Altmann BYOB Amp & DAC

[consistent]

For your consideration...

Altmann Micro Machines BYOB Amp and Attraction DAC<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

I was looking for a second amp (new or used) that was reasonably priced as something I could tinker with. I have done up a few over the years and thought it would be fun to tackle again.

Trawling through the web I came across a few reviews that pointed to Mother of Tone-BYOB http://www.mother-of-tone.com. The reviews mainly spoke of a DAC that a certain <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Charles Altmann in Germany was producing, running off an ordinary car battery. I went to the site, did some further investigation, spoke to Charles Atlmann and ended up purchasing the BYOB Amp and his DAC. The Amp is EUR 750 (about $US 940 or $AUS 1250 landed) excluding any customs or other duties. The DAC starts at EUR 750 and can be built up to include Toslink, DVD sampling and a Jitter Scrambling Decorrelator (JISCO). And of course a 12V battery. Mr. Altmann recommends the Optima Red Top 34, new this will set you back about $US 125 or $AUS 315 (someone is making extra cash in Australia). By the way its tinker free so you cant tinker with it!

The following is an account of what I found with my purchase and is aimed at 2 channel purists.

BYOB AMP

The Amp arrived in a small box with the DAC. A picture and some reviews can be found at http://www.mother-of-tone.com/byob.htm so youll know what I am talking about. It took a few weeks from the initial order to arrival at my home, usual for down under deliveries of this size.

Yes it is small, very small! What have I done? I recognize a pot, a few capacitors, inputs/outputs and a heat sink but the rest is a bit of a mystery. Must be digital. People have been making 12V amps for cars for many years and I expect this little Amp to be similar in what it does, even with only 10 watts a side.

Plugged it in and turned it on, boy is it good straight out of the box. Quick and responsive with a solid bottom end. I also noticed that it had none of the Solid State Sound that many amps can deliver when mixed with the wrong gear. It had an easy listening, non-fatiguing sound but I noticed certain details were missing but it was quiet, dead quiet. I admit I am into detail, sometimes its an obsession over the music. I swapped between my current system and back to the Amp and concluded that imagery front to back and the top-end octave was not as good as what I am use too. I also noticed that you had to cook it for 30 to 40 minutes before it got better. The little heat sink does cook! I have speakers capable of producing 105db/w/m and I only needed to wind up the little pot no more than 25% of its full rotation, anymore and my ears would begin to bleed!

So back and forth I went over 3 weeks and during this time I began to hook up the DAC, swapping that back and forth. It was only in the last few days that I noticed the Amp come alive. Listening to my current system for a week or more then coming back to the Amp was an amazing journey. Probably took about 30 hours on and off but I found most of the detail that I thought was missing. As things progressed and the Amp cooked some more, I was also cooking. I couldnt believe the extra detail I was hearing and the bottom octaves became distinguishable, tighter, deeper and with pace. The top octave became clear and present although not as detailed as I am use to. I also thought background noise was less (yes even quieter than before) so I also got better front- to-back imagery. I found that I could increase the volume and there were no annoying noises or distortions that can make the music sound less than real. I was hearing music and nothing else. This Amp could match my amp in most areas and even surpass on aspects such as musicality and speed and it cost 1/3 of the price! The battery clearly adds another dimension and nothing like some of the battery amps I have auditioned and owned in the past such as N.E.W. I think because nothing is connected to the wall whilst playing you dont get the interference. Think what it can do for greenhouse emissions.

This little Amp is a performance standard as Charles Altmann puts it. I think it will give enough grunt to any speaker system 92db or above provided they are able to produce the transients without too much compression. The battery gives this Amp a shot of adrenalin whenever its needed which has the potential to allow a good speaker to become a really good speaker. Listen and you will hear changes in the energy fields, the singer as do instruments move toward and away from the mic, electronic music is lightening fast. For me piano and guitar sound thrilling.

Those audiophiles with massive phallic symbols of audio nirvana beware because David has found his slingshot! I have swapped almost 35 kilos for a few kilos, what a little wonder!

Strengths: What seems to be an effortless ability to let the music in providing huge capacitance for demanding works whilst still maintaining quiet when called for. Needless to say bass is landed with authority and depth and very distinguishable between lower octaves, piano, guitar and horns have life and voices have clear annunciation. Better (than most) instrument decay allows for greater appreciation of whats really happening in the recording. You dont need a pre-amp so there is less in the signal path, just right for the Khorns.

Weaknesses: Well it is ugly because its not in a box but I dont care. It requires a watt or 2 to make things happen and could have a better handle on the mini watts (maybe its because my speakers are too efficient) and the top end is a little shy on intricate detail.

BYOB ATTRACTION DAC

The DAC arrived in the same box as the Amp see http://www.mother-of-tone.com/attraction.htm for reviews and pictures. It too is small but does look like a DAC except smaller and without the pretty box. Depending on how you configure the DAC will determine how many toggle switches you have to play CD or DVD with any transport of your liking.

This also sounded great out of the box and the more I used it the better it became. The great test was to listen for a while (at least 15 hours on/off over 3 days) then go back to the sound you are used to. I did so and I did not want to go back, I ended up staying with the Attraction DAC and have not gone back since. My CD player is twice the price of the DAC; however I do use its transport.

This DAC was simply one of only 2 pieces of audio equipment I have heard play realistic music and raise goose bumps in 30 years of serious listening. The other is my Klipschorns. What a great combination I have made!

