kt 150

[ToneMerc]

I have done some KT150 tests during the last year published here http://www.diyaudio.com/forums/tubes-va ... kt120.html

Very interesting reading through all the threads and links, thank you.

I run the KT120 tubes for MI amp but I want to get a PT that has separate plate and screen supply so I keep the screen voltage safely lower. More experimenting needed on my part but I'm not technically inclined like you.

Mark

Mark, I have all the parts to build an ODS clean only preamp mated with an Odyssey PI driving a KT120 pair . My power setup should be around 585-590V on the plates and screens are half of that, with dual bias pots and a bias circuit that should adjust them between 50-80% at idle.

This should have been done by now, but I got sidetracked by Songwriter build.

TM

[cbass]

Hmm I was just thinkin my 100 watt amp isn't really all that loud

[Jana]

WHAT?

[ToneMerc]

the 50k max grid leak for fixed bias is a red flag to me

I think that the 6550 has the same limiting value on that?

I remember someone putting forward the idea that the grid resistance limiting value is most pertinent at max plate dissipation.
Such that as the plate dissipation is reduced, the grid resistance can be increased.

The KT88 info sheet seems to comply with that rationale http://www.mif.pg.gda.pl/homepages/fran ... k/KT88.pdf

I want to get a PT that has separate plate and screen supply so I keep the screen voltage safely lower

I think that the 'typical operating conditions' of the tube info sheets were often based on separate supplies from the same PT winding, achieved by having a cap input filter after the plate supply rectifier, and a choke input filter after the screen supply rectifier (which might only be half wave rectified). Thereby giving good regulation on the screen supply, where it's most beneficial.

Correct, no different than a 6550A, which is 50K. On my KT120's I'm limiting total grid resistance to around 82K (75 + 5.6 grid stoppers) and don't anticipate any issues.

TM

[M Fowler]

Mark, I have all the parts to build an ODS clean only preamp mated with an Odyssey PI driving a KT120 pair . My power setup should be around 585-590V on the plates and screens are half of that, with dual bias pots and a bias circuit that should adjust them between 50-80% at idle.

This should have been done by now, but I got sidetracked by Songwriter build.

TM

I'll look forward to your ODS hybrid build then.

[Stevem]

I would sooner build up a power stage in A/B2 and run 6550s or 88s!
May be use one of the 150s as the driver in AB2, sorry just kiddin!

[rp]

New Sensor so I assume Russian? Does NS even do Chinese even as a reseller?

Good or bad, useful or useless, it's good to see these tube companies innovating in 2014. Energy might be better spent on QC and making tubes as good as they were in the 1950s, but maybe one step at a time.

[Richie]

bang for buck looks like the KT 120 might be a good choice.

also many overlook these that were made or converted to an octal base.>
http://www.thetubestore.com/Tubes/Big-P ... JJ-EL509-S


which I think the tube store lists all of the tubes mentioned.

[Leo_Gnardo]

New Sensor so I assume Russian? Does NS even do Chinese even as a reseller?

New Sensor would be interested only in promoting and selling their Russian tubes, which AFAIK are now made only in the Saratov facility. (Of course if anyone has more detailed info, please do fill us in!)

It's not likely they would promote tubes from their competition. However anything might happen. If Mike Matthews detects a way he might make a buck, count on it, he will.

Their labels and brands include Sovtek, ElectroHarmonix, Mullard, TungSol, Svetlana*, GEC Genelex Gold Lion. Maybe more, chime in if you know of any, folks.

* NS's "Svetlana", AFAIK may be distributed anywhere but North America because of the foofaraw surrounding their acquisition of the right to distribute tubes with that name on them ALTHOUGH they were not actually manufactured by Svetlana in St. Petersburg Russia. True Svets distributed in North America from about 2000 on with the flying c =C= label. The real Svetlana =C= haven't made any "consumer" tubes for several years now and have no plans to revive the line, much to the chagrin of many fans who considered them a premium marque.

[cbass]

I refuse to buy tubes from anyone that uses old brand names or uses the word reissue. I've got some real tung sols no need for fakes

[Leo_Gnardo]

I refuse to buy tubes from anyone that uses old brand names or uses the word reissue. I've got some real tung sols no need for fakes

What's more aggravating is when they issue "reissues" of tubes that were never made by those brands. What a farce.

OTOH the hi fi nuts claim some of those New Sensor GEC Genelex "Gold Lion" KT88 KT77 KT66 are actually quite good. Being generally cheapskates (including me), the guitar/bass amp crowd seems to avoid them.

Further, New Sensor offers no price breaks that I know of to the direct buyer, so you're always better off buying them from a distributor, even more so if distributor tests & matches them. A local store made a deal to stock up at a discount, almost every tube New Sensor sent them was fit for the rubbish bin. Of course New Sensor wasn't much in a mood to yak on the phone about dud tubes, much less replace them or refund. Lesson: don't bother us with your small time deals. $500 - 1,000 orders don't impress us. Call only if you're going to spend $10,000-20,000 or more, otherwise it's not worth our time. We're a big important company, don't you know?

[Richie]

New Sensor does sell sino china tubes. Don't see any Shugang tubes.
They also list JJ and many others.

Also those tubes I posted a link to, seems tubes and more sell those one single tube price alot cheaper than what a single tube [dealer cost] could buy from NS. Looks like those are close to the dealer 10 tube price cut, or about a buck more.

[cbass]

I refuse to buy tubes from anyone that uses old brand names or uses the word reissue. I've got some real tung sols no need for fakes

What's more aggravating is when they issue "reissues" of tubes that were never made by those brands. What a farce.

OTOH the hi fi nuts claim some of those New Sensor GEC Genelex "Gold Lion" KT88 KT77 KT66 are actually quite good. Being generally cheapskates (including me), the guitar/bass amp crowd seems to avoid them.

Further, New Sensor offers no price breaks that I know of to the direct buyer, so you're always better off buying them from a distributor, even more so if distributor tests & matches them. A local store made a deal to stock up at a discount, almost every tube New Sensor sent them was fit for the rubbish bin. Of course New Sensor wasn't much in a mood to yak on the phone about dud tubes, much less replace them or refund. Lesson: don't bother us with your small time deals. $500 - 1,000 orders don't impress us. Call only if you're going to spend $10,000-20,000 or more, otherwise it's not worth our time. We're a big important company, don't you know?

Man I ain't got no idea bout spendin no 20,000 bucks on tubz but I hear ya man . I wasn't aware about the tung sols el34s must be super rare.

[Leo_Gnardo]

those tubes I posted a link to, seems tubes and more sell those one single tube price alot cheaper than what a single tube [dealer cost] could buy from NS. Looks like those are close to the dealer 10 tube price cut, or about a buck more.

see what I mean... not a friendly place to do biz, unless you got bags o' cash.

New Sensor does sell sino china tubes. Don't see any Shugang tubes.
They also list JJ and many others.

That's what I get for not checking NS site out before I typed. Woops. I'll have to see how the prices on Sino & JJ compare between NS and tubesandmore for a lark.

[Phil_S]

Anyone done business here? KT-150 at the very bottom. Pricey. Sheeks!
http://www.boiaudioworks.com/kt88#TungSol_KT150-TS