B1 builders thread

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Hi all, would this be an appropriate "first build" for a novice DIYer? I don't have any background in electronics so it will be a complete learning experience. Haven't come across many first projects that I could call both useful & easy to build. This will fill a hole in my system and help me on my way to more complex projects (I hope?)

Thoughts?

If it's good, can anyone point me in the right direction as far what you recommend I read prior to beginning? Does PassDIY supply a BOM with the board when you buy at their site?

Thanks guys.
 
BTW I am looking for transformer- 18 v transformer is recommended. Marra, which model would suit better- as there more different numbers, like VA etc ?
And in UK what is a better place to shop online- rs, mouser , farnell ? In some of them I can buy in bulk only and delivery charges quite high :)
 
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A transformer with 12V secondaries would be best as you would end up with about 18V dc [12x1.4].I used 50va but only because I already had one.15-30va I think would be more than adequate.Someone with more nouse than I will no doubt chip in.
Nelson recommends a wallwart supply so if you have a laptop charger that outputs 18v dc that would be the simplest answer.
I usually use Farnell but sometimes you have to buy 50 of something especially resistors or if I want something "audio grade" HiFi collective.

Happy New Year.
 
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BTW I am looking for transformer- 18 v transformer is recommended. Marra, which model would suit better- as there more different numbers, like VA etc ?
And in UK what is a better place to shop online- rs, mouser , farnell ? In some of them I can buy in bulk only and delivery charges quite high :)

This one is easy. go to the the local thrift shop and find an old HP laser printer. The power supply (wall wart) are usually the correct voltage (they will be marked on the PS case). Do not worry about the VA since the B1 draws very little current. I got mine for $5 and there are a ton of these avaliable.
 

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Hi all, would this be an appropriate "first build" for a novice DIYer?

Yes, it's a great and simple project.

If it's good, can anyone point me in the right direction as far what you recommend I read prior to beginning?

The link Marra suggested are the most important.
Here is a decently-illustrated thread - http://www.diyaudio.com/forums/pass-labs/181552-b1-preamp-build-thread.html

Does PassDIY supply a BOM with the board when you buy at their site?

Unfortunately no. But the best thing is to learn to work from a schematic. BUT that's not always possible as you need to take things like lead spacing into consideration... Look at various threads on the B1, and you will start to see how other people put them together.

Also do not hesitate to ask for assistance on the threads! Lots of people here who are willing to help. That's what the forums are all about :D :D :D :D :D
 
A transformer with 12V secondaries would be best as you would end up with about 18V dc [12x1.4].I used 50va but only because I already had one.15-30va I think would be more than adequate.Someone with more nouse than I will no doubt chip in.
Nelson recommends a wallwart supply so if you have a laptop charger that outputs 18v dc that would be the simplest answer.
I usually use Farnell but sometimes you have to buy 50 of something especially resistors or if I want something "audio grade" HiFi collective.

Happy New Year.
12 x 1,4 = 16,8 v. It's not a bit low ?
 
In my experience a nominal 12Vac secondary tends to give about 17.5-18.5Vdc in the UK, as transformer ratios are set for a 230Vac supply but we tend to get 240Vac (or more!).

For my last couple of B1 buffers I ended up going with a cheap 24V external SMPS (the in-line type designed for powering LED lights - less than £10 on eBay) and then increasing the first series R at the B1 PSU. Given the low current draw of the buffer a nice CRCRC with 3-10ohm resistors and low ESR caps will make the DC plenty quiet enough. Certainly better than risking 50/100Hz hum by putting a linear supply in the buffer enclosure, in my experience.

Universal DC 24V LED Driver Power Supply for Light Strip CCTV Waterproof Outdoor | eBay
 
Forgot to say that with 24V on hand you can up your series resistance as required to get to the voltage you want for the buffer. The more resistance, the more immunity from the smps noise. Make the last cap after the series R a biggy (>10000uF) but choose lower capacity caps with lower impedance at high frequencies for the first in the line after the smps.
 
Forgot to say that with 24V on hand you can up your series resistance as required to get to the voltage you want for the buffer. The more resistance, the more immunity from the smps noise. Make the last cap after the series R a biggy (>10000uF) but choose lower capacity caps with lower impedance at high frequencies for the first in the line after the smps.
thank you for the explanation !
 
Can anyone comment on using a digital (pga2310 or like) attennuator and source selector with the b1?

Sound quality wise?

I have had difficulties with my lightspeed attennuator, especially in balancing between channels... Would rather use something else for my next build.

Hi

I've been creeping up on doing this to my B1 for quite a while but stuff just keeps getting in the way, so I can't answer the question directly as it's not finished, apologies. I am curious however, why do you look at something like the pga2310 in preference to an attenuator such as mcp4241 which is nearly 20 times cheaper(well it is in the uk)

I will post listening findings as soon as it's finished.

Ed
 
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