Mar 172010
 

THE ECOFAN SOUND 6A3 SINGLE ENDED VALVE AMPLIFIER AND
MATCHING PRE-AMPLIFIER



Those moments in life where one has a complete audio revelation are sadly rare but over the last year I have had such an experience from some kit that was left in for me to hear by one of my customers. Now one thing when working in the audio trade (I no longer do) that most live in fear of, is the customer who says he has found or designed gear. The problem comes when you have to tell him/rarely her, that their precious is not very good, or even dangerous. This happened to me early this year when a customer, now a friend, told me about some amps he had found in New Zealand. The story goes that he was walking down the street, and heard a fabulous sound coming out of a record shop. After a conversation with the shop keeper, he had found out all about a repair guy, who as a side-line, designs and hand builds his own valve based audio products.  My friend went to the workshop, and a relationship both with him and his designs was born. He calls his audio products Ecofan Sound and he and his company are based in Auckland. Murray Dick, makes a small range of products, all valve, and ranging from low power, single ended to high power push pull stereo and mono block power amplifiers. There is also a matching line stage pre-amp (reviewed here) and a larger more complex pre with built in phono stage. Ecofan has also recently introduced new products in the form of a Tube buffer and a Boost it. I have heard the Tube Buffer, but as it is new and not run in, I will not comment on it at this stage.

The items I am reviewing, are the 5 Watt 6A3 valve power amplifier, and the active two input, 6SN7,6N7 pre-amplifier . The power amp is class A and does run quite hot. It is very compact ( 10 x 8 x 6 inch’s tall (Transformers) and ways a ton for its size ( if you ever wondered what a crushed car might weigh, this is a good indicator). Fit and finish are good but very plain and there is a retro feel to things. If you want bling look elsewhere.

The two input, two output  pre- amplifier uses 6SN7 and 6N7 valves, with the valves mounted on the outside of the very compact case ( 4.5 w X 3.5 h X 8 d inch’s) .  The switches are very retro flick types, and the action in use is very solid. The volume control is very smooth and easy to set, with gain over the whole range not just the first quarter; everything is manual, no remotes here. All mains leads are fixed, so it would seem that Murray does not believe in after market power cords. I did not see the packaging or instructions and during the times I have used these products I have had no issues. All worked flawlessly every time used. Internal construction is hard wired, parts quality is good, and is neat but cramped due to the compact nature of the designs.

The 6A3 is a double plate triode with a 6.3 volt filament, pictures of these at (]www.tubeworld.com/6a3.htm] ). During the course of this review I also tried a number of 6A3 valves. These included Vt 52 by Western Electric. 6A3’s by Rca, Tung-Sol, Cunningham and Raytheon. The best sound in my system was achieved with the Raytheon, with the Cunningham’s next in quality. The others just sounded thin or overly warm and lacked the gain of the Raytheon 6A3’s. These valves are similar to the 6b4G but are a 4 pin design to the 8 pins of the 6B4G and thus can’t be substituted. It may be in your system/application that one of these other valve makes may sound better so feel free to try.

The System used for the review was as follows…..

A Marantz CD 7 ( on a Project wall shelf with a Clear light Audio Isolation board, Mains lead was a TCI Boa Constrictor.) Ref 3A Dulcete Speakers on Attacama R 724 stands with 4 inch granite slabs supported via Michell Tender Feet. The Amps sat on a Mana Reference frame and Base 02 isolation platform. Speaker cable was XLO Type 6 and interconnects Audience Au 24 rca-rca 1m. There were no mains filters or regenerators used during the review, and the room is 7 foot deep x 8 and a half foot high x11 foot long.

Music used.

Rickie Lee Jones – The Magazine.  Track 4 It must be love.

Nitin Sawhney – Beyond Skin. Track 1 Broken skin, track 2 Letting go and track 5 Tides.

The Dali Demo disc. Track 3 by Hugh Masekala The coal train.

Murray Dick is a no BS kind of guy, and while I have never met him, he reminds me of Roger A Modjeski of Music Reference in the United States (www.ramlabs-musicreference.com/), he also is a no BS kind of guy. I have a Music Reference Rm 200 amp which is a 100 watt KT66 valve amp with a solid state input, fabulous sound. Having read Roger’s site and communicated with him via e-mail I feel he and Murray are cut from very similar cloth, but have their own unique views as well. Roger is another rare thing in audio a no compromise designer who values the end user more than many others. Read about him on his site, its a good read. Murray believes in no positive or negative feedback and no caps in the signal path (direct coupled), except for the bypassed bypass ones on the power tubes cathodes. He also believes in maintaining correct phase through out. He states that not to do this “Decreases the thereness of the sound ” Ecofan make their own transformers in house and I believe Murray winds them himself. The transformer are very large for the physical size of the amps and much of what they do is down to these quality output and power transformers.

The Amps were allowed to warm up for about an hour before listening began, but sounded very good after about 30 mins. Being a class A design, the power amp runs very hot, and good ventilation must be given to it.

