Updated: 04-Mar-02
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"Shame on me ? SACD; the new religion? New projects: ETAMSAS Loudspeakers & The 2 headed Dragon !! Again: Measuring Equipment..."

Shame on me ?

SACD; the new religion?

New projects: ETAMSAS Loudspeakers & The 2 headed Dragon !!

Again: Measuring Equipment...

Shame on me ?
Indeed, shame on me. I have not published in 2 months !! Still a wonder still people are coming to my Site. Yeah, yeah, I know the rules of good WEB Sites, make sure you update FREQUENTLY, well I didn't. Why? I was too busy with my hobby, hahaha! Bad excuse, but actually it is true. I am not a writer by profession, so I rather spend time, designing and constructing than writing......... yes, shame on me...... But in the meantime a lot of exciting things has happened and as you can see from the index above, it has not been 2 audio less months !! I have discovered SACD, a true great medium and in the meantime extended my hobby in the loudspeaker arena. Read all about it !! By the way, what happened with the DDDAC2002? Ahem, ahem, believe me, ALL parts are in house, I just have to start building. But the SACD adventure stopped me some how. I wanted to get acquainted with this new reference before I started to use my time here. But it will be for sure, certainly as this has become a bigger challenge now! Read below why.....


SACD; the new religion?
It started with audio friend Triodedick. He sent me a mail he bought a Sony SACD player, the "940". He was very enthusiastic, so I got quite curious. Good for me, the "940" is being dumped in Germany for 280 Euro. This is a ridiculous price for this stripped version of their old top model, so I decided to give it a try. I ordered at www.mediacheckpoint.de and  immediately a few SACD Disks at www.super-audio.de . A few days later the player was delivered and full of expectation I started the player. MMHHH, still a bit too fresh, too harsh, so I waited 24 hours with a disk on repeat... The next day I started my adventure with a Hybrid Disk. This means, you can play both CD (16bits/44.1kHz) and SACD from one Disk. The CD sound was not bad, but certainly not what I am used from the DDDAC. Never the less much better, than from the analogue output from the Marantz CD10. I am sure this has to do with the superb DAC and use of much better OPAMPS (OPA 2132) than the Marantz (NE5534, pfffff). So actually I was pleasantly surprised that still with OPAMPS a reasonable good result was possible ! I switched to digital out connected to the DDDAC, so I could compare the 2 as CD Drive. To be honest? very little difference. Too small to bother. the CD10 has a little more rest in the soundstage. But it is really small. So again, I was a happy man. Than the moment of truth..... I switched back to analog output and used the SACD layer. Set my self in the listening chair and concentrated on listening. HUHHHHH ????? I HATE superlatives, but I was with **** mouth !! I admit, I was. I hate this really, because too oft this is used for small audible improvements, but this is worth it. How does it sound? Well, the same music and tonal balance, but with a real acoustic ambiance. I only experienced this with my LINN combination and the best Vinyl. But on top of that, unbelievable power, very dynamic, ink-black background and the best BASS I ever heard (Glad I recently built the Master SUB, hahaha!) No comments? Yes, after a few days, I realized that the analog stage was not free from typical OPAMP effects. Although I must admit that I am still impressed. The pin point was not always 100% and the highs are a bit sandy, corny. But what the heck! This is a 280 EURO player !!

What happened next? Again Triodedick emailed me that he was writing a article for an Audio magazine on the Sony "777". The flag ship from Sony. I checked the Internet and could not find anything else, than jaw dropping articles. To make a longs story short, I went out and bought me one (2.900 EURO in Germany), which I consider (now) as a bargain. For the noble Brands you pay 5 times this price..... Again Long Story short: This Player has been burning in for 3 weeks now (he needs it !!!!) and is the best I ever heard on digital medium, BOTH CD and SACD. all on analogue out. I am smacked that the analog stage is so good. I must say, it is designed wonderfully, Sony must have employed Audio lovers to design this beauty. Also the new DAC Chip from PCM1738 DAC from Burr Brown is used. 3 in parallel  for each Channel (in stereo, I do not have 5 Tube amps speakers (yet?) for 5.1 multichannel). I strongly believe that the implementation of a ANALOGUE FIR Filter in this DAC is the secret to its superb sound. Both SACD and CD are "transferred" into a bit stream signal (what is quit easy for the SACD, hehehe...). This signal is than chunked In a 6 bit analog FIR filter and the rest in a normal digital filter en MASH DAC part. Now the current output can be followed by a simple filer. This gives you best of both worlds! Great idea from Burr Brown and well implemented by Sony. The rest is also well designed; separate power supply, local regulators, use of audiophile components, an XO Clock, great PCB layout, etc etc. The Drive is  solid as a TANK. How does it sound? On CD out it is comparable with the DDDAC. And that is a extra drive to try to make the DDDAC2002 better (I will use the PCM 1738 there as well, you can count on that) On digital out, the SONY Drive beats the CD10 Drive somewhat, which is a compliment for the very rigid drive design. More control, tighter Bass. Wow..... On SACD??? Incredible. Go find out your self. This is really GREAT. I am lost. I am converted to this new believe..... SACD is the future ! I have seen the light ! Ok, down on my feet now, what's next? very simple, tweaking the "777" ofcourse !! I already I have Sowter Transformers to pick up the current outputs from the DAC's and see if by passing the (I repeat: very good) analogue stage makes it better !!! If this is done, I will share this ofcourse with you........ In the meantime I spend al my pocket money buying SACD Disks (Amazon also has a wide choice !!) and enjoy the great musical performance this format is bringing to my living room, day after day.........


