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A little tube magic?

I’m looking for some ideas and impressions. I’d really like to run tubes for amplification, but my system pulls double duty for music and tv. It is on probably about 8 hours a day for one or the other.  This just seems like to much to me for running tubes. I’m looking for a way to be able to keep my solid state setup but add tubes in a manner I can switch them in and out. I have couple of ideas but I am aware neither is very ideal. 
First I thought I could add a tube preamp or maybe even buffer in the tape loop of my McIntosh C46. I know this will add more complexity for the signal to pas through. I’m not sure if I can expect gains that will be better that what I lose by adding extra cables and components.

My second idea would be to add a tube power amp on some sort of switch, something similar the the Shiit SYS. Which is basically a passive preamp with two inputs and a potentiometer. I’ve read that can use it backwards kind of and have the output be the input and run the two inputs to two different amps and then switch between the two. I would think I’d need two sets of speaker cables to make this work, and switch them back and forth as needed. I’m not really fond of either idea and hope there may be a solution I’m unaware of. I really just want tubes for music and ss for tv if it’s possible.  
A third option would be to get a tube dac for music listening, but I’m unsure if I’ll be able to get the amount of tube sound I’m after. I guess I could see it as part of the solution along with tubes in the pre or power amp as well. 
Any thoughts or ideas would be much appreciated. 
brylandgoodman
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mwh777
71 posts
 
The following is what I'm doing right now for the exact same issue, millercarbon's eyes will be rolling soon I'm sure (don't get me wrong, I thoroughly enjoy MC's presence both for the experienced perspective and the entertainment value provided for free, thanks MC) .

I have two preamps in my system. The tube preamp is for music and for tv and other video is a solid state preamp. My amp is solid state. Access to the back side of my equipment is easy. I simply power down the amp and move the interconnect that is between the preamp and the amp from one preamp the the other as needed. Yes this is not ideal but, is easy.

There is one difficulty to be faced and that is overlap of remote control commands between the two preamps. Most manufacturers use some variation of the Philips remote protocol (japan makers use the NEC protocol). I get around this problem by placing an inexpensive metal bookend (Amazon sourced) in front of the remote receiver eye on the preamp that will not be in use at that time to block the remote control signal.

Yes I wish I had a more elegant solution but this does work. I tried the home theater bypass idea by feeding the tube preamp through the bypass circuit in the solid state preamp but, the HT bypass was not transparent enough to work well.
russ69's avatar
russ69
3,360 posts
 
"...It seems it could be pretty expensive swapping 6+ tubes on the regular..."

A legit concern, you could go broke running 5 channels of tube amps. My opinion might not be popular but you can run a good 2 channel system for music or you can run a multi channel system for video. Doing both really well is a GPIA. 
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oldhvymec
5,101 posts
 
mwh777, if you go the other way you might have better result. Bypass through the tube preamp vs through the SS. I just had to work out the bass management system for both systems without plugging and unplugging. I used a C2500, MX150, Rogers PA-1 and 124/SME, same crap with the remote. Mac is easy to assign stuff.

It’s as transparent as a preamp with tone control, a power amp and source with cables and speakers can be. Oh, oh I forgot the phono stage or streamer with a transport. I say color me slightly.. :-)

I run Carys V12r / Six Pac or Macs 240-275s, at least 70 hours a week in the winter for 3 months, spring and fall I remove 4 valves at a time and re bias (Cary only). Mac I use only in the dead of winter or in the shop. It gets HOT where I live, I swap to SS Class Ds for 3-4 months through the summer in the front room (wife’s system).

I’m looking for a second V12R in red. :-) KT66 or 77 are just the 11th wonder of the world in that unit. 4-12 valves, you just have to bias it for the number of valves.. 6V6-KT99s.

Cost;

I picked up 8 6V6 Rubys for 75 dollars. They will last 5 years in that V12. Brand new in the box test as 8 matched new valves... 6550W black plate 190.00 for 6 I think..  They use them in Migs for god sakes.. :-) Russian Valves..

Regards
jbhiller's avatar
jbhiller
1,361 posts
 
What's your budget to make a move?  It sounds like the unit you introduce will be doing double duty on music and television.  Do you watch television with just two channels now?  

I would think the advice above about looking at a tube preamp would be spot on--if you don't need to do home theatre/multi channel stuff. 

If you want big holographic soundstage and bloom, try the Vincent SA-T7 preamp.  It's superb.  Somewhere between Conrad Johnson and Audio Research, but that's painting with a wide and fat brush.  There's a used one for sale (Not my listing and no affiliation) here now: 

https://www.audiogon.com/listings/lisad395-vincent-sa-t7-tube-preamplifier-w-remote-manual-box-tube

brylandgoodman OP
83 posts
 
Budget would be around 1,000-2,000 if I were to keep my current ss pre. If I’m replacing it then budget would be 3,000-4,000. Really would like to stick with McIntosh for the simplicity of operation for the wife and guest. Which leaves me feeling like the tape loop may be the way to go since I don’t really dig McIntosh tube preamps from my experience. I think I would be ok with a slight loss of transparency, slight. Not sure what to expect with the tape loop though. I do like that it would be a simple solution without disconnecting and reconnecting. 
I do watch television with just the two channels.  I’ve never really had much interest in surround sound. If I was building a new house I may incorporate it, but not very compatible currently with out a lot of Sheetrock work to run cables. I’m pretty sure I hate Sheetrock work more than I would like surround sound. 
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