Three days with the Solo

Oh yes, I am now a proud owner of a brand new Solo with PSU1... delivered to me with incredible speed and efficiency on Tuesday afternoon!

I won't express my complete impressions on the amp yet: I still have to listen to many CDs with it, and I prefer to have at least 10 more days before a final judgement.

But one thing I can already say... I am an engineer, with a slight knowledge of electronics (I am an automation/computer science engineer after all), and I have always been a big sceptical when it comes to matters of audiophile nature.

Burn-in of purely electronic components? Ok, but only to test premature mortality... not certainly because performance can change in time, can't it?

Do the cables matter? Well, a decent cable is of course required (good shielding and insulation, good firm contacts, correct impedance and no unwanted parasite capacity, good section and purity of the conductor) so it might be wise to spend a bit more than the bargain brands. But surely the 1000 Eur cables can't be better than the 50-80 Eur ones, it becomes a matter of "placebo effect", of "snake oil".

And, come on, these audiophiles spending so much money in esoteric equipment and saying they can hear the difference between a well encoded 320 Kbps MP3 and the original CD...

So, I have always been very sceptical (and I still am on many matters), but I have always loved well made unpretentious technical equipment. Stuff without fluff, sturdily made, which sounds good. Not the crappy commercial equipment, but neither stuff with pretentious names and brochures made by snobs for snobs.

Why buying a very fine headphone amp like the Solo? Well, several reasons... One is the humility, the lack of "bullsh*t" in Mr. Slee's words, his will to talk of the technical details without bathing them into mystique (on the other hand, always very practical and solidly down to earth). I have been reading reviews and forum posts for months, and the more I read, the more I kept the name "Solo" in my mind as a "must buy in future". All reviews were in praise, and I am not talking of review from magazines with a big revenue from advertisement. And the amp itself looked simple, almost spartan. Like I said, stuff sturdly made with one and only purpose: lasting in time (I hope!) and sounding good, with no compromises in quality or bragging about things one can't humanly deliver. Add to this the charm of an item which is hand-made and tested, and I was ready to give it a try.

I have always listened to music, either on a Philips compact stereo at my parents', or in my car stereo, or at the computer with crappy Philips/Sony headphones (the 15 Eur ones with creaky sound). I still remember in 1996, when I still was a university student and I went to buy a new pair of headphones to replace my broken ones. The guy in the store offered me a pair of Sennheisers which costed 4-5 times more than what I had in mind... not to mention that I had never heard of Sennheiser (I thought it was a no-name off-brand!), and I walked away. Years later I learnt that it was a reputable brand...

Nothing changed until October 2007, when I broke another pair of crappy 15 Eur headphones and decided to give a try to the Sennheiser HD-595. Holy cow! Even straight from my sound card output, they sounded so great! I had never heard such sounds before from a headpone!

And the rest is history... A Denon 1930 CD/DVD/SACD player, then an old integrated amp recycled from an old stereo system I had at my parents'. Another step in quality: the sound from this amp was so much fuller and dynamic than the sound card's output. Sure, it was very warm and "thick" sounding (very "coloured") but after getting used to it (and some reduction of the bass with the pot on the amp) it was good.

And now, in the last two weeks, a nice USB DAC (the SuperPro 707) and the Solo.

So, on Tuesday afternoon I was looking for great things... and some great things came. The Solo showed transient responses so fast that I was in awe, an unprecedented clarity and detail, a stereo separation which was so good I could point a finger at the instruments. And yet, it was damn bright. The highs were a bit shrill, and there was very little bass. Sure, the vocals were rendered marvellously, and Nick Cave's voice was soooo clean. It was very "transparent" and neutral, except for those slightly dissonant high frequencies. But then the words about burning in came to my mind... and I decided to wait.

In the meanwhile, I played some Metallica (very good, except for the lack of bass), some Opeth (fantastic: the clarity and speed of the Solo brought out some details that had always been buried beneath the buzzing distorted guitars), some Depeche Mode (again, the lack of bass was sorely felt), some Mark Knopfler ("Shangri-La" on SACD has never sounded so good, with crystal clear guitar picking), and various other test tracks.

But it's only today, after 72 hours of being on (and 6-8 of them playing music), that the amp really started to come to life. It was immediately evident that something had changed from yesterday, the sound was already thicker (but NOT bloated, or woollen, or greasy). So I decided to blast my ears with some Prodigy (The Fat of The Land) with the volume knob on 12 o'clock position. I know it's too much... but it was just a test.

Here is the content of the e-mail which I sent to Graham today:

I decided to give the Solo a go with The Prodigy: their landmark album "The fat of the land" is one of the most severe tests for heavy and hard hitting bass I can imagine... and it rocks!

I can definitely feel that bass response has already improved a lot, and my HD-595 doesn't distort/clip a bit even if the sound pressure is louder than I had ever previously gone with my previous amp (the volume pot is almost at 12 o'clock position) on this recording.