New projects: ETAMSAS Loudspeakers
The first of 2 new projects, I have started is another loudspeaker system. Why? I asked my self as well. I have spent last year good money on the HGP speaker system which is introduced on this Site as well. Is it bad, definitively NO ! Actually it is very good. But, well, you know, may be, could it, would it, ..... Real DIY people always like to design and built something from their own. One year ago, I had no inspiration which loudspeaker chassis to use. Till recently, where I made such good experience with the Master SUB. The unit used here is a ETON Chassis with the famous HEXACONE design. I figured that a midrange speaker must sound very nice as well with cone material like this. The 4 inch chassis looks very suitable for that purpose. Remember, I do not need frequencies below 150Hz. That portion of the HGP is active any way. Than I read about their new tweeter, the ER-4, an air motion transformer. A zig zagged foil, 10 times the size of a dome tweeter, but same mass, which attracts and distracts as signal is applied and more or less explodes the air out of the wrinkles. This should result in a very transparent and dynamic sound. Further more, low resonance at 600 Hz. Thanks to the way the tweeter is constructed; no voicecoil, but conductive layers on the foil, it reacts as a real resistor from aprox 4 Ohm. Simple filtering possible....  Sounds promising, eh? Ofcourse I use the HGP as a reference, so I decided (logically) to exactly copy the enclosure of the HGP satellites for easy positioning in the existing stands. By the way, I like the design any way. To make this a real hobby I bought Hobby Box 4.0 and a measurement microphone. I do want to gain experience with REAL speaker design. Not just build something, change a little bit around the filter components and than say, MMMHHH this is nice... I am half way constructing now, so check the Other Projects. 


New projects: The 2 headed Dragon !!
The second little project is the "2-HEADED DRAGON" What the heck should that mean than ??? Some time ago I "silver" wired my loudspeakers in BI-Wiring mode. When connecting the silver wire to the LS Poles at the amplifier, I realized there is a lot of wire at the secondary winding in the output transformer. So, the filigran currents for the tweeter were still "pushed under" by the brutal currents of the low mid range.....  Haha, I know the answer, BI-Amping ! Well, very expensive I must say. So my first thought was to have at least 2 Output transformers. Some experiments were done, but not successfully. Till I spoke with Will Blaauw who delivered the amorphe transformers on getting new coils with secondary silver windings. Suddenly I realized, that if you put a BI-filair winding at the secondary, the solution was there !! So..... next month I will have an output transformer with 2 secondary windings. One in Copper and one in Silver. Why the 2 different materials? very simple, 5 possible combinations to experiment and really COMPARE what the influence is on the sound reproduction. MMMHHH I am really looking forward to this experiment !!!!  To be continued, so to speak !!!


Again: Measuring Equipment...
From my previous columns the reader knows, that I am an absolutely forfighter of using T&M equipment during the design and evaluation phase. Having decided to built a loudspeaker system, I realized I have nothing to actually measure the acoustic response, impedance curve, waterfall diagram etc etc. What to do? I thought this was only affordable for Speaker manufacturers ??? I started searching and found a great package at http://www.audio-software.de/ so called Hobby Box 4.0 together with DIY (even better, hahaha) measurement microphone. The microphone is not perfectly linear, but it comes with a dB-Frequency correction file, to be used with Hobby BOX. So the effect is extremely linear. If you buy a linear mike like this, they get nasty expensive.... It goes too far to describe this whole package in detail, but if you have a look at all the graphs at the project page, you will see what I mean. This is great stuff. This really will help me to design a speaker system with a professional support. My ears will do the rest, but I want to be able to find correlation's between listening and measuring. This will help to find new ways and that combination, you might have overlooked with the Trial and Error methodology, so oft used by us, the DIY. 


Happy Listening and Building !!!!

Doede Douma


IMPORTANT: The information provided on this page is intended as guide for DIY activities and therefore free to copy and or publish. If any one wishes to use any of the information from my WEB site, please make sure to refer and footnote to my URL Link as source! Doede Douma