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introducing the super performance SP14 preamplifier

I am very proud to present my best ever preamp, the SP14


It's been over 10 years now since I introduced the SP14 preamp, and now over 710 sold, about 420 kits and 160 assembled by me for customers, and another 130 by Don Sachs.
This preamp design has not only meant my expectations but has exceeded them by a strong amount - read the reviews at the bottom of this page!!

This preamp is NOT intended for the casual listener. This preamp is for those who are NOT satisfied with a $3000 preamplifier.
This preamp IS intended for those DIY builders who may have already experienced my SP12, or who want the best preamplifier kit available at any price.
This preamp IS intended for those who want a $6000 preamp but who can't afford that. This preamp built as a kit will total under $1100,
or I can supply it custom built and ready to use.

Strong statements? YES! Do I stand behind them? YES!
I have been building, testing, evaluating, and designing tube preamps for nearly 30 years. Up until last year, my products were aimed at the DIY builder on a budget.
But my customers have been graduating from budget projects, and my better products have been attracting the attention of non-builders who want a super preamp at a super price.
So I decided it was finally time to design a cost-no-object preamp. As a lifelong audiophile and electronic design engineer, I have listened to and evaluated MANY high-end products,
and I can tell you from the inside view that a typical $3000 preamp has about $300 worth of parts inside a $300 chassis. The rest is all mark-up and profit, to pay for expensive
manufacturing engineers and production lines, massive marketing and advertising expenses, reserves for spare parts, and reserves for warranty work.

Let's get to a description of what makes this a great sounding product. First, start with a great but simple circuit design that has been proven (my SP12 product).
Now let's graduate to the bigger octal tubes, that were popular at the peak of tube audio back in the 1950s and 60s. The small common 12AU7 tube used in the SP12
w as derived from the 6SN7 octal tube. Tube fanatics that have been around for more than 10 years, or even better, the ones who were around in the 1950s, know that the
6SN7 is a much better sounding tube than the 12AU7. And because they are no longer as popular as they were 30-40 years ago, their prices are very reasonable for the higher quality tubes.
Next, the basic power supply of the SP12 is replaced with a fully dual-mono design. Each channel has it's own B+ and it's own filament supply. This gives better separation between channels
and lessens the load and interdependence. The B+ power supplies are tube rectified (the ONLY way to go in a tube preamp, none of that solid-state hash) which gives a soft-start
and simplifies the design compared to a solid-state design, and it also sounds better! Then the B+ is fed to a voltage regulator for each channel that eliminates all variation
in the supply, and reduces the noise by at least 20db, making for a deep, totally dark background.
The two filament supplies (one for each channel) use ultra-fast schottky diodes, and then the filament voltage is regulated by a low-noise, low-impedance device that is completely
isolated from the audio signals.

Finally, since we aren't worried about high-priced parts, the important signal output coupling caps are chosen by the user. For the standard kit, I'm including K40Y PIO capacitors
For users who have a way to A-B switch inputs on an amplifier, there is an extra set of output connections so that capacitors can be evaluated and compared in real-time.
The most popular option are the incredible (and expensive) Mundorf Silver-Oil PIO capacitors. Every customer who has ordered them says they are worth the price!

since this is a DIY kit, the preamp can be ordered customized to your specifications.
While all of the stock parts provided are better quality, if you want the best, just ask!
We can supply (or you can buy your own upgrades) upgraded capacitors (Mundorf, Jupiter, Obbligato) and upgraded resistors (PRP, Takman, Shinkoh tantalum, whatever).
The B+ electrolytics can be replaced with film caps (Audyn or Solen or Mundorf). Standard Tungsol tubes can be replaced with old Sylvania "chrome domes" or your choice.
Email for a quote on any options or upgrades.

send email to ROY at:

Sorry, no longer any shipping anywhere outside the USA.

Buyers note - this preamp does NOT have a phono preamp section in it - it will NOT fit inside this chassis!

see more photos of the kit build process on the link below (some of these photos are quite old now, will be updated in the future):
here's a custom build by a customer that came out nice!
what comes with the kit? here's a list of "chassis parts"
NEW 2020 build photos #1
NEW 2020 build photos #2
NEW 2020 build photos #3

new 2021 build photos

here are some photos to help you identify the parts to build the SP14
here's a link to the Don Sachs page who builds custom SP14s for premium customers check out HIS reviews!
Here is a link to Don's review

Here's what Don has to say about the preamp . . .

This is the finest preamp that I have ever heard!

