Pass B1

[Santy]

+1 for source selector

Sent from my GT-I9001 using Tapatalk 2

 

[sachu888]

Final list for r-core 18-0-18 or 22-0-22
1. APK
2. Santy
3. ruenigma
4. Hemantwagde
5. Denom
6. TheCoolestOne (2 Nos)
7. ngd
8. atharva
9. mbhangui
10. rohitmusic
11. satnai
12. Vikoma
13. Anilva

Final list for 5 - 1 source selector kit

Sann
Quad - 1 kit + PCB
keith_correa - 3 kit
captrajesh
apk
rohitmusic
TheCoolestOne
atharva
ruenigma
gobble
Santy
Omishra

Regards,
Sachin

 

[svaze]

Updating the list with my name.

Final list for r-core 18-0-18 or 22-0-22
1. APK
2. Santy
3. ruenigma
4. Hemantwagde
5. Denom
6. TheCoolestOne (2 Nos)
7. ngd
8. atharva
9. mbhangui
10. rohitmusic
11. satnai
12. Vikoma
13. Anilva
14. svaze

Final list for 5 - 1 source selector kit

Sann
Quad - 1 kit + PCB
keith_correa - 3 kit
captrajesh
apk
rohitmusic
TheCoolestOne
atharva
ruenigma
gobble
Santy
Omishra
svaze

 

[quad]

Sachin,

I found that I already have relays and other parts.

Please change mine to "4 Source Selector PCBs" instead of
"1kit+1PCB".

Also, this PCB has the relays driven by a transistor so that
this board can also be used with an Arduino or other controller, if so desired.

Refer to the links below - our circuit is nearly identical to this -

getting-started-with-arduino


Instructables Connecting-a-12V-Relay-to-Arduino

 

[keith_correa]

I need one r-core 22-0-22

 

[ngd]

Guys,

I have a few questions:

1. When are we expecting the parts to arrive?
2. When are we expecting the transformer? I have not paid anybody and from what I know it takes time. Am hoping that I have the transformer ready before we receive the parts.
3. What about cabinet? Is each guy for himself?

 

[srinisundar]

Anybody want cabinet can consider this too.Free shipping..1 Set Full Aluminum Power Amplifier Enclosure DAC Case Preamp Case PSU Box MH | eBay

 

[sachu888]

Guys,

I have a few questions:

1. When are we expecting the parts to arrive?
2. When are we expecting the transformer? I have not paid anybody and from what I know it takes time. Am hoping that I have the transformer ready before we receive the parts.
3. What about cabinet? Is each guy for himself?

Hi,
1. All parts should arrive in 1st week of Jan.I have received delivery of few parts including matched Toshiba Jfets.
2.I think Omishra has already ordered transformers for the group.I request him to post details regarding cost.You can also PM him.

Regards,
Sachin

 

[sachu888]

Anybody want cabinet can consider this too.Free shipping..1 Set Full Aluminum Power Amplifier Enclosure DAC Case Preamp Case PSU Box MH | eBay

Hi Srini,
The cab is very good,full Aluminium,but B1 Electrolyte caps are 50 MM in height,so internal height should be minimum 60mm else they won't fit straight.You can fit them like Audiodoc did here http://www.hifivision.com/diy/21036-pass-b1-57.html

Regards,
Sachin

 

[ngd]

I have PMed Omishra. Will post once I hear from him.

 

[ngd]

I received this from Om today:

Hi,
Yesterday, Atharva contacted me regarding his contact in Mumbai.so I hooded back my order with EMD, waiting to hear back from Atharva. You are local to Pune in that case you can collect from me if I get that. Otherwise Atharva will send/courier them to us.

Regards, Om

 

[ngd]

Re: Do we need a transformer at all?

This is my first DIY, so excuse the question if it is really dumb. I was reading the B1 document at PassDIY and it said:

The buffer uses an external power supply from 18 to 24 Volts DC. You can power it with batteries, but most convenient is an external regulated supply running off the wall. The preamp typically draws fewer that 0.02 Amps, so current is not much of an issue. A regulated supply is better, but the circuit is pretty good at ignoring noise on the supply and minor fluctuations.

If Nelson says that it is pretty good at ignoring noise, won't a simple DC adapter (brick or wall) be better? We are anyway going to have a wire running from mains to our box so we are not eliminating the wire but we will get good real estate where it matters: in our cabinets.

Any help will be appreciated.

-ngd

 

[atharva]

Yes I contacted Om yesterday. Initially I thought that 22-0-22 500mA will be sufficient as B1 manual states < 20mA. The price I got was 450+tax ~ 500/- + shipping. Om said that 1Amp will be required which they have quoted as 800 + tax ~ 940/- + shipping.

Since Om's estimate is 590~610/- I've told Om to go ahead.

 

[sachu888]

Re: Do we need a transformer at all?

This is my first DIY, so excuse the question if it is really dumb. I was reading the B1 document at PassDIY and it said:



If Nelson says that it is pretty good at ignoring noise, won't a simple DC adapter (brick or wall) be better? We are anyway going to have a wire running from mains to our box so we are not eliminating the wire but we will get good real estate where it matters: in our cabinets.

Any help will be appreciated.

-ngd

Hi,
B1 can be run on wallwart or batteries but a well filtered Regulated Power supply is always better.It will also help to power input selector board.It also gives you freedom to set different voltage.

Regards,
Sachin

 

[omishra]

Yes I contacted Om yesterday. Initially I thought that 22-0-22 500mA will be sufficient as B1 manual states < 20mA. The price I got was 450+tax ~ 500/- + shipping. Om said that 1Amp will be required which they have quoted as 800 + tax ~ 940/- + shipping.

Since Om's estimate is 590~610/- I've told Om to go ahead.

For 1 A rating this was my logic. Rather than B1 alone we add many devices into same chassis - phono stages, another buffer, LDR based volume control, source selector etc. So take steps now though not required immediately.

This difference is not that much. mere 25 Rs in case of EMD. Also transformers runs cool and silent below its 40% rated output. Also chances are we will pull more current from +ve rail mostly. This high rating will save transformer from noise. And not to forget this is for futureproof investment.

 

[TheCoolestOne]

The 1A rating makes more sense especially since most of us are / may end up adding phono stages, another buffer, LDR based volume control, source selector etc. Why not take care of that in this build stage itself.

 

[atharva]

For just 25/- Rs. more (from 500mA to 1A from EMD) totally worth it!

 

[ngd]

One more newbie question: why do we have a power supply unit? Why not use something like 7824 IC?

 

[omishra]

One more newbie question: why do we have a power supply unit? Why not use something like 7824 IC?

That 7824 is linear regulator IC which has more noise figure, LM317/337 based regulator has less noise. Also there are many features to this PS which takes it near to battery like dark background.

This is for your reference. This is vast thread, I am guiding to previous post.

 

[omishra]

Have you tried Toroidal before? Is it that much bad than R-Core?

Toroidal has good efficiency same like r core. But primary and secondary windings overlap each other. That acts like capacitance connected from primary to secondary which coupled high level of mains power noise into secondary side. Once ground is polluted it can not me removed completely and filters requirement gets costly. As we are handling tiny line level signal in Preamp which is more vulnerable to noise and could be amplified by power amps. So we need to keep cleanest possible PS. In case of phono stages signal level is max 2.5mV (0.0025V).