Micro Tube DoubleDrive


The Micro Tube DoubleDrive is a high quality tube preamp, built around two subminiature preamp tubes.
These special purpose tubes were developed by the military to operate smoothly under extreme conditions with maximum life span.

The tubes unique expressive sound qualities come alive in this dual/triple gain stage design inside a footswitchable stainless enclosure.
Their wide frequency range and lively dynamics distinguishes them from the more common 9 pin tubes.

The DoubleDrive has two gain stages and a switchable third (Drive). It can be set for clean boost or pushed to produce overdrive/distortion at the output.
The Poweramp output has enough gain to drive a power amplifier directly.
The Preamp output is attenuated to not overload the input of another preamp.

While the DoubleDrive can add much to a signal, the original quality and feel of the signal is retained.
Pure transparency, musically enhanced!

Micro Tubes (subminiature) - Small size, but sizable warmth, presence, power and transparency.
These special purpose tubes were developed by the military to operate smoothly under extreme conditions with maximum life span.

Volume Boost - Overdrive - Distortion for Guitar/Bass

Directly drive a poweramp

Add another preamp channel to your amp

Acoustic Guitar or Microphone preamp/equalizer

Tube Line Buffer

Plug directly into a mixer or recording device

Enhance any signal with real tube power

NEW - Latching power supply connector

55dB voltage gain
Preamp and Poweramp Outputs
Super quiet power supply and
custom transformer
Shock-mounted tubes
Tube life: 30.000+ hours!
Paper-oil capacitors
Carbon Composition resistors
100% True Bypass
16 gauge brushed stainless steel
100/120/220/240VAC (50/60Hz)
Handmade in USA

High Voltage Power Supply included
with adjustable power to tubes

Guitar, Bass, Acoustic, Microphone, Keyboard, Steel ...

Volume, Treble, Middle, Bass, Drive, Gain
True Bypass, Drive On/Off

Input, Power Supply, Poweramp Out, Preamp Out

Latching power supply connector

High Voltage - Zero Hum - Power Supply

Vintage Guitar Magazine Review

User review 1

User review 2

User review 3

Online discussion forum

User Feedback:

Mike DeTemple Phone Message about the DoubleDrive

DeTemple Website

Hi Chris...

Well my Double Drive arrived safely & I am extremely happy. It has completely exceeded my expectations in every way.
For the first time in my life I feel in control of my sound- & what a sound!!!
It really is beyond superlatives; warm, round, clean, defined, dynamic & musical !!
- All the glowing praise from reviewers is completely justified & my little leap of faith in ordering 'sound unheard' has paid off big time.
I feel extremely fortunate to own it & very much appreciate the magnanimity with which you make these (affordably!!) available-thank you.

Novak Conrad

Hi Chris,

Don't worry... I'm not a chatty guy... but I have to let you know that, in a live gig setting, the DD blew me away last night...
I've primarily used the same power amp/speaker combo live since 1990 (just the power section and JBL-E130-4 of a '70's Webb amp [transistor but very nice clean power])
w/ several preamps, and smaller amps w/ attenuators, etc., but the DD blows them all away, including the Avalon U5, and other high end tube pre's.
The only tube power amp that I have right now, which I can plug directly into, is a single ended EL84 (effects loop of a MacIntyre head),
and the DD iworks amazingly beautiful w/ that in my studio... very much looking forward to recording with it.
I'll be in touch when I'm ready for the Midnight Blues custom power amp.

Thanks again,

We fired that baby up last night. Superb. We used it with a Morely wah, a DVM compressor and an Orange amp...absolutely beautiful.
We played around with sequence and using it on its own, in tandem with the others and then with all of them...it noticeably improved everything...I truly love it.
We also through in a Brunetti Vanilla pedal. Your pedal will be seeing quite a bit of action. Great work Chris.

Btw...My friend who works with me to get great guitar sounds is loving your double drive...it's the one piece he refuses to do without in every chain...
I've never seen that before...wow...he's getting me some amazing sounds...while he loves the different guitars and amps....the common denominator is now your pedal...
can't thank you enough for helping get us to the next level...

The Double Drive saw more action yesterday...it seems to like all amps...often pedals can be a bit finicky.. Linked it with a JMI Tonebender,
then tried a Big Muff Pi and the Moogerfooger delay...Got some great sounds...the DD just gives you that edge.
It can even do a great job dialed down... like you don't know it's there but take it away and you know it isn't there kind of thing...very cool...
like salt and pepper in certain recipes. We love it!

Rob Sherr

I am little late letting you know, but I received the Double Drive. It is wonderful. You obviously place a great deal of pride in what you create.
It seems to be built so well, is classy looking, and sounds great with the Nord keyboard I have. It really brings the Rhodes, clav, wurly, and organ sounds to a whole other level.
...and the crunch you get from the drive is infinitely better than the onboard amp simulations on the Nord. Such a great product!
I am still in the process of experimenting with and familiarizing myself with the Double Drive, but I just wanted to let you know how much I am enjoying it, how next level it makes things sound,
and say thank you for answering all my questions along the way. ...hope you don't mind, but I am sure I will have a few more questions as I continue to optimize my use of the Double Drive.

