• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Why should I use two amps and how? Newb questions!

This gets to be about as clear as mud which is why I generally stay out of the bi-amping debates now but for some reason felt compelled today :headscrat.

Leaving out whether your filtering before the amps or using the speakers crossovers, a horizontal and vertical bi-amp config is what I previously described. Lets keep it simple: Vertical=1 STEREO amp per speaker (1 for the left speaker and 1 for the right speaker) (in this config the amps MUST be the same for obvious reasons or maybe not :D) SIMPLE. Horizontal=2 stereo amps for both L/R speaker but having 1 amp on the MF&HF and the other amp on the LF SIMPLE. Introducing monoblocs does not fall into these cofigurations.

At present I have monoblocs for each channel AND for each MF, HF and LF's of each speaker. Meaning I have 3 monoblocs per channel for a total of 6 monoblocs. This can not be called either vertical or horizontal.

Further muddying things some would argue that a TRUE bi-amp or tri-amp setup is ONLY achieved by filtering BEFORE the amps with no passive crossovers regardless of vertical or horizontal config or any others such as using monoblocs. So now we see passive bi-amping/tri-amping and active bi-amping/tri-amping and on and on etc. etc.
 
jchouston said:
Layman warning!

What, if any, is the benefit of running two similar amps from one preamp to one set of speakers?

If I were to get another GFA 535, would there be any benefit to incorporating it into my system and, if so, how do I do it? One amp per speaker? Or, one amp to the tweeters and one to the woofers? The 602’s do have two sets of posts per speaker, but I’ve never known why.

I’m just confused on how it would make a difference.

Two other factors: I have a pair of B&W 601’s that aren’t hooked up, but I don’t have wife approval for that yet. Also, would it make a difference if the second amp was an Adcom GFA 5300 instead of a GFA 535?

Thanks, everyone!
Click to expand...

This is just my opinion, so don't take it as gospel. I have great success using one pre-amp (with 'Y' adaptors) to run two seperate stereo amplifiers with each amplifier connected to it's own set of speakers (full range, not bi-amped). This just gives you twice the power and wattage than just using one amplifier.

Instead of four speakers connected to one amplifier (A+B speakers), you get less stress on the amps if you use just one set of speakers on each amplifier (A speakers only).

This may not be what you originally wanted to do, but like another person just said, It woul be easier to see what you want to do in person.

Some pictures (if possible) or diagrams, would be most helpful for everybody here trying to figure this out for you.
 
BalancedXLR said:
This topic has been beat to death and opinions vary. The 2 sets of binding posts are tied together with a jumper yes. By removing the jumper it seperates your speakers passive crossover. The top binding posts will connect to the MF&HF (mids and tweets) and the lower posts for the LF (woofers) (unless otherwise marked but I have NEVER seen different). Since you have 1 set of preouts, use some Y-adapters to split them. The amp hookup as you describe above will be what I would call a horizontal passive bi-amp configuration. Try searching the site on bi-amping, and you will get more info and opinions than you will have time for. HERE is some good reading for you.

IMO and for the most part if you really want improvements, look into REAL bi-amping or active bi-amping by filtering BEFORE the amplifiers taking the passive crossover's out of the equation. Keeping in mind there ARE some speakers that are best left using the speakers crossover. After you have researched and your head stops hurting have some fun experimenting. :D
Click to expand...


Good stuff.

I've seen that link before- it's informative in general, but he makes a few assumptions and leaves some info out.

Active bi-amping in this poster's case doesn't take the passive crossovers out of the equation unless they're physically removed from the signal path. I like leaving them in for beginners at first, it can reduce the damage mistakes might cause.

je
 
Exactly Fred which is why if you read the quote in your above post carefully, I said "By removing the jumper it seperates your speakers passive crossover. The top binding posts will connect to the MF&HF (mids and tweets) and the lower posts for the LF (woofers)" I never said REMOVED. The link of Rod's was merely a starting point and good reading. The inet is vast with lots of info of which some is BS and some is true :D

search, read, educate, learn, experiment and most of all have FUN!
 
If you have matched amps you may want to try Vertical over Horizontal because the amps are in total mono mode and I found it help the stage and image fill in the center, and I suppose this is because there is no channel crosstalk.
I have biamped several speakers in Horizontal with mismatched amps but always had either a crossover or a gain adjustment on atleast one amp.
 
BalancedXLR said:
Exactly Fred which is why if you read the quote in your above post carefully, I said "By removing the jumper it seperates your speakers passive crossover. The top binding posts will connect to the MF&HF (mids and tweets) and the lower posts for the LF (woofers)" I never said REMOVED. The link of Rod's was merely a starting point and good reading. The inet is vast with lots of info of which some is BS and some is true :D

search, read, educate, learn, experiment and most of all have FUN!
Click to expand...

I gotcha, I agree with what you're saying and I'm sure you know what you're talking about. I think the issue might be somewhat ambiguous language, which is a particular issue in any kind of technical writing. Looking at your post from the viewpoint of a beginner, this quote:

IMO and for the most part if you really want improvements, look into REAL bi-amping or active bi-amping by filtering BEFORE the amplifiers taking the passive crossover's out of the equation.
Click to expand...

