AudioCircle

Audio/Video Gear and Systems => Tube-o-phile Circle => Topic started by: jbryngelson on 11 May 2021, 04:37 pm

Title: Which 6550 equivalent to try FIRST?
Post by: jbryngelson on 11 May 2021, 04:37 pm
I have a pair of DIY/Custom Mono Block tube amps that will have new 6550 tubes (Groove Tubes baby) coming in a week or so. I have been told the amps are tested and able to handle KT-88/120/150. They also will have a switch to allow for either Pentode or Triode mode with a tube based screen regulator. What tube would you spend $ to get the most out of them??  Where would you find your recommendation? TIA - Jeff in Detroit
Title: Re: Which 6550 equivalent to try FIRST?
Post by: FullRangeMan on 11 May 2021, 05:46 pm
I have a pair of DIY/Custom Mono Block tube amps that will have new 6550 tubes (Groove Tubes baby) coming in a week or so. I have been told the amps are tested and able to handle KT-88/120/150. They also will have a switch to allow for either Pentode or Triode mode with a tube based screen regulator. What tube would you spend $ to get the most out of them??  Where would you find your recommendation? TIA - Jeff in Detroit
Congratulations seems a nice amp, a Triode/Pentode switch is great since Pentode are better sound than UL. Favorite shops are Upscale and VTS, Andy at VTS have large experience and answer customers by the phone.

You will find that the best ones have a price, KT88 GENALEX Made in England are famous great sound also KT88 Svetlana C-Logo, however beware of the fakes on these famous tubes and rebranding, buy on a reliable shop.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: jbryngelson on 12 May 2021, 11:34 am
Thanks, I will give Andy a call.  I have heard great things about upscale audio. Sounds like Andy offers a fairly liberal return policy.  Might make for some really cost effective tube rolling! 
Title: Re: Which 6550 equivalent to try FIRST?
Post by: twitch54 on 12 May 2021, 02:10 pm
For years Jim has been my 'go to' guy for tube recommendations.........

http://www.mcshanedesign.net
Title: Re: Which 6550 equivalent to try FIRST?
Post by: opnly bafld on 12 May 2021, 02:56 pm
For years Jim has been my 'go to' guy for tube recommendations.........

http://www.mcshanedesign.net

+1
Title: Re: Which 6550 equivalent to try FIRST?
Post by: jjss49 on 12 May 2021, 05:58 pm
i believe the russian made genelax gold lion kt88's are the best among the direct 6550c subs on the market today (leaving aside more powerful versions like kt120 kt150 etc etc)
Title: Re: Which 6550 equivalent to try FIRST?
Post by: mick wolfe on 12 May 2021, 07:57 pm
For years Jim has been my 'go to' guy for tube recommendations.........

http://www.mcshanedesign.net

Yep, I'll only buy Genalex Gold Lion KT 88's from Jim. And yes, that tube is my favorite of the 6550 family mentioned by the OP.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: Tubefly on 14 May 2021, 01:20 am
For years Jim has been my 'go to' guy for tube recommendations.........

http://www.mcshanedesign.net

Ditto
Title: Re: Which 6550 equivalent to try FIRST?
Post by: rpf on 14 May 2021, 03:41 am
Congratulations seems a nice amp, a Triode/Pentode switch is great since Pentode are better sound than UL. Favorite shops are Upscale and VTS, Andy at VTS have large experience and answer customers by the phone.

You will find that the best ones have a price, KT88 GENALEX Made in England are famous great sound also KT88 Svetlana C-Logo, however beware of the fakes on these famous tubes and rebranding, buy on a reliable shop.

The original Genalex KT88 (England) are pretty much unavailable NOS now. If you could find a set - which is very unlikely - they would be astronomically expensive. What's more many say (including the well respected Jim McShane mentioned above) that the Genalex KT88 re-issue are their equal or superior. I've never heard the original but the re-issues are indeed very good. I did however prefer the Shuguang KT88 SC (previously sold as the Penta KT88 SC and now sold by TheTubeStore under their Preferred Label). The latter is a bit more refined than the Genalex. However I'd like to re-try the Genalex, cryo'd this time from Upscale Audio. That might close the gap between the two brands and Upscale has a stricter selection process than the other company.

