Power Amps

[King of Loss]

Right, I udnerstand that you need a preamp with some sort of EQ section, a gain, and a master volume/output to plug your bass into. This then goes into the poweramp, which goes to speaker cabinets.

Now, what does it mean when you look at a poweramp description and it says it is a "2x50 watt poweramp" or "2x 150 watt" etc? Does this mean 100 watts/300 watts total output, or does it mean two channels that each run 50/150 watts at any one time?

Here is an example:

[url="http://www.basscentre.com/cat/product_info.php?cPath=39&products_id=1405"]http://www.basscentre.com/cat/product_info...roducts_id=1405[/url]

As you can see, it says it runs 2 x 425W @ 4 ohms. 2 x 500W @ 2 ohms. OR 1000W mono bridged @ 4 ohms. Does this mean it can have two channels at 425 watts at 4 ohms, or ONE channel at 1000W at 4 ohms?


Sorry if I am not being very clear. Basically I want to know how poweramps work, and how the whole "mono/stereo" thing works with poweramps. It seems like quite a simple question, but I am used to an "all in one" head/combo.

Thanks,


Daniel

[The Funk]

Well, I don't understand the question. It looks like you sort of answered it yourself.

Stereo = 2 independent channels. Mono = 1 channel. Dual Mono = 2 channels from 1 input source.

So, 2 x 450W = 2 channels which each pump out 450W. 1000W Mono Bridged = 1 channel which pumps out 1000W.

Where it says you have the option of either 2 x 450W or 1000W Mono Bridged, it means there's a switch you can press which changes it from Stereo to Mono.

[King of Loss]

Alright, that's basically all I wanted to know. Why would someone want to have two channels, though? IF they had two different preamps I guess?

You're right, I kinda did answer it myself, I was just making sure. Now this thread can probably sink into the depths of the forum

[The Funk]

Ah, well, if you go Dual Mono, you can use two different bass cabinets and control the output volume of each seperately - handy if the cabs are different. You could emphasise the low end or high end or midrange and balance the two cabs with the volume controls.

Then, if you go Stereo, you could bi-amp - splitting the frequencies output by your preamp using a crossover - and then sending each to a dedicated cab.

[Dood]

[quote name='The Funk' post='37438' date='Jul 26 2007, 05:08 PM']Ah, well, if you go Dual Mono, you can use two different bass cabinets and control the output volume of each seperately - handy if the cabs are different. You could emphasise the low end or high end or midrange and balance the two cabs with the volume controls.

Then, if you go Stereo, you could bi-amp - splitting the frequencies output by your preamp using a crossover - and then sending each to a dedicated cab.[/quote]

Can I just clarify. With a stereo power amp you can go dual mono, Bi amp or stereo using the 2 channels. (Bi-amp and Stereo being 2 different setups) The last meaning that you can run 2 full range channels using stereo FX like ping pong delays, reverbs, panning effects and choruses. Once you go stereo, you'll never wanna go back! ;o) (especially if you are an ERBer!)

[King of Loss]

[quote name='dood' post='37452' date='Jul 26 2007, 05:51 PM']Can I just clarify. With a stereo power amp you can go dual mono, Bi amp or stereo using the 2 channels. (Bi-amp and Stereo being 2 different setups) The last meaning that you can run 2 full range channels using stereo FX like ping pong delays, reverbs, panning effects and choruses. Once you go stereo, you'll never wanna go back! ;o) (especially if you are an ERBer!)[/quote]


Why would the stereo thing matter, at all, if your cabs will be on top of each other? Surely if this is the case, stereo effects etc will be cancelled out?

Or are there seperate line outs to the PA for each channel, meaning that the mixing board has two bass channels?

Thanks for the help guys.

[Dood]

Nah the effects wont be cancelled out. Not only that.. the cabs needn't be on top of each other. ;o) One either side of the drummer! lol

[Dood]

oh.. and yes, you could always take a stereo DI to FOH .. I have a little DI box that I carry with me for that.

[King of Loss]

[quote name='dood' post='37460' date='Jul 26 2007, 06:00 PM']Nah the effects wont be cancelled out.[/quote]
Haha, I think I misrepresented myself. I meant the effect of getting "stereo delay" etc would be cancelled out, as the speakers would have little distance between them. Not the whole effect being removed, haha.

Cheers for the help

[Dood]

no wurriezz! ;o)

[The Funk]

[quote name='dood' post='37452' date='Jul 26 2007, 05:51 PM']Can I just clarify. With a stereo power amp you can go dual mono, Bi amp or stereo using the 2 channels. (Bi-amp and Stereo being 2 different setups) The last meaning that you can run 2 full range channels using stereo FX like ping pong delays, reverbs, panning effects and choruses. Once you go stereo, you'll never wanna go back! ;o) (especially if you are an ERBer!)[/quote]

Clarification noted. I shall be more precise with the terminology in future. But now you've got me thinking about stereo effects!

[Oxblood]

Hi King of Loss,
I would just add what you probably know already: bridging the outputs of a stereo/2-channel amp can only be done with an amp like the one you've been looking at - i.e. one that is designed to be bridgeable.

Just in case anyone out there gets a burning (good choice of word!) desire to common up the outputs of any old stereo amp. Bad idea!

Edited July 27, 2007 by Oxblood