Explanation of bridging amps

snake1

I basically know what bridging does but now that I look a the back of an actual 2ch that can do it, I'm not sure how to hook it up. I'm attaching a pic of one so that if someone can explain, then they can use something I can see (visual learner).

BlueFox

From the manual, page 6

Mono Input and Speaker Connections
1. Turn the unit off and remove the AC cord.
2. Connect the single cable from the preamp or controller to the R channel Input jack.
3. Set the Bridging switch to its Mono position.
4. Connect the positive lead of the speaker wire to the red R + channel speaker pair A terminal.
5. Connect the negative lead of the speaker wire to the red L + channel speaker pair A terminal.
6. Do not connect anything to either the L - or R - speaker terminals.
7. If you have a second mono speaker repeat steps 4 - 6 with the speaker pair B terminals
8. Reconnect the AC cord.

http://www.parasound.com/pdfs/OWNER_GUIDE_2125.pdf

Google is your friend.

snake1

I read that very thing, but still wrapping my head around it. Humor me here. To bridge this particular amp for its 400 rated watts, you just hook it up as this states and hook it to one speaker? The other speaker pair will be empty? If i want another 400w to the other speaker, I would get another identical amp, run the same instructions but this time hook it to the L channel input? I know I'm probably asking the same thing over and over but it helps me understand.

F1nut

To bridge this particular amp for its 400 rated watts, you just hook it up as this states and hook it to one speaker? The other speaker pair will be empty? If i want another 400w to the other speaker, I would get another identical amp, run the same instructions but this time hook it to the L channel input?

Correct. You basically end up with two mono blocks. However, bridging isn't all it may seem to be. You actually lose a bit of headroom, generally have higher distortion levels and only gain a few dB in SPL. You're better off getting one good stereo amp or two actual mono blocks.

heiney9

^^ +1

stretchl

Question -

Is "bridging" the same thing as "bi-amping?"

tonyb

stretchl wrote: »

Question -

Is "bridging" the same thing as "bi-amping?"

No....

Bridging is taking a 2 channel amp for example and making it a one channel amp at almost double the power.

Bi-amping is taking 2 amps, and connecting to one speaker by way of an external crossover. Some variations of this exists but one is to use a 2 channel amp per speaker connecting each channel to the top and bottom posts of the speaker.

snake1

Thanks for the explanation fellas!!

snake1

F1nut wrote: »

Correct. You basically end up with two mono blocks. However, bridging isn't all it may seem to be. You actually lose a bit of headroom, generally have higher distortion levels and only gain a few dB in SPL. You're better off getting one good stereo amp or two actual mono blocks.

Is this an 'across the board' problem or just with ones you've personally heard?

stretchl

tonyb wrote: »

No....

Bridging is taking a 2 channel amp for example and making it a one channel amp at almost double the power.

Bi-amping is taking 2 amps, and connecting to one speaker by way of an external crossover. Some variations of this exists but one is to use a 2 channel amp per speaker connecting each channel to the top and bottom posts of the speaker.

OK... I just gotta spend some time getting my head around this...

nhhiep

snake1 wrote: »

Is this an 'across the board' problem or just with ones you've personally heard?

it depends on how they designed the amp. I know all of my HK Citation 7.1 amps sound as good as bridge mode. In fact, they designed it with bridging in mind according to the manual, resulting in the THD stays the same .003 from 20-20khz, but with more current when bridged.

Joe08867

I have heard amps designed with Bridging in mind and while they do sound better than other amps bridged they still loose a bit of headroom. The nuance from silence to loud is smeared a bit in bridged mode.

I only bridge amps for subwoofer use. I have tried several amps in bridged mode full range and never felt the added watts were worth the trade off in quality of sound. Citation included as well as Rotel, Parasound and B&K. They sound better as they are intended, not bridged.

heiney9

nhhiep wrote: »

resulting in the THD stays the same .003 from 20-20khz,.

That right there tells you absolutely nothing about how an amp will sound, so just because they were able to measure the same (in bridged and stereo) means absolutely nothing.

H9