Avondale Schottky Full Wave Bridge Module.....(Bargain)

[dazz lee]

https://avondaleaudio.com/store/#!/Avondale-Schottky-Full-Wave-Bridge-Module/p/37908426/category=0 Just fitted a pair of these in my Avondale 230se monoblocks wow what an uplift in clarity its one of those ha that's what it needed moments.

 

[earlofsodbury]

Convenient, but there's no data of any kind - no dimensions, no maximum ratings, nothing...

 

[OzBrit Audio]

What rectifiers did they replace Dazz. Standard 35A bridge I presume?

And how did they improve performance. Dynamics, bass slam, imaging? Tell please

 

[laverda]

Convenient, but there's no data of any kind - no dimensions, no maximum ratings, nothing...

Taken from the AA Store :The FWB2 is a direct replacement for the commonly found KBPC bridge rectifier without any change of wiring required.:

What more do you need to know! I believe the rectifiers used are MBRD10200CT. More info can be found on Avondale Audio's FB pages.

I can also confirm a very nice sonic uplift, more weight to the bottom end with low level detail being extracted and presented but the best bit for me is the musicality they impart. I still cant understand how they do this and or why, but they do.

 

[PaulMB]

I don't suppose this would "drop into" a standard NAP 180? Without messy mods? I've looked at photographs of its innards and don't see a "sugar-lump" rectifier with a screw in the middle. Maybe there is one, but hidden?

 

[Mike Hanson]

I don't suppose this would "drop into" a standard NAP 180? Without messy mods? I've looked at photographs of its innards and don't see a "sugar-lump" rectifier with a screw in the middle. Maybe there is one, but hidden?

I just looked a few pictures of the innards of the NAP180, and it appears to have some type of power supply board, so no FWB rectifier like this that I can see.

However, the NAP250 and NAP135 each have two onboard.

 

[GordonM]

I think the 180 is like the 140 which has two full wave rectifiers mounted on the under side of the power board, one either side.
The HiCap though has two of these KBPC rectifiers mounted on the floor of the sled, with wires soldered directly to the terminals.

I think Les assumes that people would know whither they fitted their Naim amp or not, but it would certainly help if he stated explicitly what models they fit, and the fact that you need two!

 

[chartz]

I have dozens of those diodes in a drawer. Perhaps I should sell them bridged
Expectation bias. Quieter background… sure.

 

[Mike Hanson]

I have dozens of those diodes in a drawer. Perhaps I should sell them bridged
Expectation bias. Quieter background… sure.

I think the benefit is the form factor, as a drop-in replacement. This is especially true if it's currently connected with spade terminals.

I have a buddy with a dual mono SE200 that I built for him, which uses a KBPC unit per channel. This might be a nice boost for him.

 

[PaulMB]

Thanks, all! I think in that case I'll leave the poor old 180 in peace.

 

[GordonM]

There was a thread on here with wiring arrangements for various Naim trannies but I can't find it now.
Naim appeared to use one secondary for the pos half cycle and the other secondary for the neg. Don't remember the explanation why.

 

[OzBrit Audio]

I have two implementations here for testing my Avondale builds

One is a test chassis with a 800VA tiger torroid, twin secondaries, 35A conventional bridge rects and single Kemet 22000uF Kemet caps. The second is a 'proper' box but build yet to be finalised, config Canterbury Windings 600VA twin secondaries, Minicap6's with 10A Schottky and bank of 3 x 10000uf Nichicon Caps.

When switching boards between the two the Minicap6 configuration sounds better. More cohesion to the music. How much is due to the rectification I don't know but I can definately hear a difference.

Note the wiring with the Minicap6 is much better, shorter wires to the amplifier boards whereas my test chassis is a little 'birds nested' for want of a better term.

 

[OzBrit Audio]

Note I think Avondales latest boards with SMD Schottky's are latest generation which have improved performance over the ones I have in my Minicap6 for example and also the T0220 devices in the Cap6's. This may also be a contributing actor?

 

[James Evans]

I suppose my qudos amp is a candidate for trying one of these out. It currently has a standalone mbr20200 based bridge so would be relatively easy to swap that out and plug one of these in.

 

[davidsrsb]

You have to watch reverse leakage in higher voltage Schottky diodes. It can cause a thermal run away.

 

[martin clark]

You have to watch reverse leakage in higher voltage Schottky diodes. It can cause a thermal run away.

That's an interesting idea I'd never have thought-of. So I looked-up the datasheet, for the part suggested above, a 200v PIV part: so the upper limit you'd want to run it at, is c 60-65vDC output. At low temps/moderate forward current: no issue whatsoever.

Run the diode hot - c 120degC - the reverse leakage current is specified at up-to 25mA; and at sim forward DCv, that's 1.7w dissipation, from leakage, in a surface-mount part at the criterion above. Wow; yes - it might run-away, without a bit of thought!




NB: for the wider discussion: this is nothing to do with, nor a slight-upon, the Avondale implementation, whatsoever


PPS: IR thermometers are so dirty-cheap these days, and so useful - I'd suggest it's right up there after a a good soldering -iron and 2+ DVMs, as a DIY'ers most useful tool: to check out duff parts-in-circuit, incorrect bias, ..oh- so many comparable things.

 

[muchtoofast]

Taken from the AA Store :The FWB2 is a direct replacement for the commonly found KBPC bridge rectifier without any change of wiring required.:

What more do you need to know! I believe the rectifiers used are MBRD10200CT. More info can be found on Avondale Audio's FB pages.

I can also confirm a very nice sonic uplift, more weight to the bottom end with low level detail being extracted and presented but the best bit for me is the musicality they impart. I still cant understand how they do this and or why, but they do.

It will be interesting to see how these fair in your hicap clone with the Avondale shunt if you are still intending to do that. Thanks for the details.

 

[davidsrsb]

Run the diode hot - c 120degC - the reverse leakage current is specified at up-to 25mA; and at sim forward DCv, that's 1.7w dissipation, from leakage, in a surface-mount part at the criterion above. Wow; yes - it might run-away, without a bit of thought!

NB: for the wider discussion: this is nothing to do with, nor a slight-upon, the Avondale implementation, whatsoever

Yes, I am not targeting Avondale. I am highlighting that "they are quieter" simply swapping to Schottky diodes requires some thinking and testing. SMD is even trickier as so much of the power dissipation is into the tracks and copper zones. The datasheet describes rating the part on an metal core PCB. A thermal camera is a good idea.

 

[earlofsodbury]

Why even use SMD in a potentially high-dissipation application like this? Sure Avondale have (presumably) done the calcs for its intended application - but by not making the module more flexible in its potential applications you limit your market to exclude all the rest of the non-Avondale DIY market.

 

[davidsrsb]

THT parts are going obsolete very fast