Salas hotrodded blue DCB1 build

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pinnocchio

pinnocchio

Member
Joined 2010
quebecdiy.forumactif.com/
Nice!!!

I'd love to come listen to your setup eventually.

Ciao!
Do

Scorpion said:
Well, 99% done...at last !!!!
(Will design the aluminum "volume gradation" ring to go around the knobs a little later)

I would like to take the opportunity to say a HUGE thank you to Salas, TeaBag, AndrewT (even if we sometimes had different points of vu, I respect what you bring to DIY community) and others who shared tips and all along the way.

You guys helped me more than I would have hoped.

My DCB1 has the test board in and is now playing. Really impressive, very well balanced sound even if music has been playing for about an hour only. Tonaly, it is almost scary good...

Can't wait for the "burning" to work its magic...

Anyway, thanks a lot again and again. Now moving to "DCB1 resistors tryouts" thread as I will begin testing soon (starting resistors kit: 220R Shinkoh tantalums, 1M Riken Ohms, 220K Allen-Bradley @ less than 5% after drift).


Here are a few pics.

Regards
Scorpion
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Salas

Salas

diyAudio Chief Moderator
Joined 2002
Paid Member
Audiomat does that stuff with the out of PCB large lytics and MKP cans bypasses too. So you built in "Audiomatic" style a DCB1 to match. Looks aesthetically coherent in the system photo indeed. The speakers are interesting. A Eurocentric system. Should be rendering good timbre.
 
S

Scorpion

Member
Joined 2002
pinnocchio said:
Nice!!!

I'd love to come listen to your setup eventually.

Ciao!
Do
Click to expand...

Yep, you are more than welcome Pinocchio to come to my place and have a listen. DIY Audio member Praudio (who I think you know) will also come as well as 2 other audiophile friends (one of them is a musician).

If you are interested in listening to "resistor tryouts", you are also welcome.

Since we are from Montreal, it should be pretty easy to get in touch. I also would be very interested to listen to your balanced DCB1.

Just PM me if you want to have my coordonates.

Regards
Scorpion
 
nezbleu

nezbleu

Member
Joined 2009
Scorpion that is absolutely amazing casework! I'm not sure I would have made exactly the same choices even if I had the talent, skill, and money to build something to that level, but I respect the choices you made and the quality of execution. Really impressive stuff!

Are those white LED's I see? That is one area I would have some doubts, as red and yellow LED's have less noise as a rule. Still, that's pretty minor, and the physical build quality will offset a lot (not much noise is getting into that chassis!). I am envious.
 
S

Scorpion

Member
Joined 2002
nezbleu said:
Scorpion that is absolutely amazing casework! I'm not sure I would have made exactly the same choices even if I had the talent, skill, and money to build something to that level, but I respect the choices you made and the quality of execution. Really impressive stuff!

Are those white LED's I see? That is one area I would have some doubts, as red and yellow LED's have less noise as a rule. Still, that's pretty minor, and the physical build quality will offset a lot (not much noise is getting into that chassis!). I am envious.
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Hi Nezbleu,

Nope, the LEDs are amber. I already knew about noise issues with different colors. If memory serves me well, I think amber is the quietest, than green than ?? I was told reds were more noisy...!!!

Btw, thanks for the comments. Nezbleu, you are also more than welcome to come have a listen anytime (as Pinocchio and Praudio). As DCB1 owners, we could take the opportunity to share tips and all.

Even after only about 24 hours of continuous music (burning) playing, I am stunned at how balanced and musical it sounds from the get go.

Again all the props to Salas. This guy is such an asset to DIY community, I just don't have the words.

Regards
Scorpion
 
nezbleu

nezbleu

Member
Joined 2009
Scorpion said:
Yep, Vdrop across the CCS resistors. 1,38 for the positive side and 1,19 for the negative.
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That's a very good match. 10R CCS resistors? So about 138mA pos and 119mA neg, let's call it a 20mA difference, that is nothing. Since you have the hypnotize board and the BFPS (Big Effing Power Supply) you will probably want to drive at least double that current at some point.

It's the voltage across the 100R near the LEDs quintet and the 0,22uF caps on the HYPNOTIZE board. 1,03V on the positive side and 0,98V on the negative.
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OK, so that represents the current the FET pulls through the LED's, about 10mA in each case. Not a particularly meaningful measurement.

Ok. Don't know wheter I could hear a difference since I need to pop the board in first...wich I haven't done because of the "you know what".

Still, is this kind of DC Offset difference acceptable (like electrically speaking, for example)? If there are no real issues related to the DC Offset difference, I am even considering letting it "as is". After all, this board is the "test board" for the "resistors tryouts". That is his main purpose.
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Depends on your power amp. If the power amp is all DC-coupled then >3mV may (or may not) be an issue. Let's assume a power amp voltage gain of 26dB, which is not unusual, then 3mV offset at the input of the power amp would be about 60mV at the output, which isn't going to heat your voice coils too much. OTOH, if the power amp is AC-coupled none of this really matters, and the 3mV offset is not enough to push the DCB1 into asymetrical clipping. I wouldn't worry about it(although, actually, like you, I would probably obsess about it for a bit, and I would consider swapping those FETs in that channel; in fact an ideal offset would be 0 or less than zero, slightly negative).