...makes it sound like simply adding the active x-over before the amps nullifies the passive x-over's effects. Trust me, it's my nit-picking & not any kind of bad advice on your part. I'm just hoping to help keep it clear for others. I agree with the statement as you meant it, completely.

Like I said, all of this is easier to discuss than to type out...carry on! :thmbsp:

je
 
Layman warning, indeed!
Is this one version of bi-amping that has been described? Sorry for the mega-crappy illustration.
Someone advised to test whether the two amps(?) are in phase by reversing the speaker polarity then listening for improvement. Comments?
 
Your illustration is correct Spectrum. However I would label the + and - outputs on the preamp as LEFT and RIGHT and the same for the amps you labelled as adj. outputs as adj. inputs with LEFT and RIGHT instead of + and -
 
Fred Sanford said:
Huh?

:saywhat:

:headscrat

I think you're describing bi-wiring, but I'm really not sure.

:confused:

je
Click to expand...

Yeah I was not sure how to explain it and not sure if it would work,
that amp has a speaker A and B outputs couldn't he just use that one amp?
left channel A +/- would go to the LF +/- post and B would go to the HF +/- post
right channel A +/- would go to the LF +/- post and B would go to the HF +/- post
 
That could very well be done but that would be bi-wiring which is altogether different and brings about many opinions on its use also. Is this getting fun yet? :D
 
BalancedXLR said:
That could very well be done but that would be bi-wiring which is altogether different and brings about many opinions on its use also. Is this getting fun yet? :D
Click to expand...

Its a good job Iv got a hand full of pencils here or Id of never of remembered all of this :smoke:
 
Spectrum77 said:
Layman warning, indeed!
Is this one version of bi-amping that has been described? Sorry for the mega-crappy illustration.
Are split RCA cables commercially available?
Are these cables easy to home-brew? Any tips?
Someone advised to test whether the two amps(?) are in phase by reversing the speaker polarity then listening for improvement. Comments?
Click to expand...

Yes! I can't tell you how much more sophisticated your version looks than the one I scrawled on a note pad today. :)


The only difference is that, to my knowledge, the amps I'm referring to (Adcom GFA 535 and GFA 5300) don't have adjustable outputs and only have one set of outputs, at that.

I think I'd be running too many Y cables...

Thanks again, everyone. It's tough to learn this stuff in theory only and without practice.
 
jchouston said:
Yes! I can't tell you how much more sophisticated your version looks than the one I scrawled on a note pad today. :)


The only difference is that, to my knowledge, the amps I'm referring to (Adcom GFA 535 and GFA 5300) don't have adjustable outputs and only have one set of outputs, at that.

I think I'd be running too many Y cables...

Thanks again, everyone. It's tough to learn this stuff in theory only and without practice.
Click to expand...

Take a look at the Adcom GFA-2535 (essentially a double 535) as well, it's got the four amps you'd need in one chassis with level controls for each pair. I've got two of them, and use one to bi-amp JBL 4333As. They tend to go pretty cheaply, too.

I think you're wrong on the too-many-Y-cables- you'd only have two, on the preamp outputs.

je
 
Spectrum77 said:
Layman warning, indeed!
Is this one version of bi-amping that has been described? Sorry for the mega-crappy illustration.
Are split RCA cables commercially available?
Are these cables easy to home-brew? Any tips?
Someone advised to test whether the two amps(?) are in phase by reversing the speaker polarity then listening for improvement. Comments?
Click to expand...
The illustration below might be a lot easier to follow than your illustration.

 
Different amps have....

Fred Sanford said:
That depends- if there are strapped inputs on the speakers, chances are that all of the passive crossover circuitry stays in line once the straps are removed (no internal/external crossover switch on the speakers).

Don't know how the if-amps-aren't-the-same part enters into the equation...

je
Click to expand...

different levels of output. lets say you have a pioneer amp for one chanel, then an adcom on the other channel. they will sound different, one will have better control over bass, while the other will handle highs better, not to mention the midrange.
 
Originally Posted by Nailer
Seperate amp for the woofers will typically require a crossover if amps aren't the same.
Click to expand...

Originally Posted by Fred Sanford
That depends- if there are strapped inputs on the speakers, chances are that all of the passive crossover circuitry stays in line once the straps are removed (no internal/external crossover switch on the speakers).

Don't know how the if-amps-aren't-the-same part enters into the equation...

je
Click to expand...

Originally Posted by Nailer
Different amps have....different levels of output. lets say you have a pioneer amp for one chanel, then an adcom on the other channel. they will sound different, one will have better control over bass, while the other will handle highs better, not to mention the midrange.
Click to expand...

I'm still at a loss here- first you said that the woofers have their own amp, then you said each "channel" has its own amp (do you mean left and right, with two different brand/types of amplifier?). Either way, the passive crossovers are still in line in this example.

I agree that you'd want to have level controls on at least one of the amps you'd use, but an external crossover would not be "required" - is that what you meant?

je
 
OP...what is the goal you are trying to achieve?

If louder/more headroom has anything to do with it, "biamping" in this manner isn't the answer. For louder and or more headroom, you need bigger/more powerful amp.
 
You must log in or register to reply here.
Back
Top Bottom