Kt150

[Harlequin]

Good morning Folks .

FYI.

Having noted , elsewhere , an interesting and potentially pertinent comment from a DIY'er regarding some early findings within the compass of his own , non , ARC equipment I thought that I would mirror my thoughts there .

" Good morning Craig , as It looks like you have another month racked up on your KT-150's , I for one would appreciate any further consideration in this regard.

I was most interested to read your earlier comment ~

" Electrically they seem to work fine. I really question the raised heater voltage specification since it does not cause a bit of voltage drop on my heater circuit. The KT-120 didn't either... "

For my part I am running an ARC Ref 150 / KT-120 amplifier and It is my understanding that ARC are currently evaluating the KT-150 ( no doubt with an eye toward future models) as an user option in current model production in place of the KT-120.

Whilst we await the official Word from ARC , early rumour would seem to indicate that the Ref 75 /4 x KT-120 might receive sanction however this may not prove to be the case for the Ref 150 sporting 8 x KT-120's !

One might speculate that the Mains transformer / Capacitor tank of the Ref 75 may have a little more head room available , whereas the Ref 150 may not .

Which brings me back to your earlier findings with regard to actual live circuit readings , which I am hoping might indicate that there may prove to be sufficient head room left in the Ref 150 for ARC central to green light this option , especially when one considers that the output tubes in the ARC Ref 150 circuit appear to be run somewhat conservatively.

Jasper."

[Marck1973]

Interesting post so thank you. Will be intriguing what arc responds with in terms of using the KT150 in the Ref150

Marc.

[Harlequin]

Good morning Marc and fellow ARC'ers

Following a little gentle prodding the same chap who also performs repairs of ARC equipment would appear to have contacted the Mother Ship and advises us accordingly ~

" ARC is in the process of testing this tube. They are in the process of life testing the tube as well as sonic evaluations. They have not come to any decisions as of today. When I hear something more I will post "

We wait upon the Judgement of Caesar ~ or

[Number95]

Originally Posted by Harlequin

Good morning Marc and fellow ARC'ers

Following a little gentle prodding the same chap who also performs repairs of ARC equipment would appear to have contacted the Mother Ship and advises us accordingly ~

" ARC is in the process of testing this tube. They are in the process of life testing the tube as well as sonic evaluations. They have not come to any decisions as of today. When I hear something more I will post "

We wait upon the Judgement of Caesar ~ or

I see new generation ARC amps having KT-150 soon. I see that it is superior to even KT-120.

[microstrip]

Originally Posted by Marck1973

Interesting post so thank you. Will be intriguing what arc responds with in terms of using the KT150 in the Ref150

Marc.

KT150 in REF150? It risks becoming confusing!

One important aspect is that currently the KT150 lists for almost the double of the KT120 price.

[mulveling]

The KT150 lists heater draw at 1.75-2.0 A in "normal" circumstances. The KT-120 lists 1.70-1.95 A. At least with regards to heater draw, they're effectively equivalent, and I don't see how any properly designed amplifier that is OK supplying KT-120's would NOT be OK running KT-150.

Seems like ARC is operating in "cover our ass" mode, which is understandable for a company with a lots of expensive in-warranty amps out there.

[Marck1973]

Originally Posted by microstrip

KT150 in REF150? It risks becoming confusing!

Or more aligned :-)
Marc.

[microstrip]

Originally Posted by mulveling

The KT150 lists heater draw at 1.75-2.0 A in "normal" circumstances. The KT-120 lists 1.70-1.95 A. At least with regards to heater draw, they're effectively equivalent, and I don't see how any properly designed amplifier that is OK supplying KT-120's would NOT be OK running KT-150.

Seems like ARC is operating in "cover our ass" mode, which is understandable for a company with a lots of expensive in-warranty amps out there.

When you analyze the behavior of a tube in an amplifier circuit you have to consider the operation conditions, but also the transient conditions created at power up and power down, or even at some faulty conditions. Endorsing a new tube needs a lot of work and longevity tests, I would not expect ARC to take a rushed decision on this KT150 matter.

[djcxxx]

Originally Posted by microstrip

When you analyze the behavior of a tube in an amplifier circuit you have to consider the operation conditions, but also the transient conditions created at power up and power down, or even at some faulty conditions. Endorsing a new tube needs a lot of work and longevity tests, I would not expect ARC to take a rushed decision on this KT150 matter.

+1 I think that's right. Also ARC tests and discards a lot of tubes as well as selling only matched pairs for the power amps, so their tubes are pricier than what the general market normall bears for a given tube. The performance to cost ratio of the KT 150 may not be favorable for ARC to adopt it over the KT 120 given their process.

[Harlequin]

Nothing definitive as yet from ARC, however I thought I would post the latest snip-it from Gary (ARC certified Tech) ~

" 01-03-14: Hifigeek1
Still life testing and it is unclear if ARC will even sell these tubes due to the cost of each tube. I was told the tube exhibits a superb midrange. When I hear something after CES, I will post it to the thread. "