Elekit 8200 Tube rolling

It would be great if you could chime in on this guy's thread:
http://www.diyaudio.com/forums/tubes-valves/288680-appj-pa0901a-anyone.html
He is planning on building his first hifi tube amp kit. The amp you own is one i recommended. He has been trolling the chinese fodder on ebay and I hate to see people make mistakes. Sharing your experience with the piece might help him in this direction.
 

fredjones

Member
2013-05-02 9:08 pm
I honestly like the stock tubes that came with my 8200 the EH 6L6GC. I have also rolled in some other power tubes such as Gold Lion KT88s that sounded pretty good too, more power. Shuguang Treasure KT88 TII sound the most detailed, so if you have no preamp they are the better ones.

The 12AU7 rolling can make a big difference too. The stock chinese tubes had to go of course. Jan Phillips 5814A I liked a lot. I tried some NOS tungsol that sounded smoother but I don't run them regularly.

I have heard that Elekit is coming out with a new amp this summer and I eagerly await its arrival. It's nice to hear from another Elekit owner, sometimes I feel like they are not that popular. I definitely love putting together the kit though.



http://www.thetubestore.com/Tubes/12AU7-ECC82-Tube-Types/JAN-Philips-ECG-5814A-12AU7
 
Hey fredjones, I get the same feeling that the Elekit is not that popular on this forum. If so, people are missing out a great little amp and so much fun to tube roll and experiment in different output modes. I'm running some EH 6ca7 tubes in mine tonite, they really sound great, you should give them a try. To me they have the great punch of the EL34 with the sweet clarity of the 6L6, what ever that means...LOL!
 

Dimu

Member
2016-05-29 2:48 am
Rolling tubes in this amp is almost too much fun :)

So far I tried the following power tubes: GEC KT66, 6P3S from USSR, RCA 6L6GC, GE 6L6GC, Sylvania 6L6GC, GE 7581, Sylvaniya 6550, GE 6550, different XF versions of Mullard EL34, RTF EL34. So far GEC KT66 is my favorite, especially the Gold Monarch version which for some reason sounds better than regular GEC KT66. I am going to try couple different tubes with top anodes to see how those compare, including TT21. Basically the only notable tube I have not gotten my hands on is Tung Sol 6550. I was planning to try 350B but Elekit told me that second grid voltage spec on those is too low to be used safely in TU-8200. Could not try 6P3S-E for the same reason.

I also tried many driver tubes including Telefunkens, RCA, Sylvania, Brimar, Mullard, GE, etc. My two favorites are Brimar 12BH7 and Amperex E80CC (both require upgraded rectifier and cannot be mixed with anything other than 6L6GC power tubes). I am planning to try 6SN7 next.

Also did some 12AT7 tube rolling in my TU-8500 preamp.

My stock Chinese/Russian tubes were used only on initial power up to see if they blow up. As soon as amp/preamp were confirmed to be operational those tubes were ejected for good. I don't see any reason to use new issue tubes when there are so many good choices original tubes. If budget is an issue I would recommend combination of Brimar CV4003 and GE or Sylvania 6L6GC for TU-8200. This tube complement can be had for just over $200 which is not much relative to the cost of the amp kit.

The reason I love TU-8200 (in addition to the awesome sound) is that it is easy and affordable to roll tubes compared to amps that require matched quads of power tubes and many driver tubes. Output volume is more than enough for me with my KEF LS50, especially having preamp available for bringing weaker signals up.

I also had a lot of fun upgrading components in the 8200 and 8500 kits includings pots, capacitors, resistors and opamps.
 
Power tubes in Elekit 8200

I know this an old thread but I've been rolling the power tubes in my Elekit 8200 for a long time. This little amp kit is a work horse don't think I could be happier. The best for me is the 6550. Love the deep bass pop and clarity of this tube. I'm running it thru some DIY Fostex Fe206en double bass reflex speakers...mancave is rocking...
 
One more, well really two more things:
1. Tungsol reissue 12AT7 are decent, almost as good as NOS Mullard and not nearly so flaky and fraught with problems.
2. Try replacing the coupling caps (C3, 4, 9 & 10) with mid grade Mundorfs. Even the standard Supreme (about at about $11 each) should provide a sonic lift. Just put 50 to 100 hours on them before judging.

