[dnewcomer]

I would like to get 4 transformers also, let me know when its time.

thanks

[jhm731]

Hi Everyone,

Anybody are interested in purchasing of SC947-02 would like to know this. First, I am not related to anybody at Scientific Conversion and not working or get any contributes from Jon Paul but I am here to share how good is the SC947-02 in my SB3 right now. I am enjoying my music very much after installing SC947-02 and now planning to install another one into my DAC tonight (as the way JoshK is introducing about Jon Paul's research). If I can do it you can do it too since I am only a DIY amateur for awhile. This kind of mod is easier and cheaper than you spend hundreds for such thing that you keep spending more and more. Either I or F100 will post a short review after we have done the job. You will be amazed with SC947-02's modifications. Good luck to all.

Since the SB3 isn't grounded, where did you connect the SC947-02's shields to?

[tanchiro58]

Jhm731,

If you try to open up your SB3 and follow the coaxial digital output you will read GN, which is the same line with negative to digital connector. That is the SB3 ground that I connected the shielded pin of the SC947-02 to. Well at least my modded SB3 works pretty good. Good luck.

[JoshK]

Like I stated earlier, I'm in for 2 trannies. Any update on the group buy? How many more to go?

The ongoing tally is on page 2.  11 more to go and we will hit the critical 50 mark.

[GBB]

should work for any dac.  basically you should see the input of the sp/dif terminated with a 75 ohm resistor to ground and that should be replaced with the transformer. 

Josh,
The way you phrased it makes it sounds as if you are saying one replaces the 75 ohm resistor with the transformer.  If that's not what you meant, then forgive the following correction.

When you add an input transformer to your DAC, you still need to have the 75 ohm termination.  It should be wired as follows:



The input capacitor isn't needed if you are using transformer coupling from the SB3 or if you are sure your transport isn't putting out an DC that could saturate the core of the transformer.

---Gary

[GBB]

Thanks Gary (GBB) for providing us this mod!!!

You are very welcome.  Thanks to you and Tanchiro for keeping interest in this mod alive.

---Gary

[GBB]

11 more to go and we will hit the critical 50 mark.

Josh,
Put me down for a couple.  I might bump it to 4 down the road if you need a few more to put you over the top.

---Gary

[tanchiro58]

should work for any dac.  basically you should see the input of the sp/dif terminated with a 75 ohm resistor to ground and that should be replaced with the transformer. 

Josh,
The way you phrased it makes it sounds as if you are saying one replaces the 75 ohm resistor with the transformer.  If that's not what you meant, then forgive the following correction.

When you add an input transformer to your DAC, you still need to have the 75 ohm termination.  It should be wired as follows:



The input capacitor isn't needed if you are using transformer coupling from the SB3 or if you are sure your transport isn't putting out an DC that could saturate the core of the transformer.

---Gary

You are the MAN, Gary. I took out the resistor 75Ohm at my DAC to replace the SC947-02. There was NO SIGNAL at all. Then I had to solder it back in and there you go I got my music back. It sounds cleaner and more musical and articulate for a moment. I will let it brake in for awhile then tell everybody how this mod is going to be superb. Thanks a lot.

[jhm731]

Jhm731,

If you try to open up your SB3 and follow the coaxial digital output you will read GN, which is the same line with negative to digital connector. That is the SB3 ground that I connected the shielded pin of the SC947-02 to. Well at least my modded SB3 works pretty good. Good luck.

If you use the GN on the board, you're connecting the shields to a ground plane loaded with SMPS/RF/EMI noise.

I suggest you try connecting the  sc947-02 shield connections(there are two) to a separate clean external ground.

PS- I'm the one who suggested to GaryB to try the  SC947-02.

[tanchiro58]

Jhm731,

If you try to open up your SB3 and follow the coaxial digital output you will read GN, which is the same line with negative to digital connector. That is the SB3 ground that I connected the shielded pin of the SC947-02 to. Well at least my modded SB3 works pretty good. Good luck.

If you use the GN on the board, you're connecting the shields to a ground plane loaded with SMPS/RF/EMI noise.

I suggest you try connecting the  sc947-02 shield connections(there are two) to a separate clean external ground.

PS- I'm the one who suggested to GaryB to try the  SC947-02.

I agree with you at this point and have discussed with F100 where is the real ground unless we build another enclosure for the SB3 with an external ground, is that right?  :oops:Thanks.

Regards,
Tan

[JoshK]

gary,

yes you are completely right.  I don't know what I was thinking when I said that.     reflected load and all... thanks for the correction.

[poseidonsvoice]

Josh,

Count me in for one as well. I need to get this SB3 mod done! You know how to reach me 

Anand.

[GBB]

If you use the GN on the board, you're connecting the shields to a ground plane loaded with SMPS/RF/EMI noise.

I suggest you try connecting the  sc947-02 shield connections(there are two) to a separate clean external ground.

PS- I'm the one who suggested to GaryB to try the  SC947-02.

