6550 Tube Types

[opacheco]

Hi,

I would like to know where I can find a serious disscution about the sound of the 6550 tubes types(Tung Sol, GE, Tesla, Phillips, EH....)???

I would like to get a Complete Idea about what is the better for my application?...

Thanks a lot,
opacheco.

[Rob Mercure]

What's your application?

[opacheco]

What's your application?

Bass Amp, SVT II Ampeg, SVT 1972 Ampeg, 300 PS Fender.


Thanks
opacheco.

[MWJB]

Try the test reports at watfordvalves.com.

[telemoxy]

Hi,

I would like to know where I can find a serious disscution about the sound of the 6550 tubes types(Tung Sol, GE, Tesla, Phillips, EH....)???

I would like to get a Complete Idea about what is the better for my application?...

Thanks a lot,
opacheco.

Here is where I start. Check out the links they highlight in the text.

http://thetubestore.com/6550types.html

I found this very interesting.

http://www.triodeel.com/7027.htm

Is your SVT running 7027As?

[opacheco]

Here is where I start. Check out the links they highlight in the text.

http://thetubestore.com/6550types.html

I found this very interesting.

http://www.triodeel.com/7027.htm

Is your SVT running 7027As?

No, the SVT II and SVT 1972 use the GE 6550.

opacheco.

[telemoxy]

Try the test reports at watfordvalves.com.

Thanks MWJB. That's a good sight for reports.

[Rob Mercure]

In general the "winged C" brand - the original Svetlana until EH/Mike Mathews hijacked the trade mark (still won't buy or recommend those tubes for that reason) - perform well and their 6550 seems to be well liked. And the JJs also seem to be of good quality. The only current production 6550s I'd avoid are Chinese and the only Russian ones that I've seem a burned out example of are Sovwreks.

Rob

[telemoxy]

I"EH/Mike Mathews hijacked the trade mark"

Rob

That is strange a arrangement. New Sensor buys the Svetlana brand but Svetlana continues to sell the tubes under the Winged C SED brand. SED stands for Svetlana Electronic Devices so any one who does any research nows Winged Cs are Svetlana. So SED gets the money from the sale of the brand, continues to sell the same tube based on their excellent reputation and New Sensor invest money buying the brand and recovers it by making money selling Svetlana tubes on the Svetlana reputation that are not Svetlana.

Shades of Monty Python. It is like being caught in a catch 22 loop or the wild west or both. Makes life interesting though. Anyway, I love my Winged C SED 6L6GCs.

[soundmasterg]

That is strange a arrangement. New Sensor buys the Svetlana brand but Svetlana continues to sell the tubes under the Winged C SED brand. SED stands for Svetlana Electronic Devices so any one who does any research nows Winged Cs are Svetlana. So SED gets the money from the sale of the brand, continues to sell the same tube based on their excellent reputation and New Sensor invest money buying the brand and recovers it by making money selling Svetlana tubes on the Svetlana reputation that are not Svetlana.

Basically what it boils down to is this. The Svetlana factory in St. Petersburg, Russia is Russia's oldest factory for making tubes and one of the best in the world. They made tubes and sold them under the Svetlana name worldwide from when the iron curtain opened up until the late 90's/early 2000's. Their distributor for the US/Canada was Svetlana Electron Devices. SED went bankrupt and Mike Matthews/New Sensor saw a business opportunity and snapped up the rights for the US/Canada to use the Svetlana name and made their own tubes with the Svetlana name. The Svetlana factory had to sell their tubes as Winged C in the US/Canada or face a lawsuit.

Is your SVT running 7027As?

That article talking about 7027A's in Ampegs does not refer to the SVT, but to other Ampeg amps like the VT22, B18N, etc. The 7027A would never withstand the voltages in an SVT for very long without failure. The SVT historically has used the 6146B (early versions), and the GE 6550A (early 70's up until mid 80's), and other 6550 types since.

I have used GE 6550A's in my SVT before and I believe that is the best tube for these amps, but the cost is so exorbitant and supplies so scarce that modern types are a wiser course. There are many 6550/KT88 types these days that sound and perform well. I use Winged C 6550C's in my SVT and they sound great and hold up well. The sextet that is in my amp has been in there for 10 years and are still going strong. I use JJ KT88's in my Sunn amps and they are fabulous and sound great. I haven't tried them in my SVT yet. I also have some experience with the new Genelex KT88's in some Sunns, and they sound quite nice in that application. I've used OS Tung-Sol 6550's in Sunns too and they sound very nice but expense is a concern these days. If you go with Winged C 6550C or KT88, JJ KT88, EH KT88, Genelex KT88 or Tung-Sol reissue 6550, they should all give you excellent tone and service. If you want to spring for NOS, the GE 6550A are the creme of the crop for the SVT, and if you can find and afford them, the original Genelex KT88 is top notch too.

Greg

[telemoxy]

Basically what it boils down to is this. The The Svetlana factory had to sell their tubes as Winged C in the US/Canada or face a lawsuit.

Greg

Thanks for the clarification soundmasterg.

Regarding the V series amp referred to in that article (V4, VT22, V2, VT40) interestingly enough, the 6550 was a factory option on these amps. With four 6550s the V4 / VT22 produces 200 maximum and 112 clean watts according to The Tube Amp Book.

[Steve Conner]

My head hurts every time I try to remember this. So "Svetlana" tubes are now made by Sovtek, and the good ones from the original Svetlana plant are now Winged-C?

Anyone tried the coke bottle Tung-Sol reissue 6550s in a SVT, Fender 300PS or 400PS? They look great, but I thought they had a lower plate dissipation rating than the straight bottles. Also, the Fender amps run the tubes into grid current, and I'm wondering how well the reissue tubes stand up to that.

[kg]

incidentally, i recently sent an email to VTL regarding kt90s, which can be seen here:

http://ken-gilbert.com/correspondence-with-vtl-re-kt90s

[Rob Mercure]

SM,

Maybe, maybe not, here's where we disagree. I think that a "business opportunity" would have been to buy the name and either just "suspend" it or to sell it to the Svetlana folks at an exhorbitant price. Instead I see branding sovwerk and elcheapoharmonix tubes with the name as being FRAUD! Think about it - if Toyota forgot to reregister it's brand name (right!) and Diahatsu started slapping the little "cowboy hats" on their cars would that be only a "business opportunity."

There ain't much I can bitch about and feel that I'm making a difference but at least I can try and persuade the customers I've got to avoid these folks until they straighten up there ways (and there are many more other examples of shady dealings they've had over the years).

Don Quixote.

[Rob Mercure]

SM,

Maybe, maybe not, here's where we disagree. I think that a "business opportunity" would have been to buy the name and either just "suspend" it or to sell it to the Svetlana folks at an exhorbitant price. Instead I see branding sovwerk and elcheapoharmonix tubes with the name as being FRAUD! Think about it - if Toyota forgot to reregister it's brand name (right!) and Diahatsu started slapping the little "cowboy hats" on their cars would that be only a "business opportunity."

There ain't much I can bitch about and feel that I'm making a difference but at least I can try and persuade the customers I've got to avoid these folks until they straighten up there ways (and there are many more other examples of shady dealings they've had over the years).

Don Quixote.