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Proprius Monoblock Power amplifier
Graham Slee Proprius Monoblock Power Amplifier.
The Proprius is much more than an audio amplifier — it's a most incredible sounding high fidelity amplifier you've simply got to hear!
The Graham Slee products that we sell are a bit special. They are all hand made to order in the UK and individually tested - there is no batch testing! You know you will be getting a very high quality piece of kit that will give you a feel-good factor every time you switch it on!!!
Graham Slee Proprius Monoblock Power Amplifier
Clever-Simple-Reliable Value-For-Money Power
If you "applaud value for money products and clever simple designs that work reliably year after year", these are the amps for you!
The Proprius monoblock power amplifiers will each deliver a continuous 25 rms Watts into 8 Ω and 45 rms Watts into 4 Ω at less than 1% THD, but will sound a whole lot louder.
They're cute and compact but they're not class-D! They're linear class-AB for a superbly polished sound.
The Proprius is much more than an audio amplifier — it's a most incredible sounding high fidelity amplifier you've simply got to hear!
With volume controls that go all the way, these power amps can be driven by a separate preamp by parking the volume at full — or their own volume controls can be used in a minimalst system driven by a fixed output source.
Clever - Arrange to Taste
As a stereo pair the volume controls can be used to balance the stereo image if there's no balance control anywhere else.
Bi-amping, tri-amping, and surround sound will benefit by using the Proprius volume controls, allowing you to easily adjust the tonal balance and/or audio image placement.
A single Proprius monoblock power amplifier with its outboard power supply
Simple (and Smart) Design
Power amps don't have to be brutish - they can be neat and compact as the Proprius shows - and at only 20.5 cm deep by 5.5 cm high by 10.5 cm wide, the Proprius is definitely neat and compact.
Cool running doesn't always require dark, drab and dusty heat-sink fins - clean lines are possible as the Proprius heat-exchanger case shows. It doesn't overheat even when used for long intervals at maximum output.
Easy to connect and get up and running, the Proprius can be used with "single-ended" and "balanced" sources using the same single input XLR socket (left).
Connect power supply to the "48V" connector - both signal and power connectors are locking - and attach the speaker cable: the speaker terminals accept 4mm plugs; 8mm spades; or bare wire to 4mm diameter.
The Proprius amplifiers can be used free-standing wherever you want, or mounted on the back of speakers, making them into "powered monitors" using the supplied mounting kit.
A Proprius monoblock amp attached to the rear of an Harbeth M20 monitor loudspeaker
Reliability
The last thing we want is to be repairing the things we make - it's so counter-productive.
So that should give you a clue to why the Proprius has a number of features which make it reliable.
Lid's off the Proprius showing its truly linear class-AB circuit
We don't want it to break when you forget yourself, and although we don't advise on you being wreckless, we did lots of naughty things ourselves to test the reliability of the Proprius.
Knowing we were going to do this, we made the power devices as rugged as we could - yet we also needed them to be gentle-giants to resolve all the subtleties contained in your music.
It means we don't need to employ a protection circuit which is always meddling with your transient highs.
Instead, it's intelligent remote power supply can detect when things are getting out of hand when it immediately shuts down and restarts when the problem goes away. But that's not going to be during normal listening.
And then we added the final "failsafe" - a fuse (just in case).
Specification
Item | Measurement |
---|---|
Power output (rms) measured | 26 Watts into 8 Ohms; 45.5 Watts into 4 Ohms (ref 1% THD+N at 1kHz) |
Power bandwidth at rated power into 8 Ohms | 10Hz - 47kHz (-3dB), 20Hz - 25kHz (-1dB) |
Power bandwidth at rated power into 4 Ohms | 12Hz - 40kHz (-3dB) |
Total harmonic distortion and noise at 8 Ohms | 100Hz: 0.043%; 1kHz: 0.047%; 5kHz: 0.061%; 10kHz: 0.085%; 20kHz: 0.125% |
Total harmonic distortion and noise at 4 Ohms | 100Hz: 0.066%; 1kHz: 0.071%; 5kHz: 0.094%; 10kHz: 0.129%; 20kHz: 0.181% |
Signal to noise ratio in dB | "A-weighted": 87dB; 22Hz-22kHz "Q-pk": 80dB |
Bias type | Class Ab; Bias current: 60mA (approx.) |
Input sensitivity for rated output | 575mV rms |
Short circuit protection | Fuse and power supply shut-down (short circuits should be avoided to prevent component stresses) |
Fuse | F2A 5mm x 20mm (glass "quick-blow" fuse rated at 2A) |
Power supply | 48V DC, 120 Watt - self adjusting to AC mains 100V - 240V, 47 - 63 Hz; IEC cord supplied |
Size (approx.) | Amp W105 x H55 x D205 mm; Power supply W65 H40 D170 mm |
Specifications subject to alteration without notice in keeping with our continuous improvement policy.
