[dunski]

Quote:

Originally Posted by dunski /img/forum/go_quote.gif It's a black base with red print on it. I'm not sure if it has flat or triangular plates. I'll take a pic later and show you when I get home later tonight. I have to say though, I am VERY pleased with 5998 + CBS combo. -Steve.

Below is the CBS tube I'm using. It's a CBS 6SN7GTB black-base:

Sky, thanks again for the 5998

:

-Steve.

 

[Skylab]

Right, so that is a triangular-plate CBS 6SN7GTB. Nice tube. I prefer the Tung-Sol, but will be interested in your thoughts.

 

[HeatFan12]

Beautiful pics Steve.....

 

[DoubleEs]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif Tung-Sol did rebrand the 5998 for some companies, but I have never seen one Raytheon branded. Can you link to a picture? The key issue is - is it REALLY a 5998, and not a 5998A, or something else...

I emailed the seller about this and he said he made a mistake with his reply, he said it's a NOS TS-5998 he is sending me

 

[Skylab]

Well, that makes sense

 

[sacd lover]

I bought SEABREEZEs DV 336SE and I just started playing around with the DV tonight. I had to go to a standard 6SN7GT at first because of hum. Neither the 6F8G nor the 7N7 with their adapters would work without a hum in the left channel with the 5998. The sound was very good but the hum was definitely annoying. I had a 1950s Sylvania tall bottle lying around and once I put this tube in the amp was dead quiet.

For the output tube, I started with two different TS 5998s and they accentuated the hum. Once I got the Sylvania 6SN7GT in the amp though tube 5998 #2 was quiet. However, I soon got a loud pop with this 5998, which sounded like the tube was arching, so out the 5998 came. I then settled on a Chatham / TS 6080 as the output tube and no further problems.

After listening for an hour or so I decided to try something else. I used and adapter and a 9 pin tube called the 6GU7 .... which is a 6CG7/ 6FQ7 sub .... which in turn (the 6CG7) is often termed a 6SN7 in a 9 pin bottle. The Sylvania 6GU7 worked great .... more speed, better transparency and clarity and absolutely no hum. I find this tube to be extremely reliable, inately well matched side to side and almost always noise free.

I was driving one of the old Yamaha Orthodynamic headphones .... the YH-1. The YH-1 is very low sensitivity and demands lots of power. But, the 150 ohm impedance of the YH-1 allows the amps 6080 to develope more than enough power. The bane of these old orthodynamics is the lack of bass damping. But, I am finding with amps that can develope high power (like this DV or the SP Extreme can into this Orthodynamics 150 ohm impedance) can control the bass quite well. I definitely like this amp better than the Woo 3 I owned. In fact, I like this amp better than the Woo 6 I owned with these Orthos or the Senn 600 .... so far.

 

[Skylab]

Interesting stuff. My 336SE also sometimes hums, also in the left channel, with some 6SN7's. There seems to be no rhyme or reason to it. For example, it hummed recently with one of a identical pair of 6F8G's, and not the other! I know other 336SE owners have had the same issue. I'm guessing the 336SE, like the 336i before it, probably needs to have the "Fitz Hum Mod" performed to alleviate this issue, although I thought I had read that the 336SE actually had this mod incorporated as a part of what made it the "SE".

With no-hum tubes, the 336SE is a very nice amp for the money, I agree.

 

[Ash]

Hi Guys,
This my first foray into the tube world... I just purchased a DV 336SE to power my 701s and while I await its arrival, can someone suggest a basic set of tubes that wont cost a fortune, I can order for a good start to my tuberolling adventure? I would appreciate a link if possible too... I am reading the 2 tube rolling threads to familiarize myself with the usual suspects.
Thanks!

 

[Skylab]

A basic set of tubes would be an RCA 6AS7G, generally less than $10, and a decent RCA, Sylvania, or Tung-Sol 6SN7GTB - should be less than $20. You can get these at Antique Electronic Supply

 

[ElephantTLK]

What do you think of Tung-Sol 6550 tube? Is this to be used as back tube? I am new with tube amps so i need some information. I can buy 6550 but its difficult to find 5998 over here. So will this combination work well?

Tung-Sol 6SN7GTB & Tung-Sol 6550 Electron Tube

 

[sacd lover]

Quote:

Originally Posted by ElephantTLK /img/forum/go_quote.gif What do you think of Tung-Sol 6550 tube? Is this to be used as back tube? I am new with tube amps so i need some information. I can buy 6550 but its difficult to find 5998 over here. So will this combination work well? Tung-Sol 6SN7GTB & Tung-Sol 6550 Electron Tube

The 6550 is a completely different tube and absolutely WILL NOT work. The 6550 is a power pentode while the 6AS7/5998 is a dual triode.

 

[ElephantTLK]

Thank you! So i will go and search for 6AS7/5998 tubes. But Tung-Sol 6SN7GTB is good choice for front tube?

 

[Tridacnid]

There is the 6520, which I'm using in my amp.

I really like my NOS Tung-Sol 6SN7GTB, so yes, that would probably be a good front tube, IMHO.

 

[Skylab]

Quote:

Originally Posted by ElephantTLK /img/forum/go_quote.gif Thank you! So i will go and search for 6AS7/5998 tubes. But Tung-Sol 6SN7GTB is good choice for front tube?

Two things:

1. There is a "reissue" Tung-Sol 6SN7GTB, which is a current production Russian tube. Stay away from these.

2. Vintage Tung-Sol 6SN7GTB's tend to be quite good, yes, although there are different variants.

 

[Spareribs]

Can the 6AS7 be replaced with a 6080 tube for the Darkvoice?