Here is a review from August 2015
Hi Roy, I sent the quick review below of Don's production version of the VTA-SP14 earlier this week, right after I got it. 
My delight with it increases day by day! Don did fabulous work on this version of the preamp, doing something to add the bit of gain I needed, relative to his prototype I had for a spell, 
and now it drives my speakers just dandy. I am totally blown away with how fine this preamp sounds and it is dead quiet, which is unique with the tube preamps I have had over the years. 
It is completely 3-D in sound presentation and the LF is amazing. Along with my Linkwitz LXmini's, this is finest addition to my audio system ever. 
Thanks for your great design work and employment of these very fine octal tubes. 
I hope a lot of music lovers avail themselves of this preamp at a price that punishes the over-priced gear out there. 
Mark White Sacramento 
"I got home from work today and the package with the preamp was right where I asked the UPS man to leave it, surprisingly unscathed. I got it hooked up in a jiffy and put on a Vince Guaraldi CD to demo it. You know my test of new components: if I don't hear a clear difference in a minute or so, it probably isn't a warranted upgrade. And I will say that I have been gushing about how much I have been digging the modest Dared tube preamp so that is where I am coming from, but I had the HK C-I and the $4000 Modwright preamp so I do have those as as somewhat distant frame of reference. Well, holy hell, the first measure of the music made it clear that is revealing of music in a way that makes the Dared sound dull and constricted by comparison. The soundstage is immense and 3-D-like. and the bass is deeper and much better controlled. This I heard in the first few minutes. The inner detail is presented, quite exquisitely, really, in a way I don't recall hearing from with the C-I you did upgraded for me and in addition it is dead quiet, which I could not say about the venerable C-I. It seems more detailed than the C-I and less complicated with only 5 tubes, accessible from the top. While I ought not rush to judgment, I can't help doing so with this preamp as it is so much more detailed and extended than anything I have had in my system, and this is with a $350 amp! The roundness of the upright bass player is just at a very very different level than the Dared. This preamp loves low bass notes! I have absolutely no desire to add a sub to the Linkwitz speakers, none at all. The high end is very fine with nary a hint of brightness, which would put me off. This is unquestionably a tube preamp, but it is very quick, detailed and extended. To the issue of gain, it is about as loud as I like it at 12:00 or 1:00 on the volume pot so I have all the gain I need with the external cross-overs and the Linkwitz speakers. The wood case is very nice as is the silver faceplate, nice to look at and very utilitarian. I will be putting it through its paces in the next few days with familiar recordings, but I will say at the moment that this is probably the most significant electronics upgrade I have ever experienced in my audio system. I would expect this performance with an uber expensive preamp (although I did not hear it from the Modwright), so for around $1700, this is a very affordable and pleasing addition to my system. Every claim you have made about the sound of this octal-tube based preamp is just what I am hearing! I am living the dream and I am eager for you to visit to hear your preamp with the Linkwitz speakers. You adroitly figured out the need for the Mundorfs caps to mate with my external cross-overs and I know you put a lot of effort into that process and I greatly appreciate it. I can't see how others would not find the same level of musical satisfaction I am having with it for such a modest price!" Cheers, Mark

here are some reviews of the Don Sachs version of the SP14 from 2016 on the AudioCircle forum . . . This pre tops my most recent units, an ARC LS-25 with full GNSC mods (actually was Steve Huntley's personal piece) and the PrimaLuna Dialogue Premium that I currently own." - Chris A.
"Don's preamp is the quite simply the greatest improvement I have ever experienced in my 45 years of listening to my system."
- Whitestix
"Notes I knew to be there before that barely came through, now sound like I'm four rows back in the center seat at a concert. Right now, it loves anything acoustic. And joy of joy, the SACD version of Dire Straits Mnney for Nothing is mind boggling. I'm hearing things I never heard before." - BlueOne302

We get reviews almost weekly from new owners, here's one that pretty much sums it all up!

Roy, here is my review of the SP14. Feel free to use or not use as you see fit. 
Thanks again for offering such a wonderful audio product !
Ted Rupel

I was able to purchase the best piece of stereo gear I have ever owned this summer, the Vacuum Tube Audio SP14 line stage stereo tube amp, designed and built by Roy Mottram. 
I received it and it is a beauty. While taking off the cover, I had the opportunity to see the care and craftmanship that went into the construction ...absolutely first rate 
in all regards. I ordered the kit assembled and I am so happy that I did. It comes stock with features and parts that are fine to begin with like dual power supplies.  
There just are no "cut corners" in the parts that are used. I ordered the following upgrades;  the  Khozmo premium volume control, Audyn Copper caps, Mundorf  silver-oil 
PIO caps both of which I highly recommend. Also, I got upgraded power supply capacitors and PRP and Takaman resistors in the signal path. My final upgrade which I did on 
my own was to use Psvane CV 181 Mark 11 tubes. The sound right "out of the box" is amazing. I am hearing details I have never heard before or if I did hear them before, 
they have greater clarity. Separation and sound stage are outstanding, plus, the preamp is SO quiet. I truly believe that this preamp beats preamps costing much more in price. 
I know that as the caps and the tubes burn in that it will only get better, but right know it sounds fantastic to my ears and the build quality is so very good. 
Roy is also very good to deal with and will answer  questions and discuss any upgrades you might have.  I would recommend this preamp to anyone in search of a high end 
line stage preamp. You will not be disappointed! 

please read our return/refund policy before ordering

standard version K0
remote volume K1

a complete kit of all parts to build non-remote version K0 is $1100
plus $50 shipping in USA
Chassis parts will be delayed about 2 weeks for shipment
includes all tubes

a complete kit for remote control volume version K1 is $1400
plus $50 shipping in USA
Chassis parts will be delayed about 2 weeks for shipment
includes all tubes

