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Bridging an amplifier

I recently watched a YouTube video, a few years old, that featured Flemming Rasmussen, the highly regarded founder and engineer for Gryphon (now retired I believe). Flemming was speaking of his class A monoblock amplifiers in the Antileon Evo, Colloseum and Mephisto. Flemming was expressing his disdain for Monoblocks that are actually 2 internally bridged amplifiers, (such as DNA 500,Clayton M300s and also class A Luxman that can be used as Monoblocks in the BTL mode (bridged tied load), calling these types of Monoblocks inferior and not true Monoblocks. He claims dedicated Monoblocks where all push pull transistors are paralleled, are vastly superior to summing the two channels via bridging (antiphase summing). I’d love to know if most audiophiles and engineers agree with Flemming. I have owned and found both the DNA Monoblocks and Clayton M300 Monoblocks to sound excellent, and a friend uses two M-800A Luxman class A amplifiers in bridged tied load mode (BTL switch) with great clarity and power. Thank you for your thoughts!
audiobrian

Showing 6 responses by georgehifi

georgehifi's avatar
georgehifi
10,312 posts
 
and others build dedicated bridged amplifiers
Yes a dedicated bridged mono block amps, but not stereo amps that have just been bridged, just to gain more wattage.
There is a big difference in how they will both perform. Re first post (Gryphon’s Flemming Rasmussen) and Almarg’s 5 post down.

The point here is, members are looking to bridging their stereo amps getting another one and doing the same, you end up with a pair powerful PA type amps where you once had quality stereo amps, and what Odyssey does with their monoblocks just their stereo amps bridged, or they used to be when the AU agent showed me the insides.

Cheers George
georgehifi's avatar
georgehifi
10,312 posts
 


You being also a "fuser" have no idea about EPDR either. 
That's why the Wilson Alexia has one of the evilest loads in the bass ever for an amp to see My friend Edgar Kramer Editor of Soundstage Australia has a pair and has proved it to himself/us and others with all kind of amps he's tried on them. As well as just about every other publication.
Take away the  -43' phase angle and you have doubled the impedance, and made it far better load for an amp to see. https://ibb.co/YPF52Mw
 But not you, you know more than anyone.!  
georgehifi's avatar
georgehifi
10,312 posts
 

All you have to do is read techs with far more savvy than you on the subject in Google, and now your even saying you’ve got more than Almarg (rip) as well, your are a genius!!! well self proclaimed one at best
georgehifi's avatar
georgehifi
10,312 posts
 
Please explain if you disagree, I’m kinda new to this :)
Just search Google "cons of bridging amplifiers" or "disadvantages of bridging amplifiers" there’ll be pages and pages to read.

Looking at the Luxman’s M-900u specs, doesn’t it still have great specs when used as a monoblock?
If they put them in print, only the ones they want you to see.

Almarg (rip) will also tell you the cons. https://forum.audiogon.com/posts/1762093

Cheers George
georgehifi's avatar
georgehifi
10,312 posts
 
It's all out there to search, Al has also given some good info on it as well, above. If all you need is watt's then bridging is the way to go. 

Cheers George
georgehifi's avatar
georgehifi
10,312 posts
 
audiobrian
Flemming was expressing his disdain for Monoblocks that are actually 2 internally bridged amplifiers

Flemming is right, and these are these are the reasons for not bridging amps.


  I’ve said it before in other threads here it is again

"Nice amp, if you want to hear them at their best, don’t bridge "if there’s no need to", as all you’ll gain is watts, everything else takes a hit when you bridge amps.

Pro’s=
More watts.

Con’s=
Worse damping factor
Higher output impedance (has relevance to damping factor)
Lower stability (especially into low impedance’s)
Current ability is reduced (especially into low impedance’s)
Higher distortion.

And if you have two of them better to run them in stereo mode and vertically bi-amped, instead of bridging (mono’ing).
http://www.av2day.com/wp-content/uploads/2014/05/biamp2.jpg"

Cheers George
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