ARC Ref 110 with KT 150 tubes

Jasper and David, ... other than double secret hearsay comments that have been published here and on another website, I have *NOT* read or heard directly out of ARC's metaphorical mouth that the KT-150s are approved for use in other models, be they current amps or older models. If either of you gents can point me and the others to a direct *OFFICIAL* source, the collective "we" would be grateful.

(@Jasper, you are the official A'gon grammarian, should I say "the us'es" as in "us" plural instead of saying the "collective we"?? I want to come off as an erudite.)

David, ... having said all of that, until and unless ARC blesses the KT-150s for use in the ARC Ref 110, I would be very cautious about dropping in the KT-150s. As an "fyi" the current Ref series amps (i.e., Refs 75, 150, 250 and 750) were designed to run with KT-120s. The KT-120 is a more robust tube and draws considerably more current than its predecessor, the SED 6550 "winged C."

Stated differently, the marginal difference in power draw between the 6550 and the KT-120 is much greater than then the marginal increase in power draw between the KT-120 and the KT-150. Check the web yourself to confirm what I am saying.

Nevertheless, it would not surprise me that ARC, if and when it gets off its royal corporate arse, may ultimately bless the KT-150s for use in the Ref 110. ARC amps are very robust and can take a "lickin' and keep on tickin'" so to say.

In the meantime ... we wait for its royal majesty to get off the can. And as the official A'gon audiophillic (sp?) erudite Wolfman would say, it's time to can it sweet prince. Say goodnight Gracey. LOL :)

@Jasper ... not sure I concur with the practical take of your last response. It would be a pure greed play by ARC to withhold the KT-150s approval if they otherwise would not damage the current ref line of amps. Sh*t, who is to say that even if ARC approves the KT-150 that I would buy from ARC .... for $200 a tube. I think not.

Next, my amp was purchased pre-owned from a dealer. Upshot is still no factory warranty. I am dubious that a dealer would go crosswise with ARC.

Having said that, one dealer did in fact post on anther A'gon thread double secret hearsay information sourced back to ARC that the KT-150 was approved for use in current ARC amps. When I spoke to ARC a week or so later, the tech folks denied the bona fides of the report because it came from a marketing guy ... not the tech department.

Go figure.

I'm a big boy. I'll make a decision shortly. If I opt for KT-150s, I'll take my chances.

It's spelled whining .. not wining. If you're going to chide me, at least spell it correctly! LOL

I used to own the ARC VS-115 amp which came stock with Svetlana SED 6550 winged Cs. ARC later approved the KT-120 for use in the VS-115. IMO, the KT-150 ... hands down ... was a big improvement over the SED 6550 winged C. Better dynamics. Better bass control. More headroom. Just plain sounded better.

Having said that, I couldn't stop "wining" when the Svetlana factory burned down and reliable SED 6550 winged Cs became scarce. As my fellow ARC preamp and source component owners may know, the SED 6550 winged C was used in the power supply of many ARC source components and preamps. ARC now uses the 6550WE, which I believe is made by Sovtek.

IMO, I think the difference between tube types is of much greater import in ARC's amp gain circuits as compared to the preamp or source component power supplies. IOW, I think the 6550WE, or the 6550 Tung Sol re-issue (also made in Russia) works just fine in the power supply applications.

Perhaps Al or Ralph could better explain why (if at all) that might matter.

Signing off for a glass of whine.

Well said Wolfy. I'm tired of wining (or is it whining) about those stupid KT-150 tubes. Oh ... and who ever said I would buy KT-150s from ARC for $200 each. Talk about meshuganah. Upscale charges $100 per tube and even that is too much.

@Jamnesta -- just for fun and giggles, I dropped a (Russian new issue) Tung Sol 6550 into my ARC Ref 5 SE. It sounded just fine. As I said, ARC uses the 6550 in the power supply (PS) of its preamps and source components. I surmise that the branding is less important in the PS application as compared to the gain circuits of the amps. Just a guess.