BA283 questions(mostly capacitors)
« on: May 20, 2014, 10:45:11 AM »
Now i'm building 1272 style preamp.BA283 is done.All components are ok but i'm confused about capacitors.

Should i use polystyrene capacitors? And why? For prototyping i'm using Wima polyester capacitors.Will this change sound?

There are 22uF 16v/25V and 330uF 4v electrolytic capacitors.Can i use all electrolytic capacitors 25v?

What about transformers?Can i use any 1:2 input transformer?

Why should i use 1:2 output transformer? What if i use 1:1?

Thanks.







Age Of Leviathans


ruairioflaherty

Re: BA283 questions(mostly capacitors)
« Reply #1 on: May 20, 2014, 12:15:10 PM »
There are literally hundreds of threads about these topics.  There has been a lot of discussion over the years on the cap topic with regards to Neve, the search will turn up lots of info.

Re the input transformer yes you can swap for another but in my opinion the Marinair/St Ives/Carnhill have a certain quality that is part of the Neve thing.

For the output transformer the Neve has special requirements because DC flows through the primary, search for combinations of "Neve, Gapped, LO1166" etc.



Re: BA283 questions(mostly capacitors)
« Reply #2 on: May 20, 2014, 12:38:08 PM »
There are literally hundreds of threads about these topics.  There has been a lot of discussion over the years on the cap topic with regards to Neve, the search will turn up lots of info.

Re the input transformer yes you can swap for another but in my opinion the Marinair/St Ives/Carnhill have a certain quality that is part of the Neve thing.

For the output transformer the Neve has special requirements because DC flows through the primary, search for combinations of "Neve, Gapped, LO1166" etc.

Thanks for reply.

I've already searched but i didn't find answer that what i want...

I neen specific answers about capacitors.
Age Of Leviathans

ruffrecords

Re: BA283 questions(mostly capacitors)
« Reply #3 on: May 21, 2014, 05:50:28 AM »
THe supply to the Neve circuits is 24volts. To be safe I would be tempted to use 35V working capacitors for the ones specified as 25V. A 330uF 25V is going to be a lot larger than a 330uF at 4V but if that is all you can get then it should be OK.

The reason the transformer is 1:2 is that this optimises the noise performance of the first stage. You can use a 1:1 but the noise performance will not be so good.

Cheers

Ian
www.customtubeconsoles.com
https://mark3vtm.blogspot.co.uk/
www.eztubemixer.blogspot.co.uk


'The only people not making mistakes are the people doing nothing'

Re: BA283 questions(mostly capacitors)
« Reply #4 on: May 21, 2014, 07:56:28 AM »
THe supply to the Neve circuits is 24volts. To be safe I would be tempted to use 35V working capacitors for the ones specified as 25V. A 330uF 25V is going to be a lot larger than a 330uF at 4V but if that is all you can get then it should be OK.

The reason the transformer is 1:2 is that this optimises the noise performance of the first stage. You can use a 1:1 but the noise performance will not be so good.

Cheers

Ian

Thanks you ruffrecords.

For now i will use radial capacitors.Other capacitors are tantal & polyester.After proto i will build 8 channels 1272.8 board and edge connectors are OK.When proto works,i will be ready to go 8 channels.
Age Of Leviathans