B&K ST-140 convert to monoblock

[MuseChaser]

I had posted about this a while ago, but still haven't found anything definitive. I have two ST-140 amps and would love to convert them to a pair of monoblocks, as they were originally available as an option way back when. Does anyone have literature or the expertise to advise in specifically how to do so?

Thanks in advance for any help anyone can offer.

 

[tonesteroc]

I found this on another forum. I'm sure someone has probably done it on they're own. I couldn't find anything yet. https://forum.audiogon.com/discussions/i-have-two-b-k-st-140s-that-i-d-like-to-bridge if it's accurate, wattage would be the same. save one as backup or build a second system

 

[MuseChaser]

Thanks for the effort...much appreciated. I've been trying to find an answer, for a long time, as to what exactly the factory modifications were to make it a mono amp when that option was chose, but so far have come up empty.

Here's a link to as far as I've ever gotten on this search, from a bit less than a year ago...

[URL="https://audiokarma.org/forums/index.php?threads/b-k-st-140-conversion.992168/"]B&K ST-140 conversion?[/URL]

 

[David_NC]

Can you find schematics for them? If you can find them for your amps and the bridgeable ones, I'm sure that would shed some light on the differences.

 

[tonesteroc]

yeah I'm far from audiophile, but I have two rotel rb970bx amps bridged mono, why? only because there's a switch in the back. any benefit? I dunno.

 

[MuseChaser]

It's not a question of bridging the amps. As I explained in the posts from the link above, the mono versions retain the ability to handle less than 8 ohm loads, unlike the compromises incurred in bridging. I THINK two mosfets are used from the original second channel's board somehow.

 

[tonesteroc]

oh. I see. and you are correct.