The Svetlana "Winged C" line hasn't been made in several years (a shame as they - particularly the 6550 type - were superb) and the quality stocks of those tubes are long gone. The factory released some lower quality tubes at the end of their run and those are the only ones still floating around. Not recommended.

I haven't cared for the Tung-Sol re-issue power tubes. I've tried their 6L6GC and 6550 (tubes I normally love), and KT120. The first and third variety in a Rogue Cronus Magnum and the second in a pair of Quicksilver Mono 100s. All of these tubes had an overemphasized, even thick, bass. In fairness I don't recall hearing this in a pair of Rogue Apollo mono-blocks running KT120s I listened to one afternoon.

Aside from the above, it might be worthwhile trying the Sovtek 6550s from Upscale. They have been intriguing me for a while now as I always preferred the 6550 to the KT88. I'll buy them cryo'd if I do order them.

If your amp can take them and you don't need the extra power, the Genalex KT66 re-issue is excellent. Even better is the Reflector 6P3SE (6L6GC equivalent) which is getting a little hard to find now.

Good luck.



Title: Re: Which 6550 equivalent to try FIRST?
Post by: jjss49 on 14 May 2021, 03:50 am
mick wolfe can speak for himself but i don't think he meant original uk made and branded genalex gold lions...  he meant current russian made ones sold under the purchased trademarks
Title: Re: Which 6550 equivalent to try FIRST?
Post by: rpf on 14 May 2021, 01:22 pm
mick wolfe can speak for himself but i don't think he meant original uk made and branded genalex gold lions...  he meant current russian made ones sold under the purchased trademarks

I quoted Full Range Man - who was referring to the originals - not Mick Wolfe.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: jbryngelson on 14 May 2021, 02:56 pm
Great Info.  I will sort through this and try at least one set of Genalex KT88s RPF mentioned, and a set of Sovtek 6550s.  I need to talk to Andy as he is in my area, so I will put some trust in him first.  Thanks.  My amps are designed to handle power upto the KT150s, so I am confident I can go up and down the KT line.  The Triode/Pentode switch will be interesting.  My 6ohm 87db sensitive speakers may have a strong preference for one over the other - we shall see.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: mick wolfe on 14 May 2021, 04:15 pm
mick wolfe can speak for himself but i don't think he meant original uk made and branded genalex gold lions...  he meant current russian made ones sold under the purchased trademarks

Thx. Yes, I certainly meant the new re-issues. I'd never pay what's asked for "supposedly" NOS power tubes.



Title: Re: Which 6550 equivalent to try FIRST?
Post by: Tyson on 14 May 2021, 09:13 pm
I've always felt the new Russian tubes were a bit dry in the mids.  I recommend the Psvane Ti series for KT88's.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: jjss49 on 14 May 2021, 11:22 pm
using old stock pentodes like 6550's are truly for those with more money than sense in this day and age  :lol:
Title: Re: Which 6550 equivalent to try FIRST?
Post by: FullRangeMan on 14 May 2021, 11:39 pm
I think similar, most tube audiophiles persist year after year using commercial grade tubes at high prices to 2000 hours time life while there are top quality Russian military tubes at $20usd each.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: ASMAN on 10 Jun 2021, 02:52 pm
+2 for Jim McShane.
I only buy power tubes from him. Haven't gone wrong yet. Stick with a reputable dealer.
I like the GL re-issues for KT88. I will try the Shuguang some day. I have heard good things about them.
As a close second is Tungsol KT 120. Last place for me is Tungsol 6550.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: thorman on 10 Jun 2021, 06:38 pm
I will second on the Russian Reflector 63PSE . Incredible tube and hard to find but worth it if/when you do..It is all about System Balance and in the Leben CS600 I found this Reflector tube out did all others mentioned. Your mileage may vary, but if you can find a nice Quad of the Reflectors, they are worth every penny.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: FullRangeMan on 11 Jun 2021, 03:14 am
I will second on the Russian Reflector 63PSE . Incredible tube and hard to find but worth it if/when you do..It is all about System Balance and in the Leben CS600 I found this Reflector tube out did all others mentioned. Your mileage may vary, but if you can find a nice Quad of the Reflectors, they are worth every penny.
Seems Russian Reflector 63PSE is a typo, you may referring to the 6P3S or 6P3S-E or 6n3c-E which are plenty available at GSTubes from Reflector or Foton at low prices, which are definitely good news.
http://www.gstube.com/catalog/?key=6p3s&submit=Find
Title: Re: Which 6550 equivalent to try FIRST?
Post by: Tom Bombadil on 11 Jun 2021, 03:40 am
Seems Russian Reflector 63PSE is a typo, you may referring to the 6P3S or 6P3S-E or 6n3c-E which are plenty available at GSTubes from Reflector or Foton at low prices, which are definitely good news.
http://www.gstube.com/catalog/?key=6p3s&submit=Find

