[Rossliew]

  My Carbon CC [built this year] has an Alps RK50 pot in it. 

Correct me if I'm wrong but the CC was a special cost no object take on the Carbon..shouldnt it be the Penny & Giles pot?

 

[Pale Rider]

 
Correct me if I'm wrong but the CC was a special cost no object take on the Carbon..shouldnt it be the Penny & Giles pot?

I don't know if I would call the CC a "cost no object" take on the Carbon. I think Birgir has something else in the works for that title. But the CC does have an improved power supply and a "few other improvements." In any case, the CC I bought [I think he only built a very small number, maybe as few as two earlier this year], has—per Birgir, unless he changed his mind after bench-testing the amp (ha!)—an RK50. I haven't opened it up to be sure, and I probably won't. Amp is sublime. I have not done a lot of side-by-side testing with my other Carbons and KGHVSS, but the CC is the one I use with my Select II.

 

[Rossliew]

  I don't know if I would call the CC a "cost no object" take on the Carbon. I think Birgir has something else in the works for that title. But the CC does have an improved power supply and a "few other improvements." In any case, the CC I bought [I think he only built a very small number, maybe as few as two earlier this year], has—per Birgir, unless he changed his mind after bench-testing the amp (ha!)—an RK50. I haven't opened it up to be sure, and I probably won't. Amp is sublime. I have not done a lot of side-by-side testing with my other Carbons and KGHVSS, but the CC is the one I use with my Select II.

Yes, he did mention something altogether more abominable than the CC But i recall he built two units and one of it had a Penny & Giles pot. Perhaps the second one was with an RK50, nonetheless, it's still top notch stuff. Hope to hear your impressions against your other Carbon. Birgir builds some very good stuff. Listening with his SuSy Dynalo PureBipolar dynamic amp now - yes, sublime is THE word!

 

[astrostar59]

  I don't know if I would call the CC a "cost no object" take on the Carbon. I think Birgir has something else in the works for that title. But the CC does have an improved power supply and a "few other improvements." In any case, the CC I bought [I think he only built a very small number, maybe as few as two earlier this year], has—per Birgir, unless he changed his mind after bench-testing the amp (ha!)—an RK50. I haven't opened it up to be sure, and I probably won't. Amp is sublime. I have not done a lot of side-by-side testing with my other Carbons and KGHVSS, but the CC is the one I use with my Select II.

Does it have the GR PS with shunt boards? I thought it didn't. Saw a pic of the insides a while back.

 

[kevin gilmore]

RK50 vs P&G.   Roughly the same price, and roughly the same performance. I have a few of each.
 
A RK27 is a much cheaper mass market pot.

 

[sarora]

I talked to Kevin and Birgir a few hours ago and they once again told me what I had thought. I am not going to quote what they told me in public completely as it wasn't related to the whole KGDT vs. KGST thing . But "As for the KGDT, it is the same circuit as the KGST just run at lower current and voltage to suit the dual triode tubes." was mentioned." which is again, from today.

It doesn't take much longer to build a KGST. The board designs are open hardware for personal use as most of Kevin and Birgir's things are. Once you have the parts and especially the PCB unpopulated, it may be like 2-3 hours more of raw soldering for the KGST but the price they charge is $800 more. But they don't hang out here much anymore for a reason.

And yeah they'll build anything to an extent -- if you want to replace the potentiometer with something like a stepped attenuator (such as the Elma or DACT switches) then that's not a terribly hard mod, but it'll cost of course.

I think the potentiometer is chosen either to keep some type of unity between models or what is at hand, or it could be that is what works best when testing that amp. I'm not sure. I do know that there's not a massive difference in the standard Alps or Alpha for the most part and I know that Kevin/Birgir are both technical engineers. They go by engineering not by design though the design is fine..it's what's on the inside there that does actually count. So looking inside one of their amplifiers should give you an idea of its construction quality and right away there are things you can point out that are done way better than, for example, Stax. Birgir even told me a while back that he had to push Justin who made the BHSE to implement the passive XLR outputs. Not sure about everyone here, but that is a huge benefit that I think many other companies neglect. It is a tiny PCB for two XLR slots and a few wiring point to point and you're completely passive -- that makes insierting any of their recent (as far as I can think) stuff really easy into your potentially complex chain of audio.

 

[Pale Rider]

In the case of my CC, what Birgir told me is that he got a "screaming deal" on the RK50 that made the price of the CC more reasonable. The size of the RK50 did require a slightly off-center alignment of the volume control, but it's only noticeable when you notice it. Worked for me. And I think you are right @sarora that they are engineers first.

 

[Pale Rider]

Does it have the GR PS with shunt boards? I thought it didn't. Saw a pic of the insides a while back.

Don't know.

 

[wuwhere]

Alps RK50 is not cheap. Is that what KGSSHV DIYers use?

 

[Tinkerer]

size of the RK50

 
You should see the one I'm sticking in my new amp that got pulled from an old radar station. 3"x3.5", biggest pot I've ever held in my hand. Might be garbage, but I couldn't help grabbing it for cheap since it had the right resistance for audio and all four gangs track within .5% of each other.

 

[Pale Rider]

You should see the one I'm sticking in my new amp that got pulled from an old radar station. 3"x3.5", biggest pot I've ever held in my hand. Might be garbage, but I couldn't help grabbing it for cheap since it had the right resistance for audio and all four gangs track within .5% of each other.

Post a pic!

 

[Tinkerer]

Sure thing. Try to ignore the horribly unsafe floating stuff except for scale. I was testing some things this morning.
 

 

[kevin gilmore]

most of those are instrumentation pots and don't have stops at 0 or 360 degrees.
you might end up with a surprise when you turn it past zero

 

[Tinkerer]

  most of those are instrumentation pots and don't have stops at 0 or 360 degrees.
you might end up with a surprise when you turn it past zero

That's why the volume is getting marked very carefully. Might also put a peg stop on the knob. And though it still measures good from what I can tell, it might turn out to be junk. It is probably thirty years old after all. I just figure it's worth trying because when is the next time I'll have an enclosure big enough to try it?

 

[goobicii]

over a year,since it was revelead,I dream about the Nanotube/ciclotron/4x 500v floating power supply DIY Gilmore push pull beast of a amp
 
there is one four page thread already about it but its kinda dead and I just cant handle my appetite for some information.From what I reed,Kevin mentioned some new even better ultra low noise power supplies,and I think some kind of "digital" bias thing he is working on that could be put into it...
 
did anybody hear it? build it?        how much would be the cost of the parts in Europe?   I remember there is problem fitting all that stuff into single chassis where it needs to be becose of the dangers asociated with such power,I was thinking I would just make my own extra large custom chassis so that would be non issue
 
Kevin mentioned its little lower distortion,the push pull effect should cancel second order harmonic by atleast 6db if I remember correctly,is it even audibly different that Birgirs Carbon?