Michael Cetrangol

Wow Chris. Wow. I've had about 100 superlatives and metaphors and phrases of grandeur run through my mind in the past 30 minutes.
Whatever it is that you do, see to it that it keeps getting done.
My amazement is unraveling years of routine expectations and habits from the front to the back regarding everything guitar, music, and amp.
If this preamp is this, then what on Earth are your AMPS??

I love the adjustable power supply, I've barely even played with it yet but seems great for dialing in just enough headroom for whatever situation you're in or mood.
Down low is super nice, so is up high. Can't really go wrong. I didn't think I'd like low that much based on operational description.

The whole thing flirts with a sense of attack that is both guttural and fleet footed. Balance across the board in every dimension. Simplicity is elegance is what you have on your site. This is the most certain embodiment of such philosophy.

I've never just plugged in to something and thought 'That EQ is perfect straight up - check'. I can hear my pickups all the sudden.
My speakers and power amp section are wonderful! So is my source!
My preamp must have been a big weak link for me, I had NO IDEA how much it made everything sound the same. This DD box speaks directly to my existence and musical expression from the well waters of my soul though.

I don't really feel like I need a compressor running into this thing. EASILY EASILY EASILY the most musical bang for buck I've spent.

I can't wait to get this back with the amp for another reamp session. If they thought I did a good job last time this will blow the door open.
I really don't know what to say but it's been a pleasure thus far working with you on speakers, preamps, and knowledge/learning and a big thank you to you for what you're doing. I really don't know where else this would be possible or from whom.

What an explosively musical expertly crafted implement. You sir may be on to genius, that or I just really really really agree with your work and sonic taste profile.

Also in person this is SO nice. I love the font and the knobs and the switches and the mesh. The brushed stainless is choice and those feet give good stability and clearance. Power supply and locking connector mechanism is really nice. I can't wait to dig in more with this. I feel like I've discovered an audio treasure.
I'm a very fortunate man and musician. This is some quality stuff.=


If you've ever used a master volume amp and utilized even the best of preamp distortion you know it can be a little edgy and grindy and lack depth. Somehow the micro tubes, power supply, or design allow these MICRO tubes to have a response that is neither here nor there but very pleasing.
You don't get the walloping power of a power tube, but you don't get the annoying characteristics of the preamp tubes either. I don't know how this is accomplished, nor have I figured out all the complexities of this pedal since I've had it. It is so simple yet so much to discover.
You always feel right at home but never limited. That's masterful work, perhaps it will always be a mystery forever and ever because it is a tool that allows one to focus on music and playing which is constantly evolving. In two years it has stood up to my highest standards and against all other gear being equivalent or better.

I've also tested it and found the impedance to be quite low compared to other units that push the signal along. Despite this, when it hits the amp it does not feel like a hyperstatic super low stale impedance from a typical circuit. It feels more amp like.


Played around until 4:00 AM with guitar and pedal board last night. Your pedals just stand out. They make my fingers go crazy with all kinds of music itís amazing how it just brings it out.

Trace Hamrick

Hi Chris!

I got the Double Drive! It's really good! At first I had to figure out how to get it to work with my little transistor combo here in the appartment, because it has so much output it was pushing it into bad distortion. Then I figured out how big the range of the Double Drive is - you can turn down the volume almost all the way and lowering the signal strength, without losing tone at all! So impressive!

It sounds really good at the moment I like playing my nylon electric into a semi distorted fusion kind of sound on the amp, and the Double Drive is so perfect, the harmonics jump out even when it is not set for distortion at all, really good for clean tones as well!

The trim pot on the power supply is incredible, at low setting it gives a great vey old sort of rambling distortion reminding me of the amps from the 1940s and 1950s that I hear on youtube, and its compressing so nicely.

The build quality is amazing, the thing as a whole is a work of art. I was looking at your gear for a long long time already, now a proud owner of the Double Drive finally!
Thanks for all your dedication and work that you put into your instruments, they are amazing!

- Christopher Pollhammer

Sound Samples:

Review and Sound Samples by Dimitrios Hatzisavas from Gearslutz.com

DD Review

All guitar samples are recorded with two mics (m88 where cone meets woofer and a 57 at 45 degree angle).
Fender strat with motor city afwayu bridge pickup and guitar fetish lil killer neck pickup.
The amp is a laney lionheart 5w. Mic preamps are a pair of EISEN audio neve-ish (amazing pres). There is no level matching in comparison clips. Bass clips are played by Dan Edinberg.

CLIP 1 - double drive clean
CLIP 2 - double drive bypassed
CLIP 3 - double drive overdrive - a little arrangement with two guitars and bass. Bass is a ken smith 5 string recorded direct through my custom double drive (extra features)
CLIP 4 - Distortion. Double drive (stock) used as a booster after a boss metal core pedal
CLIP 5 - Distortion. Double drive (custom) used as booster
CLIP 6 - Distortion. Double drive bypassed
CLIP 7 - Bass direct through custom double drive. Schecter stiletto 5 string. (the noise that you hear is some bad RF...working on it)
CLIP 8 - same setup as Clip 7