It should be noted that the 6P3S-E is not a 6550 equivalent.  It is a 5881 / 6L6GB equivalent with a 19 watt plate limit. 

In my amps I find the new Gold Lion KT88 to be superior to the 6P3S-E. 
Title: Re: Which 6550 equivalent to try FIRST?
Post by: rpf on 11 Jun 2021, 03:42 pm
Also the 6P3S is not exactly the same as - and not as good as - the 6P3S-E.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: Tyson on 11 Jun 2021, 03:46 pm
Hmmm, I have a set of 6 Russian 6P3S-E tubes I bought about a decade ago.  They've just been sitting in my tube box collecting dust, maybe I should give them a shot.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: jbryngelson on 22 Mar 2022, 03:42 pm
UPDATE on the Journey:  I received my amp with Groove-Tube 6550 tubes and put it in my system.  It sounded great, but like many I was itching to Tube Roll.  I sent Email to Andy, but never received a reply.  I read about and watched the Upscale Audio site but never called to order anything.  My Amp Tech recommended some UOS (Used Old Stock) Sylvanias stamped as AMPEX on Ebay, so I bought them for $325 for (4).  Put them in and Amp sounded great.  Sadly it Red Plated on one tube, and had to go back to the Tech.  Now I am told the Tubes are VERY Used, and likely will return to the Groove Tubes.  I Called Andy at VTS, and had a delightful conversation.  I am considering a NOS set of Tung-Sols or GE Pre-Microwave Division (Per Andy) for about $800.  I also have ordered a set of British Military 6550 equivalents the 12E14 tubes for a song (Less than $200), as NOS.  I plant to have my tech review and install/bias them to optimal settings here soon.  I am hoping the 12E14s will really shine and might keep me from spending the big $$ for NOS GE/Tung-Sol. 

jeff in Detroit
Title: Re: Which 6550 equivalent to try FIRST?
Post by: opnly bafld on 22 Mar 2022, 04:24 pm
According to one tube data sheet I found the 12E14 should have pin 6 (beam plate) tied to pin 8 (cathode), these are connected internally on a 6550/KT88.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: FullRangeMan on 22 Mar 2022, 07:40 pm
Sadly it Red Plated on one tube, and had to go back to the Tech.  Now I am told the Tubes are VERY Used, and likely will return to the Groove Tubes
Ebay is full of used tubes on the end of life, usually they are advertised as strong and can die at any moment.
It is not a good idea buy used tubes.
Title: Re: Which 6550 equivalent to try FIRST?
Post by: Freo-1 on 22 Mar 2022, 09:20 pm
The GE6550A is my favorite 6550. 
Title: Re: Which 6550 equivalent to try FIRST?
Post by: opnly bafld on 23 Mar 2022, 01:56 am
The GE6550A is my favorite 6550.

Sure why not, if you can find a matched set and can afford them if you do.