Pass B1

[sachu888]

I have few inquires for full set of B1(B1+LDR+Power supply)

1.Capt. Rajesh
2.Bhaskarcan (2 kits)

I will order PCBs and parts if five or more members are ready to take part.

Regards,
Sachin

 

[sachu888]

Hi,
Members interested for B1(full kit):

1. CaptRajesh
2. Bhaskar(2kits)
3. mbhangui

It will take min on month to receive all parts.Everyone needs to buy R-core trafo and all other hardware like RCA,Toggle,case etc.

Regards,
Sachin

 

[mbhangui]

Hi,
Members interested for B1(full kit):

1. CaptRajesh
2. Bhaskar(2kits)
3. mbhangui

It will take min on month to receive all parts.Everyone needs to buy R-core trafo and all other hardware like RCA,Toggle,case etc.

Regards,
Sachin

Sachin,
Thanks. One slight modification. I need 2 nos of LDR kit instead of 1.

 

[doors666]

i will take an ldr with parts and a psu board.

 

[captrajesh]

Hi,
Members interested for B1(full kit):

1. CaptRajesh
2. Bhaskar(2kits)
3. mbhangui

Sachin, since I've already made a B1 which has a power supply and procuring the second B1 to sandwich the LDR between the two B1s, I would be needing only the B1 PCB and components in place of the SSP that I had ordered earlier.

 

[sachu888]

Ok,modified list for B1 GB

1. CaptRajesh(Only B1)
2. Doors (One LDR kit+PSU board)
3. Bhaskar (2 Full B1 kit)
4. Manvendra (Full B1 kit and extra LDR kit)

I will wait for 2 more days than close this GB.

Regards,
Sachin

 

[gobble]

I vaguely recall there were some upgrade improvements found for this kit? Why don't you make the upgrade part of the standard parts list for the new GB?


Just a suggestion. And correct me if my recollection is only my imagination.
--G0bble

 

[sachu888]

I vaguely recall there were some upgrade improvements found for this kit? Why don't you make the upgrade part of the standard parts list for the new GB?


Just a suggestion. And correct me if my recollection is only my imagination.
--G0bble

Hi Gobble,
Only upgrade is adding an active pre like Simple active preamp makes the sound better.Everything else is same.Members may upgrade PRP/Nude Vishay(Foil) resisters and expensive cap of their choice later.

Regards,
Sachin

 

[gobble]

Hi Gobble,
Only upgrade is adding an active pre like Simple active preamp makes the sound better.Everything else is same.Members may upgrade PRP/Nude Vishay(Foil) resisters and expensive cap of their choice later.

Regards,
Sachin

Duh! So we upgrade one pre by adding another pre in the chain? Enlighten me please?!!

PS: I like the Nude suggestion - does listening to music naked improve the enjoyment of sound?

--G0bble

 

[sachu888]

Duh! So we upgrade one pre by adding another pre in the chain? Enlighten me please?!!

PS: I like the Nude suggestion - does listening to music naked improve the enjoyment of sound?

--G0bble

Thinking of making boards of LDR resister replacer New "Kit" on the Bolck - BrianGT /LM3886 Upgrade - Page 3 - diyAudio reviews suggested it sounds better than those expensive resisters.

Regards,
Sachin

 

[omishra]

Duh! So we upgrade one pre by adding another pre in the chain? Enlighten me please?!!

Please read my post #832 from http://www.hifivision.com/diy/21036-pass-b1-84.html

It was issue with source loading causing drop of LF because of LSA impedance of 13K? exposed to source. To hide the LSA behind buffer I added SSP. This sounded excellent. But SSP is having unity gain which was not my requirement, I wanted no (zero) gain, pure buffer. Hence I replaced SSP with another bulky B1 (shared PS with first B1).

Now it looked like: Source -> (B1->[LSA->B1])->Power amplifier
in above statement, PS is not shown but present there and
() - inside preamplifier
[] - second B1

This made input impedance of B1 exposed to source (1M?) and first B1 drives to LSA. Second B1 shows output impedance of 50?, drives power amplifier. Same configuration was successful and sonically nearby >95% equivalent when both the B1 replaced with SSP, but there is 2X gain added by 2 SSP.
e.g. Source -> (SSP->[LSA->SSP])->Power amplifier

This make it buffer both the ends, make any source in the world happy by means of very high input impedance. All power amps are drivable with very low output impedance and LSA in control of volume level.

This made no loss of frequency response and adequate driving of source and power amp made life easy with net result cleanest possible I listened in my setup.
Regards,

PS: I like the Nude suggestion - does listening to music naked improve the enjoyment of sound?
--G0bble

Depends upon what do you listen, when and where?

 

[gobble]

Please read my post #832 from http://www.hifivision.com/diy/21036-pass-b1-84.html

It was issue with source loading causing drop of LF because of LSA impedance of 13K? exposed to source.

Thanks! Exactly what I was parroting to Linuxguru and anyone else I spoke to about the LSA more than a year back.

--G0bble

 

[doors666]

Other workarounds:
Use source with low output impedance. ten times is considered acceptable. if your soure's output impedance is less than 1300 ohms, then you should be able to use source to lsa. Most of the modern sources do better than this. Which source had this lf dropout issue?

Whats the output impedance of lsa? people run lsa as a standalone preamp also. if your amp's input impedance is very high, we should be able to use the lsa after the b1. so the source faces the preamp and the lsa handles the amp. Follow the atleast ten times rule.

 

[sachu888]

Final list of members:
It will take min 30 days to receive all parts.

