foil AN caps? Or is it scary to ask  And, why the choice of the copper foil caps over others, please? 

[maxsimonjp]

Hi, that s sound crazy to me but what a job and upgrade on the Sun Audio. I probably did a shitty job building mine and keeping all the original components. I am very curious how yours will sound.

Did it come with the Sovtek 2A3 ? And are keeping them ! I do but i changed the original 6SN7 for the Sophia Electrics and it improved a lot

Well it was my first move to the world of SE class A amp and i enjoy it every day since.

I hope you will too.

[stereonut]

18 hours ago, Lightstream said:

A work of art! Beautiful. What price are the copper foil AN caps? Or is it scary to ask  And, why the choice of the copper foil caps over others, please? 

It goes something like this: Copper foil sounds much better than tin or aluminium. They use solid silver legs and a solid copper tube. Teflon dielectric, only bettered by the silver foil which are $680 each for the 0.22uf value.

Price is around $93 and they retail in UK for 50 quid. So a good price here in Oz.

 

 

[stereonut]

14 hours ago, maxsimonjp said:

Hi, that s sound crazy to me but what a job and upgrade on the Sun Audio. I probably did a shitty job building mine and keeping all the original components. I am very curious how yours will sound.

Did it come with the Sovtek 2A3 ? And are keeping them ! I do but i changed the original 6SN7 for the Sophia Electrics and it improved a lot

Well it was my first move to the world of SE class A amp and i enjoy it every day since.

I hope you will too.
 

Good to hear from another SV owner. The intro to my post will give you a sense of why I'm doing this. Like you, I love the sound and decided to take the plunge to see what's possible. I had had some correspondence with a group in Europe who were that positive about upgrading and compared their amps with Shindo and Kondo. I'm not saying I'll necessarily get there, but all indications are positive. I know that Bryan (Guru) has very happy Audio Note customers after upgrades to Audio Note amps.

In my current (15 year old) SV-2A3 I run the Sovtek 2A3 with RCA 6SN7's and a U52 rectifier. As a  basic kit with these tubes it's been my favourite amp and if this upgrade opportunity hadn't arisen, I probably wouldn't have hit the upgrade button. The new amp comes with Psvane 2A3, so that will be an interesting comparison to run in my old one  

Stay tuned    

[Lightstream]

55 minutes ago, stereonut said:

It goes something like this: Copper foil sounds much better than tin or aluminium. They use solid silver legs and a solid copper tube. Teflon dielectric, only bettered by the silver foil which are $680 each for the 0.22uf value.

Price is around $93 and they retail in UK for 50 quid. So a good price here in Oz.

 

 

Thank you. That's not quite as scary as I thought it would be ..... silver foil on the other hand ..... !

$93 is much better than I thought it would be, almost reasonable, isn't it, especially for the said benefits. 

 By any chance have you tried any of the Russian ex military KY series of PIO caps? I've used them as bypass caps in a number of projects to great effect, admittedly they are much cheaper! 

[mwhouston]

On 09/01/2019 at 11:52 AM, stereonut said:

Here we go! 

First off - Copper Foil caps to replace the kit suppled Film Caps.

 

SN

I’ve used the Jensen copper foil in PIO in three builds and thought they sounded excellent. I did roll them against anything else just used them right from the start.

 

The ANs would have been expensive. I’ve used AN tin PIO in power amp and MC stage. Once more thought them very grounded and good.But once more not rolled against anything else. In the power amp - Tamarisk, EL84 amp - the amp really stood out as something special.  The caps would have played a big part in that.   

[stereonut]

2 hours ago, Lightstream said:

Thank you. That's not quite as scary as I thought it would be ..... silver foil on the other hand ..... !

$93 is much better than I thought it would be, almost reasonable, isn't it, especially for the said benefits. 

 By any chance have you tried any of the Russian ex military KY series of PIO caps? I've used them as bypass caps in a number of projects to great effect, admittedly they are much cheaper! 

This is my first venture into anything like this - no previous experience to measure against. I'm just enjoying the ride while Bryan does all the work 

[stereonut]

1 hour ago, mwhouston said:

I’ve used the Jensen copper foil in PIO in three builds and thought they sounded excellent. I did roll them against anything else just used them right from the start.

 

The ANs would have been expensive. I’ve used AN tin PIO in power amp and MC stage. Once more thought them very grounded and good.But once more not rolled against anything else. In the power amp - Tamarisk, EL84 amp - the amp really stood out as something special.  The caps would have played a big part in that.   

I'm looking forward comparing to my old SV-2A3 which has all original parts .

SN

[stereonut]

Guru update 24/1/19:

Almost there. AN Silver litz in place. 98% done.

[Lightstream]

11 minutes ago, stereonut said:

Guru update 24/1/19:

Almost there. AN Silver litz in place. 98% done.

As a regular builder over the years, I can't help but notice the coiled red and grey wiring, why might this be so? Is the extra  .. mm, probably inductance, part of the circuit, or is it just convenient in some way? 

[Gryffles]

4 minutes ago, Lightstream said:

As a regular builder over the years, I can't help but notice the coiled red and grey wiring, why might this be so? Is the extra  .. mm, probably inductance, part of the circuit, or is it just convenient in some way? 

I'm guessing unused taps for the transformer?

[stereonut]

25 minutes ago, Gryffles said:

I'm guessing unused taps for the transformer?

Spot on Ben

[TD19]

Needless to say I am following this thread with great interest Peter.

[stereonut]

1 hour ago, TD19 said:

Needless to say I am following this thread with great interest Peter.

Good to hear from you Tony. And thanks for getting me into the SV-2A3 groove!