[jamato8]

Fwiw on my own Mainline which I built in 2015 I had installed RTI 10uf tin foil teflons for the output capacitors. In 2020 I thought I would give the 0.01 Duelund silver foil bypass caps a go. I was expecting some small improvement but in all honesty the silver foil Duelund bypass caps made the largest step change in sonics I've ever experienced in installing a capacitor.

I have since transplanted them onto the Vcap cutf in my TU-8900

I would echo the requirement for 400-500 hrs of burn in with the Vcaps and the AM transformers.

Both the Cossor WE2A3 & WE300B tubes purchased new from Victor with the amp took about 100hrs before settling down and coming on song.

Some don't get the need for forming the caps etc., which has been an ongoing debate for years. But it has been shown that chemically and the electrical properties of even PCBs change, which is why glass boards are so nice. Also why Black Gates often got a poor rap, because they didn't sound spectacular and it was not believed by many, that they needed up to 800 hours to burn in and would deform some, when not used and the process had to be started again, taking 100 to 200 hours. Audio Note UK, even suggested always having a charge on them, so they maintained the forming and best performance, which I agree with.

The Duelund silver foil, when a cap in the signal path is needed, would seem to be a very fine choice, at a price of course.

 

[HiGHFLYiN9]

I was looking at possible cap upgrades in the power supply and saw the price of those Audio Note Kaisei; $228 for a single 100uf 500v electrolytic. I'm not sure a lot of those will sell at that price

 

[petewebb]

I was looking at possible cap upgrades in the power supply and saw the price of those Audio Note Kaisei; $228 for a single 100uf 500v electrolytic. I'm not sure a lot of those will sell at that price

The Kaisei caps won't fit the TU-8900. As it is the standard AN 100uFs just barely fit, I had to use longer leads on a few resistors to make room for the 100uFs. The 6800 uF's are really small too, I think they are 16mm wide in a very cramped area which is a shame as I had some really nice Nichicon KGs I wanted to use there.

but yeah those non-polar Kaisei are crazy expensive.

 

[HiGHFLYiN9]

I saw you had to creatively mount the snap-in 50uFs (looks very good), didn't realize the resistors had to be moved for the 100uFs. There is real estate back there if you really wanted to fit larger caps, you'd just need to mount them sideways to the board and run leads. There's a lot of dual section caps out there (50uF + 50uF, 100uF + 100uF) so plenty of options. Jensen and Mundorf are both solid choices. The Unicon might be a little too large... those are more for old school builds with the caps protruding from the chassis.

You can do the same thing with the 6800uFs. Just mount em with 3M tape.

If there is a will, there is a way. This is a nice secure mount

 

[petewebb]

I saw you had to creatively mount the snap-in 50uFs (looks very good), didn't realize the resistors had to be moved for the 100uFs. There is real estate back there if you really wanted to fit larger caps, you'd just need to mount them sideways to the board and run leads. There's a lot of dual section caps out there (50uF + 50uF, 100uF + 100uF) so plenty of options. Jensen and Mundorf are both solid choices. The Unicon might be a little too large... those are more for old school builds with the caps protruding from the chassis.

You can do the same thing with the 6800uFs. Just mount em with 3M tape.




If there is a will, there is a way. This is a nice secure mount

I attached some screenshots of the 100uFs. There is a resistor and a diode that is pretty close to them, I really didn't need to move them far, as you can see. In fact, they probably would have just fit if I hadn't moved them, but I didn't want anything touching each other.

On the 50uFs, yeah I did have to make some shims out of heat-resistant rubber. The thinner part of the snap-in lead was enough to make them pretty secure when soldered, but I wasn't sure how electrolytic caps deal with vibration so I thought I'd put the dampening shims in there just in case.

You are right though, I think the 6800's would fit if I just tilted the outer ones to the side a bit.

Oh, one thing I forgot to mention, for anyone inserting/removing the 2A3/300Bs for the first time... Those sockets are extremely tight before getting worked in(usually they all are, but this was excessive). I scraped the crap out of the pins on my brand new 2A3s the first time I removed them. Kinda glad it was those and not the WE300s though. I even had Deoxit contact cleaner/lubricant on-hand but was too excited to turn the amp on for the first time and forgot to use it. Don't make that mistake like I did

 

[HiGHFLYiN9]

Very good advice, thanks for that Pete. I'll probably get the 100uF Audio Notes but do something else for the 47uF... or just keep the stock whatever it is. Partsconnexion seems to be out of a lot of stuff so I'm going with HiFiCollective. I need my pink resistors to match!

Since you're done with project maybe you'd like to build the Millett Sangaku? It's a lot less expensive! You get to build a $2K amp for like $600-700.