Reviews
For an output rating of only 25 watts per channel and being so small in stature I couldn’t believe how loud and good these little amps sounded. My resident Triangle Titus EZ’s are relatively efficient but there was loads of power in reserve and I never felt the amps would run out of steam in my average sized living room. . . The sound is very clean, smooth but detailed and three dimensional. I didn’t feel any part of the frequency range suffered and on a very wide range of music types they excelled in all cases.
Ian Ringstead, Hifi News 2015
Having 'downgraded' from some serious valve amplication costing several times the asking price, the GSP combo didn't sound out-of-their-depth at all. No transistor amp (and only a couple of valve amps) has ever matched the sheer musicality and transparency of the sublime Yamamoto but the Majestic/ Proprius were not a million miles behind, sounding unusually sweet and open for a transistor design and certainly well able to control the bass of the M15 which has a tendency to looseness with many amps regardless of output. The monoblocks, hard against the speakers gave lovely soundstanging with great left-right definition if a little less depth and 'air' (hateful word) than the Yamamoto. Their control, detail and overall lack of grain or other nasties made them both easy to listen to and well able to demonstrate the difference between mixes and different components.
Geoff Husband TNT Audio
This is about music; this is real class Ab – not D or T; this is about ease of listening, and an amazingly good amount of audio level despite the low power numbers; all those sudden bursts that many an amp needs hundreds of Watts in reserve to deliver with any meaning, are catered for with comfort here, even when I connected them to my 83dB sensitivity 15ohm LS3/5a speakers. . . This had grunt, with an exceptionally dynamic and energetic soundstage from the deepest lows to the tizzling tops. . . That this 21st Century £1299 all-in package can sound as good as it does is indicative of Slee’s compulsion with creating the very best. . . This is real class in a pint pot, and well worth the price.
Janine Elliot - HiFi Pig 2015
HiFidelity played an Acoustic Solid turntable with a Hadcock arm into Electrocompaniet amps and to two pairs of Usher Dancer floorstanders. Prototypes of Graham Slee's tiny mono power amps were also on show, which made a very interesting comparison. Despite the EC amps being several times more powerful, the Slees lost no sense of energy and dynamism
Hi-Fi+, Dublin High-End 2012 Show Report
So small may be their physical appearance, so great are their musical charisma and playfulness. Amplifiers must in future be measured in my system with the Graham Slee Proprius...
Hi-Fi Stars, März 2014 - Mai 2014 - Amplifiers Graham Slee Proprius Mono (translated from German)
The Graham Slee products that we sell are a bit special. They are all hand made to order in the UK and individually tested - there is no batch testing! You know you will be getting a very high quality piece of kit that will give you a feel-good factor every time you switch it on!!!You will have to exercise a modicum of patience once you have placed your order! These products can take a couple of weeks to get to you - many are assembled from scratch once you place your order, by a real person on a real bench!! .. but it will be well worth it!!If you have any questions about these products please don’t hesitate to ask us - if we can’t answer, the nice chaps at Graham Slee will save us!!!We sell the entire range here at Phonostage Records and are proud to do so - so enjoy your shopping experience and GO TREAT YOURSELF!!! You deserve it!
EAN | 7626013824926 |
---|---|
Product Weight | 2.00kg |
Brand | Graham Slee |
Model | Proprius |
Type | Power |
Output Channels | Stereo, Mono |
Power Output (RMS Per Channel) | 26 Watts into 8 Ohms; 45.5 Watts into 4 Ohms |
Connectivity (RCA/Optical/Bluetooth etc.) | L/R RCA, Balanced Connections, Banana Plugs, Spade Connectors, Bare Wire Terminals |
Remote Control | No remote |
Colour/Finish | silver |
Warranty | 1 Year Manufacturers Warranty |
Product Width | 105cm |
Product Depth | 205cm |
Product Height | 55cm |
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This Item:
£649.50
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