[mrarroyo]

At 2:00 pm I called my building concierge from the office. He informed me I had a package

Well I rushed home (45 minutes to drive 34.6 miles in the middle of the Miami and Fort Lauderdale rush hour).

As I picked up the package I got worried. The idiots at Customs had used a razor blade to open the top and had barely used enough scotch tape to properly seal the box. As you can imagine I was worried they had scratched the unit or similar. The good news is that S/N 24 arrived without any blemishes.

The first thing that struck me when I unwrapped the amp was the overall quality of the unit. Housed in a silver anodised case with screenprinted graphics, the amp looks like it's built to last. The front fascia is fitted with a source selector switch, a volume knob and a headphone socket. The fit and finish is superb. There is an obligatory LED indicating On / Off.

The rear panel of the amp is fitted out with gold plated quad PCB mount phono socket assemblies and the power in is a 2.5mm SWC (switchcraft) DC socket. . The feet are small transparent sorbothane types and I feel these could be a lot thicker / wider as they really don't provide a firm footprint for the amp, especially when using heavy interconnects. This is a small gripe and it's easy enough to replace the feet with something a bit more substantial.

Here are some pictures, please click on the thumbnail to view them full size.









The dimensions / physical appearance of the Green Solo are identical to the Solo 2007 but the specifications have changed:


Specifications


- Power Consumption: Max. 3.6 watts; Average. 1.5 watts; No signal. 0.6 watts; PSU only. 0.3 watts

- Headphone impedance range: 8 to 2,000 ohms - 30 to 300 ohms preferred.

- Power output: (RMS, both channels fully driven) 32 ohms - 125mW / channel; 600 ohms - 35mW / channel.

- Distortion: (THD plus noise, ref 1kHz) 0.02%

- Frequency response: (-3db, 32ohm load) 10Hz - 75kHz

- Output Noise: (20Hz - 20kHz, CCIR quasi peak) -83db

- Output impedance: (driving impedance) 33 ohms

- Input sensitivity: (for specified power output) 775mV rms

- Gain: 15db

- Channel balance: better than 1db

- Crosstalk: Left to right -57db; Input to input -68dB

- Quiescent current: (output stage) 7.5 - 10mA per channel

- Supply Voltage: 24V DC

- Size: w: 107 x H: 50 x D: 185 (mm) inc. controls

- Complies with: ROHS, WEEE, E-Waste, CEC, CE, CSA, UL (cUL and UL listed power supply), TUV

- Weight: 600 grams

Warranty: Standard 2 year warranty against defective parts or workmanship.

It took me a few minutes to decide which song and method to play it. Also I had to decide what cans to use for that initial "performance". As many of you know I listen mostly to Jazz. To that effect I chose Waltz for Debby by Bill Evans Trio.

I made a choice to feed the amp via my Apple Losses files in iTunes. I fed this via an optical cable to the Musical Fidelity X-Dac V3 (stock) then I used a pair of RCA to RCA cables by Blue Jean Cables to feed the Green Solo #24. For that initial "performance" I chose the AKG K501.

Why the K501, well since a lot of its owners complain about the bass I kind of use it as my "litmus test" when I test the bass output of an amp. I also read the bass out of the box needs time to improve. Heck the instruction sheet included says so (at least I interpreted it as such).

Frankly I do not agree, I find the bass out of the box to be there and very clear/detailed. Of course it will improve with "burn in" or so I expect. The highs are clear, and detailed. For example when the drummer hits the hi-hat you can hear the impact as well as the closing/opening of the hi-hat.

I will say that to me the best attribute is the amps soundstage. It is very easy to spot the instruments and most importantly the people talking and laughing in the background. For those who have never listened to Waltz for Debby it was a live recording and you can indeed listen to the clapping, laughing, coughing, etc. This amp makes it very easy to place them.

Next I chose Body and Soul by Billie Holiday.

Not only do I continue to be amazed by the placement of the instruments but most importantly that sweetness and intonation in the voice of Billie Holiday comes right through.