Steve
 
One more, well really two more things:
1. Tungsol reissue 12AT7 are decent, almost as good as NOS Mullard and not nearly so flaky and fraught with problems.
2. Try replacing the coupling caps (C3, 4, 9 & 10) with mid grade Mundorfs. Even the standard Supreme (about at about $11 each) should provide a sonic lift. Just put 50 to 100 hours on them before judging.

Steve

Yes, Steve I'm already using the Tungsol 12AT7 (great recommendation), as for coupling caps, I went with Wima MKP-10, fit really nice, I've been so tempted to go with the Mundorf upgrade but I have liked the sound from this amp so well I've stalled, since you recommend I guess I'm gonna have to do it..I'll let you know how it turns out...Thanks man, Cheers...
 
6550 tube

The 6550 tube in this amp is by far my favorite so far. Wow, I have done many many comparisons, the 6550 is huge, full big punchy bass, crisp detailed highs, seems to be much tighter than the KT88's. I know this is subjective but isn't that what HIFI is all about...I'm having fun with this great amp...
 
Genalex Upgrade

I just updated my tubes to Genalex. One of my stock 6L6 tubes was having problems and tripping the protection circuit so I took advantage of some black friday shopping deals and finally upgraded. I went with KT-88s and upgraded the 12au7s and 12at7s as well ( I also have the TU-8500 pre-amp). I must say, I feel like I ran the stock tubes too long. I still plan to eventually open up the amp and try the different modes, but immediately I was hearing detail I hadn't heard before and the bass definitely filled in more. I am running some Fostex FE206EN full range back-loaded horns that I built from a Madisound kit. I put on a copy of Wish You Were Here that I had just picked up as a first listen and was blown away by my meager system all over again.
 
I have the TU-8500 as well. Makes for a really nice little system. I found that the kits were a real pleasure to build, great instructions, and parts packaged nicely. Both of mine fired up with no issues. I'm really tempted to build those BLH's from Madisound and compare to my double bass reflex cabinets (I'm not much of a wood worker). I've run strictly in the pentode mode, and haven't had a reason to change since it sounds great to me, and I'm too lazy to take it apart to change the jumper. Try the 6550 tube and compare to the Kt-88, I think I'm liking the 6550 better??
 
Modify the cover to change modes easily

Caveman :)

Read the 6moons review (link on the vkmusic.ca site on the TU-8200 page), it's a couple of pages into the review. The author describes the mod making two holes in the top cover to facilitate changing output modes.

Making large holes (> 1/4") in sheet metal can be tricky. If you are not comfortable doing this yourself mark the position you want the holes and seek out a local too and die shop. Show them what you want and tell them you'll pay cash. If you pick a standard size (say, 1/2", 5/8", 3/4") the shop can make a clean hole with a standard end mill. They'll even make you a couple of nice covers for the holes out of brass, stainless steel, or whatever you like if you ask nicely.

Cheers, Steve
 

sharpi31

Member
2005-10-20 12:57 pm
VKung has recommended the 5965a a few times, so it seems the TU-8500 is fine with the higher filament current. This gave me the confidence to try some Mullard E180CC which seem great so far (E180CC has higher filament current that 12AT7/12AU7, but less than 5965a).

Another decent (cheap) option to play with :)
 

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Another worthwhile upgrade is to replace the output caps. (Between the two tubes in your picture.) The stock caps are OK but nothing special. The basic Mundorf Supreme caps aren't very expensive in the value needed. A bit of lead bending would be necessary and maybe sliding a bit of tubing or stripped-off insulation over the cap leads would be a good precaution against any electrical grief.

S.
 

sharpi31

Member
2005-10-20 12:57 pm
Agreed. I ran the numbers and the stock 0.47uF caps at the outputs will roll off a bit early for my liking (with a typical amplifier input impedance). I used 2.2uf ECWF at the main outputs and also at the outputs of the phono section. They look a bit like the standard ones but they’re not ;)

I think my days of oil / silver / fancy caps are behind me. I’ve got tons in boxes but am generally pretty happy with decent polypropylene and polystyrene caps (that have a data sheet and good specs).

I’d definitely address the cap values before worrying about boutique options.

Edit: I used alternative electrolytics in all places. The standard caps are very decent, but it’s not a huge cost to upgrade to superior parts with 8-10K hour lifespan at 125 degrees C. Electrolytics always kind of bug me, as they degrade over time (more than most other components) so I pretty much always start with top spec parts. I do check ripple current, ESR etc to ensure I’m meeting/improving on the parameters of the standard parts.
 
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