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

Dock audio VU 2 for $189 will do the trick. Read reviews. May want to add a different power supply. 

Thanks!  I looked at both the units and the Luxman looks to be pretty solidly built, but dated, while the Douk is a newer and a great price, but less sturdy looking.  Lak, have you personally used the Luxman?  I wonder if it delivers better for the roughly $450-$500 price tag. Thanks again to you guys.  

I know nothing about the switching options offered, but one needs to be careful with most tube amps -- you shouldn't remove the speaker load when they are turned on but not in use. An option would be to have them switched to a suitably sized (ohms & wattage) when not connected to the speaker.

Go with the Luxman AS-55. It uses heavy duty switching contacts which never get "dated". Most switches are rated for DC voltages, which is why a flimsy looking switch can be rated for (DC) 10 amps -- but pass a 10-amp AC voltage and it arcs the contacts. You don't find many 2-pole AC selector switches that can handle 20 amps, like the switch Luxman uses.

Do you mean that I should not turn the tube amp on with the speaker off? Or vice-versa? I think I do get the idea that tuning the tube amp on and off willy-nilly is never a good idea. Also, can I use a 12v trigger to the tube amps connected to the preamp so the tubes and preamp come on together, or no, don’t do that either? I know the foregoing may sound pretty ignorant, and that what I’m trying to do seems, even to me, to be kinda insane, but, maybe good, if I can pull it off without blowing-up everything?

I see I made a typo in my prior post that didn't say things as clearly as intended. Don't power on a tube amp with no speaker connected, though it is acceptable if you use a suitably size resistor in place of the speaker.

You can try  Welcome to Mapletree Audio Design

you will want the SCC1 system configuration controller, I had one made for me custom, by Al Freundorfer  [email protected]

I use it to control 2 tube amps, a CD player, and turntable hooked up to 2 different sets of speakers. I can switch from either amp to one of the sets of speakers, I can have both amps on and switch back and forth to the speakers to hear which amp sounds the best with what music I am currently listening to from either the TT or the CD player. it ran about $450.00 USD 2 years ago, just email Al and tell him how you want it configured and he wil quote you a price then build it for you.

I have an SET Class A Tube AMP and a Marantz SS amp connected to a Douk Audio "LITTLE BEAR". It can also drive two sets of speakers too so you have up to 4 amp/speaker combination. Key is the Little Bear presents a LOAD to the tube amp even if not selected. Some tube amps require that to be powered on. Been using it for two years with zero issues. Now, Amir at Audio Science Research poo poo’s this unit due to noise but I am thrilled with it.

The Luxman speaker selector switch mentioned above appears to drive 3 pairs of speakers on one amp ?  Not familiar with it and I can't any manuals to confirm it can handle 2 pairs of amps....  

@audiodidact I own and use the Luxman AS-55. It is solid and works well. Could be used for three different amps or one amp and three different pairs of speakers. Shop around for your best price.

@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.

@mlsstl —That sounds really encouraging.  My  1.7is really are not very different in impedance and sensitivity from your old 1.6QRs and the fact you ran them with 60w monos successfully is music to my ears.  I generally listen in 75–85db range, not so loud, though when I want to be crazy I will turn it to 90db max, depending on the source material.  I’ve modded the Maggies with new crossovers from GR Research and with my SS amp, the 400w 4ohm Parasound A21+ , the Maggies can really sing as loud or as quiet as I want. So,  I’m hoping that, as a result of the improvement the Maggies will be even more accepting of the lower watts from the tubes.  We’ll see. I will keep the Parasound and add the mono tubes with the Luxman switcher…unless, the Quicksilvers deliver a better sound at “serious” listening levels.  All the amps will feed into a Prima Luma 300 preamp which as sold me on tubes. In fact,  I’m so sold on tube monos now that if the QS can’t rise to the occasion, I will just save a bit longer and get higher wattage tubes.  This is all new territory for me so I’m very grateful for all the input!  

Lucky for you I have been down this rabbit hole and search to the depths of Google far beyond I ever imagined.😁 I have found a whole bunch of solutions for your exact needs. However I am going to list all the ones I have found and you can pick out which one you feel is best for you. The one I like the most out of all of them is a company from Europe that will custom make exactly what you want based upon your needs. Rather than try and fit in your requirements to a pre-made box you have a box made for your requirements. 

 

This was the first stage of a setup for me and now I am looking for a digital version that will run USB to a USB switcher source and that is a whole another mess I am running into but that is a whole nother set of problems for me.

#1 Choice, they will build whatever you needTake a look around at site it's pretty fun​​​​​​​ their products.https://vintagemaker.net/

A lot of these are XLR but you can get component or RCA to XLR cables and I suggest to use Amazon and don't pay for anything expensive as it will not make the quality any better.

#2 LinkBone 8×8 Matrix XLR switch

#3 Black Lion Audio PBR XLR Patchbay\

#4 4 In 1 Out Stereo Audio Switcher Switch Splitter Selector Balanced XLR Interface Remote Control VFD Screen

#5 Kramer VS-4X 4x1 Balanced Stereo Audio Switcher (XLR)

#6 XMSJSIY 6.35mm/3.5mm Audio Selector Switcher 6-in-1-out

#7 Nobsound 3-IN-1-OUT XLR Audio Switch

 

@audiodidact Did any of the solutions I mentioned fit your needs. I haven't put together my audio room yet but one of those options are going to be in my audio room and it's more than likely going to be the vintage maker as I think I'm going to go with something custom made for me. However there is a lot of decent Solutions there from cheap to expensive. But I do like the vintage maker and he can custom build me what I need. 

I'm more or less need the same thing but for a USB in and USB out I don't know if this guy can build what I need but I might try him for it. Not sure cuz I'm looking for something pretty special to you and have not seen what I want so getting it built might be an easier way but basically I want to be able to choose which USB source and choose which USB DAC. So I would be able to pick between 5 to 6 different sources and choose between five to six different Dax or apps to send the signal to. 

 

I'm going to keep an eye on this page and see how you make out with it please keep us up to date there's not too many forums where I've seen anybody really do what you want to do and what I want to do. A lot of people just kind of abandon the forum post's and never follow through with what happened afterwards. I figure there's probably a lot of people searching , Well I know there's a lot of people searching and so far actually I accumulated the best list of switches for amps. 

 

Now I think it's just a matter of me and you and other people trying them out and finding out what works best.

Thanks everyone, for the great suggestions.  I went with the Luxman AS-55.  Works like a charm.