As you can surmise I can only expect this amp to get better and better with burn in. Do not be surprised if I start selling some of my favorite amps.

Of course I will let it burn in over the next few days to see how much better it gets. As I understand it Graham Slee recomends 3 weeks of burn in as optimum. I will keep you all informed.

Before I stopped writing tonight I switched over to the Grado RS-1. Very few SS amps can drive the Grado's with authority and wile retaining their liveliness. I am happy to report the Green Solo is one of them.

Note: The term "green" is because this amp is built using lead free solder and it meets the European RoHS (See: http://en.wikipedia.org/wiki/RoHS)

 

[Asr]

Most excellent, looking forward to impressions!

It doesn't look green, why's it called "Green"? And what's with the 2008 moniker, is this newer than the current product? Is this now available or just a beta/prototype?

 

[d-cee]

Quote:

Originally Posted by Asr /img/forum/go_quote.gif Most excellent, looking forward to impressions! It doesn't look green, why's it called "Green"? And what's with the 2008 moniker, is this newer than the current product? Is this now available or just a beta/prototype?

it's called green because it's environmentally friendly and uses a switch mode power supply designed to comply with some new regulation designed to reduce power consumption, so regulated power supplies are out

it's 2008 because the product is a prototype and is not yet due for release until 2008 when the new laws kick in

 

[Zorander]

Nicely written. I agree with your statement on the amp's soundstage (which to me paints a very real picture). Similarly I find the Solo to have great synergy with AKG phones, in particular bringing the otherwise sterile bass to "life". Very dynamic. Very "alive" indeed.

 

[ghiberti]

congrats, man.

isn't there anybody compared green solo with 2007 solo + psu1?

I know Graham said they would be on par but I'm a little doubtful
about it cause green uses SMPS.

 

[Zorander]

Quote:

Originally Posted by ghiberti /img/forum/go_quote.gif congrats, man. isn't there anybody compared green solo with 2007 solo + psu1? I know Graham said they would be on par but I'm a little doubtful about it cause green uses SMPS.

Seeing that Graham is selling his own Solo amps (vs the PSU1, which he has to get off his company, a legal individual separate from himself), it's only reasonable to expect he will be pushing his amps more than he would the PSU1.

Yeah, it will be interesting to see a comparison of the new Solos with both PSU options.

 

[d-cee]

Quote:

Originally Posted by Zorander /img/forum/go_quote.gif Seeing that Graham is selling his own Solo amps (vs the PSU1, which he has to get off his company, a legal individual separate from himself), it's only reasonable to expect he will be pushing his amps more than he would the PSU1. Yeah, it will be interesting to see a comparison of the new Solos with both PSU options.

i think he's more doing this to beta test the new design, rather than to make some money on the side of his company, seeing as he owns the company

that and he or his company won't be allowed to sell the PSU1 after the new laws take effect

 

[Black Duck]

Quote:

Originally Posted by ghiberti /img/forum/go_quote.gif congrats, man. isn't there anybody compared green solo with 2007 solo + psu1? I know Graham said they would be on par but I'm a little doubtful about it cause green uses SMPS.

As I understand it, in addition to the RoHS compliance bit, the thing that makes the "green" the "green" is that it is specifically modified/adapted to use SMPS and tuned to remove crap that those, soon to be mandatory, blights on all audio, will otherwise freely inject into your audio signal.
The objective being to equal or surpass the performance of the current MC Solo.
In software release terms I see it as "RC final" out for evaluation in the wider community.
I expect the comparo you are looking for will be out and about in a couple of weeks when these units have had time to fully settle into their stride.
Early reports, as above, are extremely favorable.

 

[EFN]

Lovely and simple. If I gonna have a desktop setup I'd probably use the same setup

 

[wolfB]

Quote:

Originally Posted by mrarroyo /img/forum/go_quote.gif Next I chose Body and Soul by Billie Holiday. Not only do I continue to be amazed by the placement of the instruments but most importantly that sweetness and intonation in the voice of Billie Holiday comes right through.

