Single input tube preamp

I'm looking for options for a 1-2 input tube preamp. Space-Tech Laboratory in Canada has the type I'm looking for but I don't know anything about them. If anyone has direct experience with them, please respond. Otherwise, I like to know about similar builders of small, tube line stage preamps. 

Balanced preferred but not required. Thanks for any responses. 


There was a posting on Canuck Audio Mart a few months ago showing the insides of one of his amps - it looked like a bowl of spaghetti with less than amateurish solder work and poor parts quality - a number of tech's weighed in and said it was worse than a boy scout project - globs of solder everywhere, resistors just twisted onto capacitor leads instead of a turret board or terminal strip, household romex used as B+ rails, etc.   The owner then responded with a condescending statement basically saying "if you want it built properly, it wont sound as good".  The CAM moderators removed the post presumably in support of one of their advertisers. I visited his garage in BC where he builds his amps a few years back......lets just say I was less than impressed. 

Linear Tube Audio MZ2 would seem to fit the bill, but you really need to add their linear power supply to get the best from it.



Very interesting. I'm currently using a Schiit Valhalla 2, another OTL headphone amp/preamp in a similar setup. It gets input from my Bitfrost 2/64 and I run it wide open into a Schiit Kara preamp in passive mode. So, there's no attenuation to the tubes and the only volume control in the circuit is the Kara RL volume control. Sounds pretty nice for the cost and is what prompted me to look for something similar.

This look like the perfect upgrade but a new MZ2 is above my budget. Maybe used ones come along. I'll keep an eye out. 

Well executed, high performing simple designs. Add enclosure and attenuator. VTA Roy Mottram's SP14 is based on the same Akido circuit.

There's an LTA Microzotl with two input tubes on USAM in your price range, and it comes with a linear power supply. The seller seems to have a great reputation. (I am not him/her.) That might be your answer. Very solid and well regarded product.

Take a look at Musical Paradise MP 701 MK2. 3 inputs including balanced, as well as balanced output.  Simple volume pot and input selector. Multiple tube options and cap upgrade available. 

Thanks for the responses. My budget is up to $2500. In my search I came across the Quicksilver Line Stage preamp. It's in my budget but another company I'm not familiar with. Anyone have experience with this piece? Or a similar unit from other companies. Final question: How would something like this compare to a used ARC LS25 or similar?  

Once you get to know more about them, the single tube will not be your choice.  There is a Decware Ultra on WTB that will knock your socks off.  but will stretch your budget.

avoid the printed circuit based amps and preamps.  go with point to point. Decware and Aric are top shelf.


The LTA products look perfect. My question now is whether to go with the new Velo or save for the full preamplifier. 

I own a space tech Labs qa112 preamp and super rectifier and a space tech Labs DAC I bought them all used and have them powered up 24/7 for years now and never have any problems with them. They sound great and are very easy on tubes. 

@dwolek perhaps you should look up true point to point wiring on the diy audio forum. There are no turret boards or terminal strips in true point to point wiring. A lot of old electronics equipment was done this way and lasted longer than most modern electronic equipment.

@mashif  In my search I came across the Quicksilver Line Stage preamp.

This is an excellent preamp. I owned this for a while and it's reliable, sounds great. I wanted to move on from it because I heard preamps based around the 6SN7 tube and I like that sound better. But this is a solid choice, for sure.

Quicksilver has been around for over 40 years. Mike Sanders (owner) is a great guy to deal with. I own that preamp and my only beef is that the gain (18db) is on the high side.

Another brand worth looking into is VanAlstine. My friend is using the 10RB and he likes it very much!

Analog Preamplifiers – Audio by Van Alstine (


I was going to wait for the new LTA Velo but I found a pre owned MZ2 at a fair price. Hooked it up today and WOW. What a beautiful sound. Thanks for the input.

Great to hear and congrats! Thanks for the follow up, and really glad it seems to have the power to drive your very efficient speakers. Tell me you got it with the linear power supply.

Yes, got the LPS. Makes me wonder why every high end manufacturer doesn’t do that. Eliminates all the isolation and heat issues.
I’m not driving speakers, I’m driving a Parasound A23+. At the moment I’m going through my passive preamp with remote volume control. I’ll connect it directly later on and see if the passive is hurting anything. Keep you posted. 


A little follow up. I upgraded the original RCA 12SN7s with some NOS JAN Sylvania VT-231/6SN7s from the great folks at LTA. They're sounding better every day. 

After getting a remote, I went directly from MZ2 to A23+. To have enough play on the LTA volume control, I had to use the volume pots on the amp. So I essentially swapped the volume control on Kara for another. After a couple of weeks, I've switched back to running the MZ2 through the Kara with better results. I think the RL volume on the Kara is cleaner than the volume pots on the A23.

So the amp runs with no attenuation, the Kara provides resistor based attenuation, and the MZ2 volume control is just right. I can always run the Kara wide open and only have the MZ2 volume control in the chain but I think the gain structure is better with some attenuation. I can also put the Valhalla 2, or a vintage pre without remote, into another input for another flavor. And I have the SS functionality on the Kara for non critical listening. I like it.