The DAC has the pleasantness and fullness of analogue, the sheer speed, timing and rhythm of a live performance and the detail digital brings. It produces lifelike music that I have not experienced before in a CD player or dac.

Its dead quiet and even quieter with its little buddy. As a combination they are hard to beat without spending a truckload more. The DAC picks up where most digital players leave off, it actual adds nothing to the recording but lets you listen to what was recorded. How can I say this? Because the music sounds like music and voices sound like voices. You do get a sense that you may actually be listening to what the engineer had intended DDD, AAD or ADD encoded. Its more like sitting in a club than in an auditorium 15 rows back from the stage. Its close and personal. Yes you do hear the nuances that are produced from orchestral works but spatial cues are different. It is somewhat forgiving.

Music and musicians come with an added dimension and as the volume is turned up the sound just gets better and the musicians are in the room with you. I dont sense much screaming that you often get with solid state when you wind it up, it has a tube presence but with lightening attack. It reminds me of the old Marantz CD 94 II and in fact I used one of these (transport) in my listening tests and found that this was a superb addition in enhancing the sound with the Jisco on. I have not been able to notice much difference with the Cyrus CD 8, using its transport and flicking the Jisco in and out of circuit.

Well there it is. An incredible piece of kit that you must audition! I found myself playing through a huge number of CDS listening to things I had not noticed before; this is always a good test for me. Combine with the AMP you just cannot go wrong!

Strengths: The scale of the sound is huge, rhythm, timing and overall tonality makes for lifelike presentation of artists. I feel as though the sound has become uncompressed and opens up in the room. It is free of the thinness or digital sounds often experienced with low Fi and even Hi Fi players. Its strength lies in its ability to present the first 9 octaves with full emotion. Affordability; just cannot think of anything that can compete with it at 5 times the price.

Weaknesses: Its not the prettiest thing you have ever seen. It is somewhat forgiving in the top end of its response losing some of the extreme detail that some players are capable of extracting but you pay for this.

Equipment used: Muse Onehundredsixty amp, Cyrus CD 8, DVD 8 and PSX-R, 6SN7 pre-amp (purpose built A Class), Marantz CD 94II, Morrison ELAD & Klipschorn (2004) loudspeakers. All cables and interconnects are home made.

Some of the CDS played: Diana Krall (Girl in Other Room), Dave Gruzin (Jazz compilation), Toto (Best Of), Santana (Supernatural), Eric Clapton (Unplugged), Buena Vista Social Club, Complete Beethoven Piano Sonatas (Gerard Willems), Verdi (Requiem), Mike Oldfield (Tubular Bells II), Mike Oldfield (Tubular Bells for Orchestra), Frank Sinatra (Best Of) and some Rammstein, Pink Floyd, Deep Purple and Emir Deodato.

Postscript: Charles Altmann says that the amp's sound may be 'tinkered' with

by playing around with the caps and adding/removing the black lacquer. By doing this you will get more/less emphasis on bass and treble but potentially lose some of the sweetness.

[Guest " "]

Very intresting and well organized write up.

I am in "DAC" hunting mode....looks like there's a lot out there.

[NOSValves]

Well written review! Have you sent this to various online Hi Fi mags? They may offer you a job. The only thing I was led to do was go research the amp you normally listen too as a baseline and I found almost nothing on it. So it may have been advantageous to give some more background on your baseline of comparison.

Craig

[mike stehr]

The BYOB amp may be the bees knees for all I know, but a 1000 bucks for a little printed circuit board with a few parts screwed down to a piece of spruce?

[kaiser SET say]

Sure seems like someone could pick one of these up and copy (not 100%) it and then turn around and sell them at a real world price because I'm with Mike on this little invention!

[consistent]

On a comparison note: I did have some mates come over with some cd's (one an avid tinkerer and builder) and all agreed it was well worth more than its purchase price and amazed at an ability to produce life like images. I think it throws people to see it sitting out in the open and inviting someone to copy it and put it in a bigger box. Comparing to my reference system I found that the detail in the top end of the Amp is not as 'present' as in the Muse, nevertheless it is still present. Charles Altmann says that can be easily fixed by taking the plastic off the remaining caps or changing out the caps. He builds to general tastes.The Muse amp is a big beast and still one of the best Amps I have ever had the pleasure to own but when I compare the overall delivery of the Altmann AMP/DAC combination my reference system is unable to compete, I think the DAC is the most impressive.

Yes it is not cheap for what you perceive you are getting but once you get over that you realize this is no ordinary combo. I took a gamble and let my ears do the judging and not the technology. I think Mr Altmann has priced it according to what it can deliver and where it can compete in the market.

Cheers

[playntheblues]

Thanks for sharing your thoughts with us, a very nicely writen review. I too would try this combo at a real world price. I understand that due to it's performance you may want to justify its cost. However if we had to buy everything that way a Corvette would cost $150,000.00, a pair of Klipschorns $50,000.00 and so on. If the item costs a couple of hundred dollars to build, double the cost and sell a ton of them. What do you guys think?

[consistent]

Thanks for your comments guys, it's a shame that while I'm typing your sleeping...or what ever else you do in bed!

[Parrot]

I enjoyed reading your review too.

[edwinr]

Thanks for that review. It was very interesting. I guess the up front asking price is fairly steep. But possibly proportionate to the thought and care that has gone into this design. I love the idea of a battery powered amp like that. If (when?) I get back into horns, this will be an option.