SP14 PCB bare PCB
$99 free shipping in USA
SP14 PCB with parts kit
$279 plus $11 shipping (not including tubes)
SP14 assembled and tested PCB
$379 plus $16 shipping (not including tubes)
SP14 tube set - four new TungSol 6SN7 and one 6X5 rectifier
add $200 to above.
transformer set for SP14
(280vac/100ma, 6vac/1amp, 2X 8vac/2amp)
$80 plus $15 shipping (USA)

assembled, tested, ready to use SP14 K0 preamp, $1550
plus $50 shipping in USA
includes all tubes

email me for an assembled preamp, now talking orders
for August 2022,
one month out

assembled, tested, ready to use SP14 K1 preamp, $1850
plus $50 shipping in USA
includes all tubes

email me for an assembled preamp, now taking orders
for August 2022,
one month out

new special V23-E0

with a 24 step EIZZ volume
assembled/tested special price $1550 16" wide

new special V23-K1

with a 64 step Khozmo remote volume and single blue LED display
assembled/tested special price $1850 16" wide

hand selected nearly NOS Sylvania chrome dome tubes
from 60s-70s era, plus one 6X5 rectifier,

add $220

pure film B+ caps to replace standard electrolytics,
add $60 set of four as shown in photo.

Mundorf silver-oil to replace standard output caps
absolute premium sonic quality
add $95/pair.
MultiCap RTX
high grade polystyrene and tin foil, premium sound for less
$60 a pair

master volume attenuator upgrade (24 steps)

left/right attenuator upgrade (24 steps) $150 a pair

Khozmo premium
stereo 48 step volume control $195

Khozmo premium
pair of 48 step mono attenuators $180

Khozmo remote 64 step volume K1 $295

premium power cord 5 feet $55

RCA-RCA stereo pair 5 foot interconnect $55

check out this link to a review and photos of a recent SP14 with the Khozmo remote
"sounds better than a Pass Labs X1 preamp that retailed for $5800"

a $5000 preamp for $1550 . . . .

Yes, my Vacuum Tube Audio SP14 is a $5000 preamp that I sell for $1850 (assembled/tested/warranty).	
Here I'm going to tell you how that's possible and why it's such a great bargain (if you didn't already know).
I've been meaning to write this for 3-4 years now, but just never got around to it.  But now, here it is.
My Vacuum Tube Audio business is built around VALUE, not profits.

VTA doesn't pay a Chief Executive Officer (CEO) $200,000 a year.
VTA doesn't pay a Chief Financial Officer (CFO) $125,000 a year.
VTA doesn't pay a VP of Marketing and Sales $125,000 a year.
VTA doesn't pay a Director of Human Resources $75,000 a year.
VTA doesn't pay for 4 Electronic Engineeers at $75,000 each a year ($300,000).
VTA doesn't pay for 20 electronic techs (worker bees) each at $45,000 a year ($900.000).
VTA doesn't pay $250,000 a year to rent a manufacturing warehouse
Those figures add up to just over $2 million a year, and those figures are in the ball park for a typical small manufacturing company.
I worked for five companies very similar to that during my 30+ year career.
A company like that might make 1000 pieces of a $5000 preamp each year, for $3 million in sales.  
Yes, that's correct, not an error in math, they sell them to dealers at $3000 each (40% discount from retail), 
so the dealer can make $2000 profit.   So now you see, they make $3 million in sales, and have over $2 million in overhead,
so they are making just under $1 million in gross profit, which is pretty good, around 30%.  
Of course, there are some other overhead expenses I didn't mention, let's not forget taxes and social security 
to the government (around 30%) and of course ADVERTISING, medical, dental,  vision, and retirement funding, 
so now they are probably down  to a profit of around $500,000 or around 17% of sales, right in the ballpark for a decent business.

With VTA, I do ALL of the above myself!   I work out of a  spare bedroom in my home.  I work 40-50 hours a week.
VTA pays the IRS and social security taxes of around $10K a year.  

That $5000 preamp that dealers pay $3000 for has about $750 worth of parts in it.   This I know.  In fact,
if you look inside a $5000 preamp you can pretty easily figure the cost.   About the same cost as my $1850 preamp.
My preamp has $1100 worth of parts, $500 worth of labor, and $200 profit for me (about 10%).  I can live on that.
You get the VALUE, not the marked-up price.  I don't have dealers, I don't advertise (just a few free ads on ebay),
I don't have any employees (or worker bees).  No secretary.  Just internet, email, website, buy direct !!
I find the best sources for parts, buy in bulk to get some wholesale pricing, and you get the deal - a $5000 preamp for $1550.

Maybe later I'll take you inside some of those $5000+ preamps and show you where they cut costs on parts quality.
I've seen alot of those preamps using RCA jacks that cost $1 a PAIR.  Chassis cost under $100.
My RCA jacks cost me $5 a pair, and my chassis costs almost $300.

inquire about any other options or modifications you might want via email . . . .

send email to ROY at:


 tubes 4 hifi
 "the path of least resistance is through a vacuum"