Responses from hifigeek1

Need recommendations to replace ARC VT100 MkII
If you like the way your ARC sounds, I would just get an ARC integrated amp. That being said, you will not get the same bass impact that you currently get on the VT100mkII. The SP-3C is a superb preamp and I would think twice about replacing it. I... 
When I turn it up, it turns down
Try unplugging your Nad for a few minutes. Plug it back in and see if that solves the problem. 
capacitors to Thrshold S/160 amp
Try and find the cap that has the highest ripple current spec. These caps usually also have low ESR (equivalent series resistance), that means they charge up quickly and discharge quickly under dynamic situations. 
Audio Research Analog Modules
I would also check the main filter caps on that unit to make sure they aren't leaking. Some amps of that era were prone to it. Also check the emitter resistors on the board that feeds the outputs for cracks or open resistors. 
Harman Kardon Citation 22 No Love?
The output heatsink heating up is due to either bad output transistors, too much D.C. at the outputs, or bad bias heatsink transistor. Usually, there is a transistor mounted to the heatsink that adjusts the bias up or down depending on the temp. o... 
ARC SP-8 replacement B+ filters
If ARC has them, get the caps from them. They now use better non twist lock-lytic caps on a special little circuit board so they fit in the board properly. 
Is it worth refurbishing my tube Marantz?
They are beautiful pieces and yes if they do nice work I recommend you get them fixed. The filter caps in the preamp and the amp will need to be replaced. The selenium rectifier on the preamp will need to be replaced as well. The output transforme... 
Mcintosh MC275 vs Marantz 8/8b
Marantz8b all the way. Less tubes in the audio path. Superb output coupling transformer. The Marantz can drive electrostatics like Quads and any speaker with a sensitivity of 88dB/1W/1meter provided you don't listen at earth shattering levels. An ... 
Audio Research M100 Thumping
This is called motor-boating and it means the amp is oscillating. M100's run very hot. Make sure the driver tubes are okay. I believe (from memory) they are either 7119's or 7044's. Those could be problematic. I would suggest you find a place to g... 
Audio Research CL-30 Bias Drift
That's because the bias on 2 of the 4 tubes use a servo. The best way to check that is to wait a half hour while monitoring the tubes that are part of the servo. It has a slow time constant so you will have to wait. If the servo tubes don't pull i... 
Audio Research VSi55 Tube Rolling
You will like the KT-120 
Audio Research VSi55 Tube Rolling
If you can still find winged C 6550's don't use them. The last of the production was not reliable. Apparently the plant burned down and are no longer available. 
Has anyone tried KT150s in their ARC Ref 110?
Nope. I'm not. 
Has anyone tried KT150s in their ARC Ref 110?
Bifwynne please email me..Thx 
Has anyone tried KT150s in their ARC Ref 110?
Nothing yet from ARC. I also noted in the other thread not to use the new (if you can still find them)Winged C tubes as their problematic. Use the 6550we instead.