Graham Slee Solo Ultra Linear Diamond Edition headphone amplifier

Graham Slee Solo Ultra Linear Diamond Edition headphone amplifier

"It might look fairly simple, but this Diamond Edition headphone amplifier sounds like a real gem. Vocals are dripping with detail and realism, while the supporting instruments are worked effortlessly making them easy to discern. Bass is deep, well defined and integrated into the rest of the frequency response "1

"This amplifier is a work of art, which significantly outclasses what we would assume possible from the very modest asking price."2


Graham Slee Solo Ultra Linear Diamond Edition headphone amplifier


Product Info


The Solo Ultra-Linear Diamond Edition headphone amplifier gives you the sound you've always wanted from a headphone amp! It enables good headphones deliver lifelike, dynamic and breathtaking performance with a real 'out of head' three-dimensional stereo sound stage.

The Diamond Edition Solo Ultra Linear headphone amplifier has a lower noise floor for improved in-ear monitor listening and a new output stage for better performance with difficult and low impedance headphones, yet it has the clout to drive high impedance headphones too.

The Ultra-Linear voltage amplifier stage gives you the smoothness and warmth of a tube amp, yet with all the precision, fine detail, low-frequency tautness and visceral quality of a world-class work of art solid state amp that it is. Plus, it won't wear out like tubes.

Here is what reviewers are saying:

"This [review] would have been impossible without the Graham Slee Solo Ultra Linear Amplifier. This amplifier is a work of art, which significantly outclasses what we would assume possible from the very modest asking price. I am absolutely stunned that a large corporation hasn’t offered to give Graham an extraordinary amount of money for his amplifier configurations. With the Graham Slee Solo Ultra Linear amplifier in the chain, the dynamics and musicality were presented with such a rich tapestry that it was often difficult to believe that a valve based amplifier was not somehow in the chain." 2

"The Ultra-Linear allowed me to relax more into the music, and appreciate the texture of the instruments and voices. More significantly, the imaging felt more three dimensional and realistic. The frequency response seems pretty much the same, with a very wide extension at both ends, but the treble is sweeter and the bass end has more presence... the Ultra-Linear sounded more musical." 3

"I really can’t forget how I fell in love with it... I recommend Solo Ultra Linear Diamond edition for you if you like Classical music but don’t want your amp to sound bad in other genre of music, Solo Ultra linear Edition should be in your top buying list."4

Original Thinking Reproduces Music So Precisely
While other headphone amplifiers follow the one-way trend of being tuned-up mini-speaker amplifiers, the Solo Ultra Linear headphone amplifier uses original thinking to take the headphone-specific Solo concept even further, so it reproduces music so precisely it naturally sounds more musical!

The Solo Ultra-linear headphone amplifier lets the music flow - it's timing is second to none. The bass is full but never loses control. The highs are free of grain and harshness. Stereo imaging is the best it can be without artificial cross-mix or width extension. Made for the best signal sources - the Solo Ultra-Linear headphone amplifier will be your best headphone amplifier purchase yet.

The Solo Ultra Linear headphone amplifier is a J-FET input - discrete transistor output-stage design which uses open-loop gain and bandwidth modified operational amplifiers that mimic valve/tube performance. The result is linearity in all areas that can only normally be provided by valves/tubes. However, the Solo Ultra-Linear headphone amplifier can directly drive low impedance headphones - as low as 5 Ohms - as well as high impedance headphones.

It also includes our proprietary headphone load feedback network which cancels much of the Solo Ultra-Linear current drive output impedance as well as controlling headphone cable capacitance and inductance so you should never need a cable swap to hear your headphones at their best.

The headphone load feedback network also makes it possible to swap from high to low or low to high impedance headphones without much change in volume control position or the need for a gain switch which could otherwise colour further the music.

Note: The Ultra-Linear technology mimics valves so closely that there is also a similar amount of the valve artefact "hiss". Although this will not be a problem for most listeners because it is no louder than or different to what you'd get from actual valves, if your preference is for the utmost background silence then we recommend the Solo SRGII which is more than half as quiet.

Graham Slee Solo Ultra-Linear Headphone Amplifier Specifications
- Headphone impedance range: 8 to 2,000 Ohms / 16 to 600 Ohms preferred
- Power output: (rms, both channels fully driven at 1% THD) 32 Ohms: 140mW/channel; 600 Ohms: 30mW/channel
- Input sensitivity (for specified power output into 32 Ohms): 511mV rms
- Input impedance: 37k Ohms at max volume; 50k Ohms at min volume
- Distortion: (THD plus noise at 9 o'clock volume control setting (qtr power)) 10Hz-20kHz: better than 0.04%; 10Hz-1kHz: better than 0.02%
- Frequency response (±0,-3dB) 10Hz - 35kHz
- Output noise: (22Hz-22kHz, quasi-peak/un-weighted) -78dB
- Channel balance: better than 1dB
- Crosstalk: Left to Right -56dB; Input to Input -68dB
- Input selector center-off position: non-shorting; -38dB at max volume with 2V rms input (ref: 1kHz and 10kHz)
- Output Stage: Bipolar class AB
- Supply voltage: 24V DC unipolar
- Size: (approx.) W: 107 x H: 50 x D: 185 (mm) inc. controls

Footnote 1: Hi-Fi Choice, "Graham Slee Solo Ultra Linear DE," (March 10, 2016)
Footnote 2: Zardon, "Grado PS1000 Headphones & Graham Slee Solo Ultra Linear Amp Review," Kitguru (March 2011)
Footnote 3: Phil Gold, "Graham Slee Solo SRGII and Solo Ultra-Linear Headphone Amplifiers," Canada Hi-Fi (August/September 2011), 28.
Footnote 4: SU, "Graham Slee Solo Ultra Linear Diamond Edition", Earmass (August 25,2013)

Customer Reviews