Bridge rectifier

All general audio posts go here.
User avatar
Latteman
Posts: 1220
Joined: Tue Aug 14, 2018 7:20 pm
Location: S. Yorkshire
Has thanked: 553 times
Been thanked: 297 times
Contact:
Great Britain

Bridge rectifier

Unread post by Latteman »

I was browsing eBay- as u do on days off and spotted this- 2 bridge rectifiers- can’t tell if they are series or parallel - what is the purpose here?
Image
Analogue Source -
Denon DP47f- Ortofon mc20 supreme
Ifi Zen Phono
Doug Self balanced Pre amp
Akai 4000DS mk2 R2R
Digital Sources- IfI stream, Ifi Neo idsd Dac; Tidal / Radio Paradise
Amplification Nva 30vdc mono blocks
Speakers Lii Audio F-15 in Open Baffle; Ls6
Weiduka AC8.8- for digital sources
Mini BMU for analog sources

Daniel Quinn
Posts: 8586
Joined: Thu Jul 12, 2012 7:16 am
Has thanked: 24 times
Been thanked: 399 times

Re: Bridge rectifier

Unread post by Daniel Quinn »

Is it not a stereo amp as opposed to monoblock

valvesRus
Posts: 562
Joined: Sat Feb 24, 2018 2:34 pm
Has thanked: 25 times
Been thanked: 63 times
Great Britain

Re: Bridge rectifier

Unread post by valvesRus »

Latteman wrote: Mon Mar 30, 2020 10:23 am I was browsing eBay- as u do on days off and spotted this- 2 bridge rectifiers- can’t tell if they are series or parallel - what is the purpose here?
Image
Is it a split rail power supply ?

User avatar
scotty38
Posts: 301
Joined: Sat Jan 20, 2018 12:51 am
Has thanked: 9 times
Been thanked: 4 times
Kiribati

Re: Bridge rectifier

Unread post by scotty38 »

I'd have said separate power supplies too. It may be my eyes but it doesn't look like it's wired up from here.....

User avatar
Latteman
Posts: 1220
Joined: Tue Aug 14, 2018 7:20 pm
Location: S. Yorkshire
Has thanked: 553 times
Been thanked: 297 times
Contact:
Great Britain

Re: Bridge rectifier

Unread post by Latteman »

Image
Analogue Source -
Denon DP47f- Ortofon mc20 supreme
Ifi Zen Phono
Doug Self balanced Pre amp
Akai 4000DS mk2 R2R
Digital Sources- IfI stream, Ifi Neo idsd Dac; Tidal / Radio Paradise
Amplification Nva 30vdc mono blocks
Speakers Lii Audio F-15 in Open Baffle; Ls6
Weiduka AC8.8- for digital sources
Mini BMU for analog sources

29mile
Posts: 142
Joined: Thu Jul 12, 2012 1:20 pm
Has thanked: 1 time
Been thanked: 23 times

Re: Bridge rectifier

Unread post by 29mile »

They look in parallel to me and as per by listing ( now ended ) boards were replaced by NVA at some point.

https://www.ebay.co.uk/itm/NVA-A60-Powe ... true&rt=nc

User avatar
karatestu
Posts: 5945
Joined: Sun Jan 08, 2017 4:40 pm
Location: North Yorkshire
Has thanked: 1865 times
Been thanked: 1378 times
Great Britain

Re: Bridge rectifier

Unread post by karatestu »

Most power amplifiers have split rail power supplies. NVA amp boards need a split rail psu (positive & negative voltage)

That amp in the picture is a stereo amp. The transformer has two secondary windings which have two wires joined to give a centre tap.There are only two smoothing capacitors (the big ones in bottom right corner) - one supplying positive voltage for both amp boards and one supplying negative voltage to both amp boards.

The two rectifiers look to have their AC voltage inputs joined with short wires. The positive DC is taken from the rectifier closest to the transformer and the negative DC is taken from the one further away from the transformer.
DIY FREE ZONE

idem-zalp
Posts: 5
Joined: Fri Apr 08, 2016 12:22 am
Location: Greenwich
Has thanked: 0
Been thanked: 0
Ukraine

Re: Bridge rectifier

Unread post by idem-zalp »

"The positive DC is taken from the rectifier closest to the transformer and the negative DC is taken from the one further away from the transformer."
Each bridge rectifier works as "half-bridge" - think about what it does to the output frequency
Current setup: Elex / Dynaudio

Lurcher300b
Posts: 933
Joined: Tue Jun 14, 2016 1:58 pm
Has thanked: 0
Been thanked: 16 times

Re: Bridge rectifier

Unread post by Lurcher300b »

Each bridge rectifier works as "half-bridge" - think about what it does to the output frequency
Nothing, it will still be 100Hz (in the UK at least).

Its probably wired like this:

Image

User avatar
savvypaul
Posts: 8635
Joined: Tue Oct 11, 2016 7:14 pm
Location: Durham
Has thanked: 1657 times
Been thanked: 2978 times
Contact:
Great Britain

Re: Bridge rectifier

Unread post by savvypaul »

Speaking with Tomasz, he's not seen that particular bridge rectifier arrangement on any of the NVA amps he worked on. Richard must have had his reasons, though...assuming it was his work.
I am in the hi-fi trade
Status: Manufacturer
Company Name: NVA Hi-Fi
https://nvahifi.co.uk/

Post Reply