I could give you a blow by blow account of how each track sounds but I don’t feel its absolutely necessary, so I will give you the salient points. These Amps posses a clarity and purity I have never heard before. I know that single ended does this and I have heard many such amps before. However I have never experienced this degree of purity. When lent these amps before my friend asked what I thought. I responded by telling him that ” He had ruined me “. For a few thousand pounds these out performed all my other amplification, much of it well regarded (most of it up to 5 times the price ). Bass was deep and extended and a very wide screen sound stage hung between the speakers. They disappeared leaving just the music and wow what sweet music. I was constantly amazed at how the sound was so effortless, responding to each change with total ease (and this with speakers that while suiting the room perhaps are not the best choice for these amps. What would bigger more sensitive ones sound like ?). Constantly I was blown away by how well percussion was reproduced. Cymbals had air and shimmer and very real decay, even multi layered tracks still allowed space for this type of decay. This Pre-power combination managed to make every type of music sound both beautiful, delicate and yet powerful the degree of frequency coherence was like nothing else I have ever heard (so far ).

The Hugh Masekela track a South African Song of sorrow ,Stimela ( The Coal train ) has everything bar the kitchen sink in it. Guitar, keyboards, Sax, Trumpet, percussion and drums and the very soulful voice of the lead singer ? On the liner notes for the cd and I quote ” The band groves like there is no tomorrow and the laid back performance forces the listener to ask;How can anything so laid back and yet so tight at the same time ?” This is one of the best live recordings I have. It was like being there. every part of the performance hung in space. The fabulous musicianship both moving and breathtaking. The swings in dynamics tracked with ease, never once did the sound waver. When the ten minutes had passed I just wanted to immerse myself once again in this music. It was sumptuous.

If there was any negative compared to the experience I achieve in my other system, it was a slight lack of weight and scale. However as I have already hinted a bigger room and more sensitive speakers would give that extra bit more. In the small room I was using for this review, I don’t see how the sound could have been any better.

One other concern raises itself, and that is the temperature this amplifier reaches during normal use, and with more than adequate ventilation. After a few hours of use, the metal work is very hot.  Now Class A amplifiers of any type are usually hot to the touch, after and during use. By its very nature Class A amplification is wasteful of energy, and that waste energy is expressed as heat and lots of it, this is the reason why many of these designs use massive heatsinks to remove this waste heat from the amplifier’s case. The 6A3 amplifier design uses the case alone to serve this function, and as it is quite small, I feel long term, that the internal components may be exposed to more heat than they might like.  I would suggest that Murray  should either increase the size of the case work, or add a heat sink (if possible) in order to guarantee component longevity. Its a small, but vital point, in my opinion and will lead to a better overall design.

I consider myself to be very blessed to have heard this set up, and as Murray refuses to play the normal audio game (direct selling, bespoke construction, and no distributor margins to pump the price up) only a very few will have had that pleasure.  No magazine would review this kit, simply because of the craftsman nature of Murray’s business model, i.e small production runs and mostly made to order only. I wanted to share this Ecofan Sound with you, because I feel Murray is one of those rare exceptions in audio life, a true gifted genius, who refuses to compromise on his vision. Pure commercialism at worst destroys this, and at best,  forces to many compromises which rob designs, such as those from Ecofan Sound of their true potential.

I award, in my upstairs system, a score of 9 out of 10 for the sound quality these  New Zealand valve based products  helped create. Now I don’t know if a 10 exists, in the context of this small room system,  but this is as close as I have got  so far, in this room to a 10.

Some time in the future, I want to hear this pre-power combination, on the end of bigger, more sensitive speakers, in order that I can experience the full weight, scale, purity and clarity this matching will give. The risk in doing that is the potential increase in valve noise. In the context of my second system, the Raytheon valves gave the best sound, despite higher noise than some of the other types tried. In the context of my Ref 3A speakers this was acceptable, but with larger horn types I fear this might not be the case. Of course some of those other valves tried might yield better sound in the context of your system, and a number of them had much lower noise levels, than the Raytheon power tubes I was using. So some tube rolling may be in order to squeeze a bit more out of the 6A3 amplifier speaker match.

I feel this pair of valve designs from down-under are worth a punt, especially at such a low cost, even with the joke the pound had become recently. This is at the end of the day the most amazing factor in this review, the very low cost for so much sound….. WOW ! Your right Murray, it is like being there, and your entry level kit has got me more there than anything else I have tried so far in that system, and room….Thank You Murray.

Neil

Source of Review Products Loan….. End user owner

Thanks go to Francis for the review product loan, and also Adam from Ecofan Sound for technical information.

Ecofan Sound’s website is http://www.ecofansound.com/

NB. Copyright ownership of some images used in this review do not belong with me. If there is a problem contact me please.

© Copyright 2010 Adventures in High Fidelity Audio.

NB No part or portion of this article may be reproduced or quoted without written permission.

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