Salas hotrodded DCB1 resistor tryouts

[AndrewT]

I know they will introduce a little something soundwise,

how did you prove this to yourself?

 

[Scorpion]

how did you prove this to yourself?

AndrewT,

By trying/comparing troughout the years crimped vs non-crimped (bare wires) speaker jumpers, interconnects and speaker cables...

That is how I ''proove'' it to myself... Other audiophiles from Montreal were here to compare as well. Maybe some of them (members of DIYaudio) could jump in ?

Sadly, I don't have a catalog of datas that could be examine by the scientific community to accept or discard (after all the mathematical graphs have been analyzed) what I (we) heard....

Differences ? VERY VERY subtles loss of transparency and, instruments/voices becoming very slightly bigger (compare to prior sizes without sleeves). We are talking tiny subtleties but, noticeable nontheless.

Regards

Scorpion

 

[Scorpion]

Ok, here are the first pics...I KNOW THE 470R ARE NOT IN THE SIGNAL...MY MISTAKE...but since they were bought...

 

[Scorpion]

And...

 

[Scorpion]

Ok so back after 2 weeks vacations...

Here are some more pics.

 

[Scorpion]

And some pics of the ''Test Board'' with the copper pigtails...some components still not installed (not received).

Sorry if the pics are not very good. I really s*** at taking pictures.

Regards

Scorpion

 

[Salas]

Stocking up I see. You will write the "Scorpion BOM with notes" in the end of your experiments I presume. So any aspiring "Deluxe DCB1" builder could use it as a subjective compass.

 

[BigE]

What?! No Vishay nudes?

 

[Scorpion]

What?! No Vishay nudes?

Hi BigE

Yep...see pics above. I have Vishays Naked Z-Foil Tx-2575 at the 220R position.

Going to compare them to Shinkoh Tantalums (among others).

Regards

Marc-André

 

[BigE]

Sorry, I missed them. Carry on! I'm very interested in the results of your testing.

 

[Scorpion]

Stocking up I see. You will write the "Scorpion BOM with notes" in the end of your experiments I presume. So any aspiring "Deluxe DCB1" builder could use it as a subjective compass.

Hi Salas

Well, I'd say...experimenting more than stocking up ;-)

I will start testing very soon. Still waiting for some components.

Btw, I am having a very hard time choosing between different stepped attenuators (also vs pots). I was told I needed between 10k-20k. I guess, you already figured by now that I don't want to skip on quality but I still can't decide wich one would be best between these (soundwise AND price/quality ratio)...

I would like to go dual-mono.

Here are a few stepped atts I had my eyes on:

- Shallco 45 positions, shorting, dual-mono L-pad (@ Michael Percy)
- TKD 40 positions, mono stepped attenuator (@ Michael Percy)
- Seiden 34 or 46 positions, shorting, 2-pole, rotary switch (@ Parts Connexion)

Please feel free to send advice. Any other suggestions are welcome.

Thanks a lot

Regards

Scorpion

P.S. As far as a ''Deluxe BOM'', you guies are going to be able to follow the whole process of my experiences and interveine. That being said, if a BOM is desired by the DCB1 builders here at DIY, I will make one.

 

[BigE]

You wouldn't happen to own an A/D convertor would you? Then you could record and compare each change in real time....perhaps even make wav files available?

 

[Scorpion]

You wouldn't happen to own an A/D convertor would you? Then you could record and compare each change in real time....perhaps even make wav files available?

BigE

I do have a seperate DAC (to go along with my drive). It is an Audiomat Maestro 2.

Do you think it will cut it? If so, what would be the best way to do it? I kept your suggestion about the ''Audio Difference Maker'' stuff.

Regards

Scorpion

 

[BigE]

Not DAC, ADC.

 

[Scorpion]

Off topic but should any of you be interested. Lots of Black Gates/Mundorfs/Dynamicaps for sale:

http://www.diyaudio.com/forums/swap-meet/254027-black-gates-mundorf-dynamicap.html#post3878131

Thanks

Regards
Scorpion

 

[gadut]

Wow, amazing effort that you've done which remind me of my past journey. after completing my_refC, I also had the same spirit to build 'my style DCB1 parts', but after reading whole audio chain project, I decided to directly choose audiograde parts instead of trying 1by1 as you do. I can't imagine the permutation of each parts on my diy audio chain if it's done with your approach:

audio source (not sure yet) -> DAC AD1865+tube pre -> DCB1 -> AlephJ

maybe most difficult effort for me, build chassis and good layout which also consume trial and error, where my dcb1 chassis is still not final yet until now.

