The new KT120 from tungsol

[nhuwar]

Hi Guys,

I'm wondering if anyone could point me in the right direction. I'm looking at this new kt120. Comparing the data sheet from it and the old kt88.

The number seem the same to me. Max anode voltage and current for each are the same on the spec sheet. I attached the 2 spec sheets.

I might be missing something obvious but I cant see how it can have a higher dissipation if the max anode current and voltage are the same for it and the kt88.

Thanks for the help,

Nick

 

[hidnplayr]

Max plate dissipation is not related to max current nor voltage!
It depends on the construction of the anode, and its ability to dissipate heat..

Max voltage and current are limited by other factors. (emission, flash over voltage, ...)

 

[nhuwar]

But still haw can it produce more power then a kt88 though. I know dissipation has to do with the physical properties of the anode.

Nick

 

[hidnplayr]

Maybe its just bigger, or another material wich dissipates better or simply can withstand higher temperatures.

I'm no expert tough.

 

[nhuwar]

I guess I left out which Im trying to find out. If the specs are pretty much the same. How can a pair of kt120 produce 150 watts in ab1.

 

[Eli Duttman]

IMO, unless you are building a guitar amp, don't waste time on the KT120. A look at the data sheet shows how non-linear the type is. 🙁 Another consideration is increased heater current draw, compared to the KT88.

 

[Tubelab_com]

Forget the data sheet. The first spec I look at is the price. At $71 each I can think of a zillion ways to better spend my money. Look through the red board thread there are plenty of sweep tubes that can make 150 watts per pair for less than $10 each. They sound good too. I have seen a pair of hamfest 35LR6's crank out 250 WPC in the magic red board. I got them for under $4 each, and I bought a lifetime supply!

 

[nhuwar]

I will check it out George.


Nick

 

[nhuwar]

Is this the thread your refereeing too?

http://www.diyaudio.com/forums/tubes-valves/169867-10-pounds-power-15-a.html


Nick

 

[Tubelab_com]

No, look through this one. Pete posted a design on his web site and he sells the PC board on Ebay. I think his original design target was somthing ridiculously small like 20 WPC. I bought one because it was similar to a project that I started a few years ago and never finished. I built mine without the onboard power supplies so that I could feed it externally and crank things up. I think that my original statement was that I would be dissapointed if I couldn't get 50 WPC. That turned out to be the understatement of the year. 50 WPC flowed out of it the first time I flipped the switch. The record now stands at 250 WPC cleanly and continuously although the tubes were running over spec, and about 340 WPC into clipping. The two channels paralleled through a single OPT made 504 watts. At least two other builders have achieved 100 WPC with 6HJ5's which are $5 each at ESRC.

Tinkering with this board has rekindled the fire to build a big amp using a similar topology, but I have several experiments to do first and no time right now.


http://www.diyaudio.com/forums/tubes-valves/151206-posted-new-p-p-power-amp-design.html

 

[nhuwar]

Got it, Thank you sir.

nick

 

[nuvistordave]

Since I won $600 recently in a Poker tourney; I decided to splurge on a set. I have a DOS-based SOFIA curve tracer courtesy of a contracting stint with Svetlana back in the day. I also have a amp that I built up running Mesa Strategy 400 OPTs and a MQ of JJ KT88's. Drive tubes are NOS 6KV8's with the triode sections set up as a paraphase and the frame grid sections direct coupled to the KT88 control grids thru a 100-Ohm grid stopper. The Meas trannies have the SG taps hidden under the bells; they are hooked up to make this amp an Ultralinear rig.

So stay tuned; I will provide curves and output data from the amp

 

[nhuwar]

Sounds like one killer guitar rig.



I hope you have some good ear plugs, LOL.




Nick