Oh yes, I have an audiophile vinyl version of "Body and Soul" (MFSL 1-247]), of which I am pretty sure is in mono. I have to agree it sounds quite natural, especially from a fine speakers setup.

 

[mrarroyo]

Quote:

Originally Posted by d-cee /img/forum/go_quote.gif i think he's more doing this to beta test the new design, rather than to make some money on the side of his company, seeing as he owns the company that and he or his company won't be allowed to sell the PSU1 after the new laws take effect

Totally agree. BTW, Graham could make more money if we bought the Non-Green version of this amp. Just check the going prices.

I have absolutley no reason to doubt Mr. Slee, he says the Green Solo with its RoHS compliant construction and accompanying PSU sound better than the current Solo 2007 with the PSU1. Heck he will sell the PSU1 if you want it, but as I understood him you will be throwing your money away because the PSU1 will not make the Green Solo sound better.

 

[scompton]

Quote:

Originally Posted by mrarroyo /img/forum/go_quote.gif Well I rushed home (45 minutes to drive 34.6 miles in the middle of the Miami and Fort Lauderdale rush hour).

Miami traffic must not be too bad, or were you driving crazy to get to the new amp

 

[robm321]

Hurry up and listen ... more impressions

 

[mrarroyo]

Now for more Green Solo impressions! At about 20 hours I am feeding the Green Solo using my Arcam DiVA CD73 using a pair of RCA to RCA by Blue Jean Cables. The music I have selected is: Full House by Wes Montgomery (recorded 'live' at Tsubo - Berkely, California) and The Very Best of John Coltrane.

The cans have been the AKG K501 and today I started to use the Ultrasone PROline 2500 for the comparison. Instead of just listening to the Graham Slee by itself I decided to fire up my favorite amp, the Mapletree Ear + Purist HD100 to do a side by side. Please remember the Green Solo has only about 20 hours of burn in versus hundreds of hours on the Ear + Purist HD100 (maybe as many as 1,000 hours).

Three things I can easily tell from the side by side:

1. The bass on the Mapletree is deeper, however a true comparison will be done by yours truly in 3 weeks to see the evolution of the bass on the Green Solo. I will say that the bass the Green Solo has is deep, tight, and enjoyable. Most amps with so few hours would exhibit a bass that would be all over the place, un-defined and sloppy. Not so with the Solo.

2. The treble (highs) on the Green Solo extend further and it is easier to pick the subtleties of the instruments. In the Mapletree they are a bit rolled off, perhaps w/ better tubes and matched the sound would be much better. The Mapletree has the stock tubes except I swapped the Sovtek 5751 for a grey GE 5751

3. Soundstage is both wider but more concentrated on the Green Solo. This may sound like a contradiction so I will explain. On the Mapletree you hear a distinct left and right channels. When I switch to the Green Solo there are a left and right but also a middle. It is almost like the Green Solo has a "main amp" which reproduces what would normally be associated with the "center" an stereo music presentation while a "second amp" within the Green Solo handles the extreme left and right yet both are presented in the same plane and are easily herd playing at the same time. Or maybe the explanation is simpler and the Mapletree compresses the music and presents it mostly as a in the middle of the head.

Most of the above was with the AKG K501, which seem to have an special synergy with the Green Solo, versus the Ultrasone PROline 2500.

 

[Zorander]

Quote:

Originally Posted by mrarroyo /img/forum/go_quote.gif Totally agree. BTW, Graham could make more money if we bought the Non-Green version of this amp. Just check the going prices. I have absolutley no reason to doubt Mr. Slee, he says the Green Solo with its RoHS compliant construction and accompanying PSU sound better than the current Solo 2007 with the PSU1. Heck he will sell the PSU1 if you want it, but as I understood him you will be throwing your money away because the PSU1 will not make the Green Solo sound better.

I would lend you my PSU1 if only you lived closer (and use 220-240V input).

The proof is in hearing it yourself after all.

Cheers!