Pass B1

[Santy]

I meant we dont have to short them do we?

I guess in the earlier builds they were used fr the DPDT switches.

No shams, not to short them (L2/R2). Only if we are using the switching option on B1 board, we would connect them to the DPDT switches. In our case, we need only one connection, always on, so we will short only the L1/ R1 points to the middle.

My confusion is how to connect the rotary switch to the input selector, this post from sachin has a drawing but the image wouldn't load :sad:

 

[omishra]

Oops.. atlast i thought to have an shootout of Music hall 25.2 integrated player Pre-out against Pass B1 pre... How it performed.. Not to disappoint ...$600 Music hall 25.2 won.. However for the Price and the music output nothing in this price factor can beat the B1

-------------------------------------------------------------

That's interesting, I guess the B1 was sold @ $1000,
so I'll look at a 600$ preamp beating a 1000$ :-D

Here is another quote from NP himself.

Assuming that it is working correctly, the B1 is very neutral. It's not even really a preamp - it's a buffered volume control. There are plenty of people
who aren't looking for that, and it's no problem by me if they prefer something
else.

 

[TheCoolestOne]

My confusion is how to connect the rotary switch to the input selector, this post from sachin has a drawing but the image wouldn't load :sad:

Yes I too couldnt manage to open some images. Maybe Sachin / Om can repost the required pics once they can loacate them.

Pictures of how to connect the volume pot, source selector pot and how to connect the different boards to each other and to the R core would help. Though some connections are fairly straight forward it pics would help us reconfirm out own connections

Ealier posts have loads of pics and have helped immensely but some important pictures would not load.

 

[Santy]

Connecting POT to B1, om has explained already

About pins -
Hold shaft towards you and pins upwards. Two rows of three pins each. Each row is for one channel.
Now for each channel, pins at your left hand side are 'CW' middle are 'W' and right hand side are 'CCW'

 

[TheCoolestOne]

Connecting POT to B1, om has explained already

Yes and it was easy to understand even for a newbie like me hyeah:. Pics would help reconfirm our connections before we power up.

 

[quad]

My confusion is how to connect the rotary switch to the input selector,

Here's one way -

 

[sachu888]

See this pic for volume POT connection:

Regards,
Sachin

 

[Santy]

Thanks sachin and quad
By googling to see if it was possible to stop the rotation at 5th position (in the 12 pos switch we have) I read that there must be a stopper pin below the nut, and it can be set to x position beyond which knob would not rotate. I have to check that out today.

 

[TheCoolestOne]

Here's one way -

Don't the ends of the Red and Green wire connecting to the SS Board OUT at point 1 & 2 have to be interchanged.

Somewhere ealrlier Sachin and Om mentioned that in the output connector of the source selector the channels were revesed.

 

[quad]

Don't the ends of the Red and Green wire connecting to the SS Board OUT at point 1 & 2 have to be interchanged.

Somewhere ealrlier Sachin and Om mentioned that in the output connector of the source selector the channels were revesed.

The left and right channels got reversed on output connector of the source selector - which
I have duly accounted for in the diagram I posted.
Note that left pin of the source selector output
is going to right channel signal input (not ground) and the right pin
of the source selector output is connected to the left channel signal input.

The VTA Preamp build below is an excellent reference
to show how to hook up the RCA jacks to the source selector.

SP14 preamp for BC

Use insulated RCA jacks so they do not make electrical
contact with the chassis.

Solder all the grounds of the RCA jacks together using a good
quality copper wire (one strand from a ethernet CAT5 or CAT6 cable will be great).

Connect this ground bus of the RCA jacks to ground terminal of
any of the inputs on the B1 board.

For each channel's input connector on the source selector board, Pin 1 goes to the
center lug of the Left channel RCA jack, and pin 2 to the center lug of the Right channel RCA jack.
You can use one strand of ethernet cable for these connections also.
Mount the source selector as close to the RCA jacks as possible - preferably directly
over the RCA jacks, as shown in the VTA preamp build in the link above.

 

[TheCoolestOne]

The VTA Preamp build below is an excellent reference
to show how to hook up the RCA jacks to the source selector.

SP14 preamp for BC

This is a really nice link and amazing illustrations. Very good for DIYers especially for wiring and connections.

 

[Santy]

Just like I expected, I was able to change the pin position of the switch to 5 and the knob stops rotating beyond that notch. Nice!

 

[jls001]

A couple of doubts about placement of components in B1:

1) Diode D1: is the direction of the diode correct in the picture?

2) Transistor Q100 and others: is the alignment of Q100 on the board correct?

Thanks in advance.

 

[sachu888]

A couple of doubts about placement of components in B1:

1) Diode D1: is the direction of the diode correct in the picture?

2) Transistor Q100 and others: is the alignment of Q100 on the board correct?

Thanks in advance.

Hi Joshua,
Diode and Jfets direction are correct.

Regards,
Sachin

 

[omishra]

Pune Guys! Please plan your pickup of R-Core from me.

For out station - Santy, keith_correa, apk, hydra and TheCoolestOne(2) will be dropped tomorrow. I will do required packing today. Sorry for the delay.

 

[TheCoolestOne]

Jls,

Both look correct to me.

 

[omishra]

Pune Guys! Please plan your pickup of R-Core from me.

For out station - Santy, keith_correa, apk, hydra and TheCoolestOne(2) will be dropped tomorrow. I will do required packing today. Sorry for the delay.

Transformers dispatched today - Santy, keith_correa, apk, hydra and TheCoolestOne (pair)

As per denom's instructions HemantWaghe's r-core handed over to ruenigma.

 

[jai1611]

I had B1 ordered the cabinet magma made last year for the group buy. Never got around to using it (still lying with magma). Do let me know if anyone is interested in it.

 

[jls001]

I had B1 ordered the cabinet magma made last year for the group buy. Never got around to using it (still lying with magma). Do let me know if anyone is interested in it.

The last time I was at his workshop I saw your cab. If you're not going to use it, I can buy it off you. Do let me know. May be I can even go pick it up from him tmrw.

 

[jai1611]

The last time I was at his workshop I saw your cab. If you're not going to use it, I can buy it off you. Do let me know. May be I can even go pick it up from him tmrw.

You can have it. I'll ask magma to give it to you.