my parts selection attached, not as massive as yours. and if someday you are bored with those Z-foil+BG N, just let me know

can't wait to read your listening results

 

[Scorpion]

Wow, amazing effort that you've done which remind me of my past journey. after completing my_refC, I also had the same spirit to build 'my style DCB1 parts', but after reading whole audio chain project, I decided to directly choose audiograde parts instead of trying 1by1 as you do. I can't imagine the permutation of each parts on my diy audio chain if it's done with your approach:

audio source (not sure yet) -> DAC AD1865+tube pre -> DCB1 -> AlephJ

maybe most difficult effort for me, build chassis and good layout which also consume trial and error, where my dcb1 chassis is still not final yet until now.

my parts selection attached, not as massive as yours. and if someday you are bored with those Z-foil+BG N, just let me know

can't wait to read your listening results

Hi Gadut,

Thanks for the comments. You chose excellent components all around. How do you like the sound of your DCB1 ? How would you describe it?

We are going to have some differences though at the very end. I too went with a TKD stepped attenuator but I decided on 2 mono stepped atts @10k from Michael Percy. It is a bit of a gamble but I have read a lot on steps in the last days and the TKD comes frequently as one of the most musical and natural sounding on the market (even compared to Shallco 45 steps att.). According to reads, this musicality comes at the price of a slight loss of ultimate details....Personnaly, I am more than willing to trade extra details (wich I already have plenty enough) for musicality. Music first. Don't want to end up being distracted by too much details.

Of course, reading is one thing and listening is another. So my ears will be the final judges as to wheter the TKD is as good as reported. Seiden seemed excellent too, but, going 2 monos + resistors would set me back close to 1 Grand...too much $$ for me.

Other differences is that I will have 2 TX (100 Va X 2) and seperate PSU. And I will go with 2 ohms@12 watts Mills for CCS resistors so this thing will run very hot !!! This is for the " test board" as I have Mills MRA-12 1,25 ohms for my final board !!

I ordered huge custom heatsinks from HeatsinkUSA in order to be able to deal with the heat. Heat will be further dissipated through the aluminum enclosure (5/16" thick all around).

Btw, guies do you think I would need extra heatsinks for the MUR860 (or IXYS Hexfred or CREE Schottky) if I am to use 2ohms (or 1,25ohms).

Better be safe than sorry.

Thanks

Regards
Scorpion

 

[BigE]

Yes, I would sink the diodes at that level.

I am a bit surprised that you're not including the CCS resistor in the tests. Anecdotal reports say that Caddock (with clip on heat sinking) is best at that position.

 

[Scorpion]

Yes, I would sink the diodes at that level.

I am a bit surprised that you're not including the CCS resistor in the tests. Anecdotal reports say that Caddock (with clip on heat sinking) is best at that position.

BigE,

That's what I thought (about sinking the diodes) but was not sure it was needed.

As for the CCS resistors, didn't think it would make a difference. Could give the Caddocks + heatsink a try if reports by members indicated an audible difference between CCSs. I am curious.

Btw, BigE, Salas and others, I read here and there that increasing current (lowering CCS resistor value, to 2 ohms in my case) gives a "bigger sound"....please specify what was meant by "bigger" as for me too big a sound is NOT something I like.

I like singers, Instruments and soundstage to have realistic and believable sizes. I can't stand a singer as big as a wall if you know what I mean. Sounds false to me.

In other words or to put it simply, what are the audible improvements by increasing current ?

Thanks for your inputs.

Regards
Scorpion

 

[gadut]

@Scorpion,

I get stereo tkd att just because local price is the same as mpercy mono, also have tkd carbon and alps blackbeauty to compare someday. But until now I don't have time to complete the chassis, my twin babyboy have my weeked I'm happy enough to watch the light show, simetrical V+ / V- and <2mV dc offset

I'm using 3 paralel 10R dlaloric, I tried 5 paralel but dlaloric can't stand the heat eventhough it's spesification is 7W. I have 5mm alum plate sized 30x38cm with 2 heatsink 8x8.6x20cm, It's just getting warm after hours of running. I also put small heatsink on each mur820, can't feel any heat from them.

My suggestion is complete your build first and to stay focus with your main purpose as Resistor try out, for other parts just pick up any choice. You can mix & match them later