I still think that my previous Pioneer amp had a fatter/warmer colouring which at times could be pleasant with bass-heavy music (although more often the hard beats sounded wrapped in a bucket of molasses, and I had to turn the bass frequencies down a notch with the equalizer), but as sheer bass impact, precision, brutality and tight control of the dynamics the Solo is miles ahead. Really, this album truly sounds mean and vicious on the Solo... Powerful and hard like a block of granite, but still clean and not bloated. Now I understand what is meant with "studio reference": the amp must not colour the music (even if it's a pleasant colouring) at the expense of precision, speed and detail. You should add in your product instructions that if one comes from lower-spec equipment, not only the amp has to burn in... the listener must change his "hearing" philosophy a bit.

Yes, I have never heard this CD with such a raw power, such an energetic delivery. Bass was there, finally! Very dry (which IMHO is much more enjoyable than the sloppy and fat bass of cheap boomboxes), but plentiful.

And, incredibly, with my previous amp this same CD on the HD-595 clipped and distorted like hell (at an inferior volume than today). So it wasn't the HD-595 which was uncapable of controlling bass, it was my previous amp which was uncapable of driving them correctly! This is a proof that it's not the POWER of an amp that matters (the Pioneer was VERY powerful), it's the quality of what it outputs! The same consideration applies to other CDs I have tried tonight: with the Pioneer I had to stop with the volume knob because the bass response went out of control, with the Solo I have to stop not to hurt my hearing... because it won't distort. It will be loud, but still precise and not in difficulty in driving the headphones. From now on I don't want to hear that an HD-595 is a low impedance phone and so it can be easily driven by ANY headphone output (like many reviews say), because it's bullsh*t... A good amp matters, and quite a lot. And the famous Sennheiser "veil"? I can find no veil at all with the Solo...

So, I am definitely happy with the purchase! I will keep posting my impressions as long as burning in continues (and yes, I believe in burn in now: thank you Mr. Slee!)...

PS I also got rid of all ground loop isolators in my equipment. Now I have the Denon player and the DAC connected to the Solo with Van Den Huul cables (the basic ones, not the expensive kind), and I can detect NO hum at all even with the volume pot in the maximum position. From the DAC (on input 1 of the solo) I could hear a very slight high frequency "hiss" at maximum volume on the first day, but today I can't hear it at all anymore. And I haven't even connected the ground post on the back of the Solo (no tingling feeling on the aluminum case, so no need for that)! For comparison, the Pioneer amp hummed and hissed unless isolators were placed on its input connections: again, a proof that a quality electrical design DOES matter!

Congratulations on your new toy! Let the Solo SRG burn in, it will astound you with when it reaches 400-500 hours plus of burn in. I use a tuner feeding music into the Solo SRG 24/7. Good luck and enjoy it.

Edited by mrarroyo - 07 Feb 2009 at 12:43am

Back in 2005 when I eventually managed to obtain a full compliment of RoHS compliant components for each of our products (these are components with all the Lead and a number of other alleged hazardous chemicals removed - as required to be able to sell electronic equipment in Europe these days) and after building each product using them, I felt like shutting the business there and then, why?

The sound wasn't just bright! It shrieked! It hurt the ears!

Burn-in made it worse!

My ears have a memory of the days everything sounded right - my mission after accepting these people are empowered to do all these nasty things on us was to try and live with it.

Anyway, to continue, my mission will never be complete because not one single component manufacturer since RoHS has put in the same 100% they did before then. EU legislation has destroyed the will of many people.

It is very well disguised because admission of failure is a taboo in business for obvious reasons. I have never admitted to failure, instead I have put myself through the hell of making it work - this is not boastfull and please don't read it that way.

But consider this, my ear's memories drive this manufacturer, but I know being part of the industry that many others worried at that time - yes, those "too big to fall". How do I know this? Ever heard of a breed of people called "representatives"? They call on you to sell you their wares. They can sometimes let slip who else they sell to...

For anyone wanting to research this, one has to look just who stopped selling in Europe during 2005-2006 - just who now is prominent in some places but not in Europe. Or maybe they still use the old components and hope they are never found out (it is possible!).

The problem for me is not my equipment but the equipment used to drive my equipment. Old gear is generally OK and will deliver the requisite signal. But what of the RoHS compliant gear? And like the GM field adjacent the Organic field, some RoHS compliant components get in the equipment made and sold outside Europe.

Nobody is going to tell you about their RoHS problems (I've found) apart from me. Therefore nobody ever really knows what they really have with stuff made since 2005-2006.

The Solo is designed and measured to be "flat". It can be made to sound hyper-bright and still measure "flat" - how can this be? If I had the complete answer to this (instead of just most of it) I would be the richest manufacturer on the planet - and if I kept it under my hat, possibly the only manufacturer on the planet!

Therefore, when partnering the Solo with a particular source, the above is worth bearing in mind.


Edited by Graham Slee - 08 Feb 2009 at 6:18am

Little update... I have always found rather hard to detect the difference between MP3s encoded at 192 Kbps VBR or 320Kbps CBR. Sometimes I got it, sometimes not.

Today I made a little experiment with various tracks, of course blind (thanks to my wife's assistance). With the Solo, the difference was immediately evident... like night and day. The decay on guitar was a particularly tell-tale sign. It's the first time that I hear the difference so well...

Another way of saying how much the Solo is transparent and revealing of details.


Edited by Lucabeer - 08 Feb 2009 at 11:43am