JHM - thanks for pointing out the SC947-02.  If you need a pat on the back - here it is.  But to be honest, I don't expect any significant difference between it and the 916-01 that I used before.  Both are shielded.  The main difference is that the SC947-02 is designed for use up to 192Khz sample rates while the 916-01 is only designed for 48khz sampling rates.  But the SB3 only supports up to 48khz sampling rates so that doesn't matter.

So why am I buying a few SC947-02 now?  Tan told me that Scientific Conversions no longer sells the 916-01 so I figured I'd pick up a couple of the new ones and do a little experiment.

Regarding the question of where to ground the shield - I respectively disagree.  Ground is not some magical place that sinks all bad things, sort of like a black hole for electronic noise.  Ground is just a reference point that we chose.  For the shield, we want to have a low impedance ground at high frequencies so that any high frequency noise that tries to couple from the transformer primary to the secondary is instead shunted to ground.  If your shield is grounded a few feet away from the SB3, I guarantee you that it won't be a low impedance ground.  You'd be better off not hooking up the shield at all.


---Gary

[sts9fan]

I would like to grab one of these also.

Thanks

Kris

[JoshK]

Well, Jon Paul said that technically their min purchase quantity is 25.  ...
 He said if we get up to an order of 50 that the price drops to $11.50 each. 

Here is the list I have of those who said they wanted in:
Krikor - 2
jrebman - 3
MarkM - 4
2wo - 2
rotcoddam - 2
Builder Brad - 4
JoshK - 4
CornellAlum - 2
mgalusha - 2
brian t - 4
hanguy - 4
crooner - 2
gordy - 2
dnewcomer - 4
GBB - 2
sts9fan - 2
F-100 - 6
rajacat - 2
poseidonvoice - 1
posternutbag2000 - 1
---------------
total = 55

Guys, above is the updated order list as of now.  If anyone sees that I left someone out, got the number desired incorrect or changed their mind let me know.   The total has been creeping up slowly each day and we are now 8 away from hitting the critical discount mark which makes it worthwhile for us all.  I am sure that SC is happy for this as well instead of dozens of small orders. 

I should probably leave the order open till Friday evening to give time for everyone to see it.  I will then look to place the order on Friday.  If we are a few shy of the 50 mark by Friday (which I don't expect), then I will pick up the extras as there is always late comers that wished they had gotten in on the GB. 

The way this will work is scout's honor.  If you tell me you want X number of the transformers, I will order that many for you.  I will pay for the order, place the order and when the units arrive I will start collecting money and shipping the tx's.  This way if there is any delays for whatever reason, you haven't given me any money till I am ready to ship to you.  I think this avoids the usual problems with GB's on other forums.  I have done this once on another forum for a small GB and it worked out well. 

[F-100]

Josh,
  Please put me down for 6 units. Thanks

[sts9fan]

you can put me down for 2 then.

[tanchiro58]

If you use the GN on the board, you're connecting the shields to a ground plane loaded with SMPS/RF/EMI noise.

I suggest you try connecting the  sc947-02 shield connections(there are two) to a separate clean external ground.

PS- I'm the one who suggested to GaryB to try the  SC947-02.

JHM - thanks for pointing out the SC947-02.  If you need a pat on the back - here it is.  But to be honest, I don't expect any significant difference between it and the 916-01 that I used before.  Both are shielded.  The main difference is that the SC947-02 is designed for use up to 192Khz sample rates while the 916-01 is only designed for 48khz sampling rates.  But the SB3 only supports up to 48khz sampling rates so that doesn't matter.

So why am I buying a few SC947-02 now?  Tan told me that Scientific Conversions no longer sells the 916-01 so I figured I'd pick up a couple of the new ones and do a little experiment.

Regarding the question of where to ground the shield - I respectively disagree.  Ground is not some magical place that sinks all bad things, sort of like a black hole for electronic noise.  Ground is just a reference point that we chose.  For the shield, we want to have a low impedance ground at high frequencies so that any high frequency noise that tries to couple from the transformer primary to the secondary is instead shunted to ground.  If your shield is grounded a few feet away from the SB3, I guarantee you that it won't be a low impedance ground.  You'd be better off not hooking up the shield at all.


---Gary

I am thinking this idea of SB3 modification is to SHARE to AC members who wants to improve their hi-end systems by not spending or waisting their money for some of expensive audio components or to let them be modded without satisfaction except people who care more about brand name hi-end stuffs.

Thanks to Gary(GBB) had guided me throughout the process of modding. Gary is true about the SC947-02 since I had asked Jon Paul about the old version (SC916-01) and he suggested to get SC947-02. F100 and I took the risk and effort to experiment with the new transformer version. And now we have succeed and would like to share to everyone here.

[Builder Brad]

Hi Josh,

please increase my order to 4 x transformers.

Brad

[poseidonsvoice]

Josh,

You forgot to stick me on the list! Put me down for one. Thanks,
Anand.