BUT: the proof of the audio pudding is in the listening, so that's what you need to do! :)
 
nezbleu

nezbleu

Member
Joined 2009
Scorpion said:
Nezbleu, you are also more than welcome to come have a listen anytime (as Pinocchio and Praudio). As DCB1 owners, we could take the opportunity to share tips and all.
Click to expand...

Thanks for the invitation, but it's a long drive from Halifax to Montreal (about 1200Km?), so I doubt it will be this weekend! :D

Still, I do get up there once in a while, it's one of my favourite cities, and for sure I will reach out to you if I am heading that way. Perhaps next Jazz Festival, or even Nuit Blanche!

(My last trip there was about a year ago, we flew up to hear KT Tunstall at Gesu on Bleury.)
 
S

Scorpion

Member
Joined 2002
Salas said:
Audiomat does that stuff with the out of PCB large lytics and MKP cans bypasses too. So you built in "Audiomatic" style a DCB1 to match. Looks aesthetically coherent in the system photo indeed. The speakers are interesting. A Eurocentric system. Should be rendering good timbre.
Click to expand...

Yep, having visual synergy with my Audiomat gears was the main goal as far as designing the enclosure. But, my DCB1 is much more sturdy. It weights at least 75-80 lbs. I will probably weight it just out of curiosity.

As far as having large lytics out of PCB, Audiomat distributor once explained me in technical details the advantages of doing it this way. You know how NOT technical I am by now but it was something along geting more musicality (with something along current drawing and very low ESR). I don't know, I couldn't explain it.

What I do know is how Audiomat gears have outstanding musicality when properly matched. I call it magic pure and simple. Very very hard to find. In fact, only when one finds it can one understand what it is. Great matching can often ensure great sound but getting magic and the "soul" of music is a totally different story.

Anyway, back to big lytics, I don't know. I decided to take a similar route as Audiomat and wheter this path is the right one or not is a ? for me but if I judge from how musical this DCB1 sounds, I would be inclined to think it might have at least a little something to do.

But again, what do I know. ..only how impressed I am.

Regards
Scorpion
 
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S

Scorpion

Member
Joined 2002
nezbleu said:
Thanks for the invitation, but it's a long drive from Halifax to Montreal (about 1200Km?), so I doubt it will be this weekend! :D

Still, I do get up there once in a while, it's one of my favourite cities, and for sure I will reach out to you if I am heading that way. Perhaps next Jazz Festival....



Oops sorry, I should have checked first. I saw a Canadian flag and a french nickname (Nezbleu) so I assumed you were from the area.

Montreal Jazz Festival is real interesting so should you be in the area, you'll be a welcomed guess.

Regards
Scorpion
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nezbleu

nezbleu

Member
Joined 2009
Yeah, haven't been to the Festival du Jazz de Montreal in a couple of years, but it really is the best jazz festival in the world (I think Down Beat rated it #1 years ago, ahead of Montreaux etc.). I love the volume of free music venues there. I recall one amazing night watching/listening to a blues performance featuring some French (from France, not Quebec) harmonica player, and as the evening went along the fireworks festival/competition on Ile Ste. Helene started, so fireworks displays hung in the air above the stage. Later we rocked to a wondeful band from Togo (which featured a dancer we nicknamed "the Gogo from Togo"), and the next night Wynton Marsalis and friends performed a tribute to Louis Armstrong on the outdoor stage at Place des Arts. Absolutely magical. Of course, all this was fueled by Cinquante and debrizener sausage :)

Oh: Here in Nova Scotia we are called "Bluenosers", so for my "nom de screen" I chose "Nezbleu". No Acadian roots that I know of, just liked the name.
 
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Salas

Salas

diyAudio Chief Moderator
Joined 2002
Paid Member
@ Scorpion

In the context of your high investment in mechanical build and numerous boutique parts evaluations I propose you get a desoldering gun too. It will help you making your modifications clean, fast, and safe. 1.6mm extra nozzle tip for thicker leads would come handy too.

An externally hosted image should be here but it was not working when we last tested it.
 
S

Scorpion

Member
Joined 2002
Thanks for the info Salas. Will definitely look into it.

Oh, and BTW, the resistors swapping will not need soldering/desoldering as they will be removable in a "plug and play" kind of thing as I already installed copper sleeves at the very end of copper pigtails (which are solder to the PCB).

It can be seen on one of the pics if you zoom in.

In any case, a good desoldering tool sure comes handy.

Regards
Scorpion
 
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