A switch for 3 amps


I’m hoping for a solution:  I’m running the usual Frankenstein setup for multiple source playback, CD, streaming, and vinyl.  This hybrid system: tube preamp, SS amp, and WiFi streamer all lead to  1.7i modded Maggies (GR Research).  In the chain is a Schitt Lokius (primarily for digital only). The room is an open plan family room.  The issue is I want to add 2 mono tube amps to the system for moderate volume playback (jazz, acoustical, etc.), but I want to use the SS amp too with a switch to go back and forth from the monos to the SS for different music (prog rock and electronic).   Is this even possible?  I’ve looked and see switch’s but nothing that exactly address my setup.  The room is  20 x 30, 9’ ceiling damped by rug, and heavy fabric furniture.  And, to add to all that, the mono’s are  Quicksilver M60s which are only 60w per, but I got a great price on them and have heard others who’ve used them with 1.7 or 1.6s with good results at moderate volume.  So I want to give it try.  Thanks for your suggestions.

128x128audiodidact

@aricaudio 

Aric at Aric Audio built me one for just this reason. 

Luxman Amp and his 300 b amp.

He put a dummy load just in case I decided to switch bit for forgot to turn the tube amp off when switching. Tube amps needs load!

He built it keeping SQ in mind.

Maybe I'm missing something but I don't think the Luxman will work for what you are trying to do. It is simply a speaker selector with only one amplifier input. The Douk is also not the answer because it is designed to go between the amp and the speaker. You need something that has one source input for your preamp and two line level outputs to go to your amplifiers. Then you need an additional selector to direct the speaker level output from the one of the amplifiers to your speakers. The Douk could serve as the second selector but there is a better way.

+1 for Mapletree Audio. You specify exactly what you want and they build it to your needs. I have one and it is looks nice with a retro vibe, is built solidly, and is noiseless. As @alucard19 mentioned, Al Freundorfer is very helpful and he can build you a switch box that will do everything in one chassis. It isn't cheap but it's by far the most elegant solution. If you explain to him what you are trying to do he will custom build exactly what you need.

When you set this up you should use a consistent turn on/turn off procedure to protect your tube amps. With the amps off, set the switches for the amplifer and speaker output and then turn on the amp once everything is properly switched. As with all proper audio hygiene make sure your preamp is muted when you turn on your amplifiers.

@8th-note, thanks for the heads-up on the Luxman vs. the Douk. My understanding (according to the Luxman promo copy), is that the Luxman can do 1 input for an amp and 3 for speakers OR, vice-versa. I will certainly check again before making a purchase, but like @lak above, I’ve read others saying they too found the Luxman to be able to do multiple amps.

@maxdukecapone: Thanks for the suggestion. The Aric seems like a great solution. I will give them a call to see what they can do.

Thanks to everyone that has reminded me how important it is that I am careful with powering the tubes on and off in the right sequence! Lord knows, I do not want to go through all this just to blow-up the whole GD thing!

Anyone, please feel free to share any experience or awareness of using low-voltage tubes on low sensitivity speakers like 1.7i Magnepans (as I noted above, they’re modded with GR cross-overs), I’ve been using a Parasound A21+, which is phenomenal, but I’m looking to create a more subtle sound for acoustic/jazz music. So, I don’t need the power of the A21+, but I do want to keep it for more dynamic music (read LOUD). So, that’s the point of the switch. Hope that makes sense, but please let me know what you think on that score, and thanks everybody for all the great suggestions!!

@OP , to clarify: You want to switch amplifiers, between (line) pre-outs and speaker (load) outputs of 2 amps to one pair of Maggie’s....Douk Audio "LITTLE BEAR" VU3. the Fosi LC30, NeoHipo ET30...all seem to have sprung from the same source, kinda.....but do essentially the same thing: A or B amp to A or B speakers.....VU is a ’classic touch’, but having owned a tiny box with LEDs’ did that as well as the ’power’ function which was a ’good to know’ thing...

There’s a VU control for that, but wonder if it’s switched between the 2 functions of the meters? 🤷‍♂️

It was interesting knowing that the bulk of ones’ listening levels was at 1~10 wrms, whereas the peaks would briefly peak higher....

At least, getting some specs with the Fosi is easier, mho....

My personal switching routine is somewhat different...

@audiodidact -- concerning your question, about 18 years ago I had Maggie 1.6QR speakers that I powered with rebuilt Dynaco Mk 3 mono amps (60 watts each) and was very comfortable with the pairing.  No problem with volume, though I'm not a head banger.  I had a good sized room (approx 25' X 16') and my typical "serious listening" volume would have been 85 to 90 dB.