...I'm finishing mine up now, just need the fuse. On the topic of creative capacitor mounting... lol. I have Jupiter 0.1uF and Clarity Cap 1.0uF wedged in there. Interestingly they are the identical size.

The DIY addiction never ends...

 

[petewebb]

Very good advice, thanks for that Pete. I'll probably get the 100uF Audio Notes but do something else for the 47uF... or just keep the stock whatever it is. Partsconnexion seems to be out of a lot of stuff so I'm going with HiFiCollective. I need my pink resistors to match!

Since you're done with project maybe you'd like to build the Millett Sangaku? It's a lot less expensive! You get to build a $2K amp for like $600-700.

...I'm finishing mine up now, just need the fuse. On the topic of creative capacitor mounting... lol. I have Jupiter 0.1uF and Clarity Cap 1.0uF wedged in there. Interestingly they are the identical size.



The DIY addiction never ends...

Oh wow, that looks neat!

I've got a feeling the Dynaco ST-70 restoration is going to keep me busy for a while though. I just spent all weekend buying up parts and planning the restoration. It's pretty clean as is, it came from the original owner, and even has the original tubes and an unpitted/no-rust chassis.

I also just got a Burson Soloist 3X GT late last year. I need to start using that more as well, also given I spent a bunch of money switching out all the OpAmps for Sparkos.

I'll add the Millett Sangaku to my list for future projects to look at though, Thanks!

 

[HiGHFLYiN9]

Got the kit today! The chassis should play basketball as it's super tall

I took a look at the electrolytics, and unusually for a kit these are the exact caps I would actually purchase from Mouser for the purpose. 105C and high ripple rating, so they are good enough for wherever my arbitrary line in the sand is. Props to Victor and/or Elekit for packing some good ones. I may bypass with Wima polypropylene on the bottom if I have some in the parts bin.

The resistors are magnetic (probably steel leads) as well as the 0R jumper resistors (odd that they packed these when people could just use bus wire... maybe it's faster/easier) so I'll probably replace the resistors with cheap and cheerful Takman or Amtrans AMRT and the jumpers with solid silver that can oxidize without detriment. The unit looks like it would accept Cardas posts but the plastic piece that connects them would need to be cut in half. Other than that, it appears no mod is needed. The RCAs are a big mystery and I don't think I'll be able to tell until later in the build.

Thanks guys for maintaining the fun thread and I'll post updates soon.

 

[EagleWings]

The RCA on it is not a regular one. It has an internal switch and my friend found it shorts to ground or something if no RCA cable is plugged in.

 

[HiGHFLYiN9]

The RCA on it is not a regular one. It has an internal switch and my friend found it shorts to ground or something if no RCA cable is plugged in.

I took a look at them and confirmed there is a mechanism. I've seen that plenty of times on a TRS but not on an RCA before. Will need to stick to stock for those in that case.

I ordered the resistors from HiFiCollective and should have 'em early next week. It was about $100 to get Takman/Mills replacements for all of them if anyone is budgeting a new build. I know Victor offered them previously but was not stocking at the moment. Also I checked the through-hole dimensions to accept about 22awg or 0.7mm.

 

[toobuzz]

I received a resistor upgrade package for the 8900 yesterday. I’m not quite sure when I’ll get around to installing them, but Victor does seem to have this available. It’s mostly AN Tantalum with a couple AMTRANS and a couple Takman REX50G, a total of 50 resistors.

I’m also waiting on a pair of Shuguang Treasure 300B-Z to arrive. I look forward to comparing them with the Genelex Gold Lion.

A friend of mine, @basstrombone80, built an 8600 (with Lundahl) so there will be opportunities for comparisons all around!

 

[HiGHFLYiN9]

The non-magnetic AN tantalums should be very nice in there. If you don't mind my asking what was the package cost? I just got the Takmans yesterday but haven't installed them. If the ANs are a good deal I might be tempted.

 

[toobuzz]

So, the ANs appear to be the basic tantalum’s, at least based on the images from Hifi Collective. I’d hate to put a price in this thread, especially with the current state of supply chain/inflation. I will say that they were in the $250 - $300 range, including overnight shipping. I wasn’t expecting it to be that much, but I like working with and supporting Victor.

 

[pgkrish]

Has anyone tried running the Susvaras out of the speaker taps of the 8600/8900?

 

[HiGHFLYiN9]

Takman resistors and jumpers installed. HiFiCollective had some silver-gold Mundorf wire that wasn't very expensive, so I used that for the jumpers. I noticed their purpose was to allow the board to be printed single-sided for cost reduction, which is perfectly fine. I know first-hand that running an audio business is not as lucrative as it may seem

Then an end of the day relaxation session.