1. CaptRajesh(Only B1)
2. Doors (One LDR kit+PSU board)
3. Bhaskar (2 Full B1 kit)
4. Mbhangai (Full B1 kit and extra LDR kit)
5. Vin_eme(LDR kit)
6. nraghunadh (Full B1 kit)

Regards,
Sachin

 

[sachu888]

Final list of members:
It will take min 30 days to receive all parts.

1. CaptRajesh(Only B1)
2. Doors (One LDR kit+PSU board)
3. Bhaskar (2 Full B1 kit)
4. Mbhangai (Full B1 kit and extra LDR kit)
5. Vin_eme(LDR kit)
6. nraghunadh (Full B1 kit)

Hi all,
PCBs have been ordered.Please find approx cost
Full B1 kit(LDR+Power supply+B1) = Rs 4500
LDR kit = Rs 900
Power supply kit = Rs 800
Only B1 kit = Rs 2800
Shipping would be Rs 100 wih DTDC.I will need min 50% amount in advance.Please PM me if you don't have my bank details.

Regards,
Sachin

 

[bijinmb]

I came across a web site which has kinda good quality Pass B1.
Hope this might be useful for all the FM.

Some of the highlights i found good is below:

1. Matched( matched to 100uA or less !) low noise Toshiba J-FETs;

2. non-polar low loss MKP 1uF capacitors for coupling purpose.

3. Wima MKS 4 capacitor ;

4. Dale metal film resistors;

5. 10K dual gang volume pot ;

6. 2mm thick and 75um copper thick PCB ;

7. LED and diode .

Price is also affordable i think, around 2500 INR including shipping from hong kong.

Anybody have any idea about this version of Pass B1?? Please share your thoughts...

This store is a trusted store, because myself and few other friends of me have experience buying from them before. Very swift and prompt reply and shipping so far...

But i am curious to know about this version of Pass B1. Please let me know if anybody have purchased that Pass B1 from jims_audio store...

Class A matched SE J-FET stereo buffer kit ! | eBay

 

[captrajesh]

I came across a web site which has kinda good quality Pass B1.

Price is also affordable i think, around 2500 INR including shipping from hong kong.

Anybody have any idea about this version of Pass B1?? Please share your thoughts...

Class A matched SE J-FET stereo buffer kit ! | eBay

AFAIK, all Nelson Pass DIY circuits are not for commercial use. If someone is doing it, he is violating the copyright of the author. If he has made significant mods not to come under the ambit of copyright act, the SQ would have also changed significantly and most likely to worse.

Moreover, @Rs. 56 per USD this works out to 2050/- plus shipping plus customs plus uncertainty about receipt of the parcel. I would stick to our forum's group buy price which is 2800/- for the B1 kit.

 

[sachu888]

I came across a web site which has kinda good quality Pass B1.
Hope this might be useful for all the FM.

Some of the highlights i found good is below:

1. Matched( matched to 100uA or less !) low noise Toshiba J-FETs;

2. non-polar low loss MKP 1uF capacitors for coupling purpose.

3. Wima MKS 4 capacitor ;

4. Dale metal film resistors;

5. 10K dual gang volume pot ;

6. 2mm thick and 75um copper thick PCB ;

7. LED and diode .

Price is also affordable i think, around 2500 INR including shipping from hong kong.

Anybody have any idea about this version of Pass B1?? Please share your thoughts...

Class A matched SE J-FET stereo buffer kit ! | eBay

Jims Audio has got good praise all over.I always avoid buying from China even though this particular seller has a good reputation.We have used better parts with original PCB design in B1.It costs only Rs 300 less than our B1,but you never know custom charges.He is providing Wima Polyster caps which are not good for audio.We have AXON True Capacitors metalized polypropylene(better than Polyster and even some high end PP caps).
Edit : We can't match cost with Chinese vendors,as they always order parts in bulk.They can always provide better price.

Regards,
Sachin

 

[omishra]

I came across a web site which has kinda good quality Pass B1.
Hope this might be useful for all the FM.

Some of the highlights i found good is below:

1. Matched( matched to 100uA or less !) low noise Toshiba J-FETs;

2. non-polar low loss MKP 1uF capacitors for coupling purpose.

3. Wima MKS 4 capacitor ;

4. Dale metal film resistors;

5. 10K dual gang volume pot ;

6. 2mm thick and 75um copper thick PCB ;

7. LED and diode .

Price is also affordable i think, around 2500 INR including shipping from hong kong.

Anybody have any idea about this version of Pass B1?? Please share your thoughts...

This store is a trusted store, because myself and few other friends of me have experience buying from them before. Very swift and prompt reply and shipping so far...

But i am curious to know about this version of Pass B1. Please let me know if anybody have purchased that Pass B1 from jims_audio store...

Class A matched SE J-FET stereo buffer kit ! | eBay

I have bought PCB from him, those were supposed to be 2mm but actually are 1.6mm. That prompted me to design my own. Again caps are the earning points they are looking al-cheapo, its body melts while soldering. (I recently bought similar kit). No power caps into that, you have to buy it. (Add another 300 + tax + shipping for it). So its your bargain.

At last I have more faith in Nelson pass provided/designed machine files than anyone in the world.

 

[bijinmb]

I don't think that is a fake design. and its SQ is a matter of actual evaluation rather than a wild guess. And you know many such legendary designs are available in the market though its copy protected with law!! sad but true and that is a fact as well...

Anyway i just gave an information that is all. I will be building myself in the near future..and i have procured all its components...but just for personal use...