adding a Power Amp

[johans]

hi guys,

i am using an SVT3-Pro head which for now is more than enough power for me, if in the long run i will need more power, instead of changing say to SVT4-Pro, i am thinking of getting probably a QSC power amp and run it through the SVT3-Pro ... what do you think?

is it possible to do that? i've never use any power amp before, can anyone told me how do you hook the power amp and SVT3-Pro? so i will still connect my speakers, my input jack as usual to the SVT3-Pro right? any of you have this kind of setup, an existing head + some power amp for more balls?

thank you guys

[Ben Clarke]

My angle is that to increase output, the best way to do so is at the speaker end.

In example, say you have a 300W amp. Pretty beefy, but you need more volume. You could pony up and buy a 600W amp. That's a lot more money, usually, and only buys you 3dB more output. Not much for your dollars. You could add a speaker, and gain maybe 5dB, with 3dB coming from the extra speaker, and the additional 2dB from increased power of most SS amp designs when operated at lower impedance soeaker loads. Again, not much for you money there, either.

In my mind, increasing the efficiency of the speakers you use can net you 10-15dB more output, and can be done rather inexpensively. The manufacturers don't want you to think this way, because your 1200W top of the line, high profit (nothing inherently wrong with that, BTW) monster amps suddenly become completely unnecessary for most of us.

[tkarter]

My angle is that to increase output, the best way to do so is at the speaker end.

In example, say you have a 300W amp. Pretty beefy, but you need more volume. You could pony up and buy a 600W amp. That's a lot more money, usually, and only buys you 3dB more output. Not much for your dollars. You could add a speaker, and gain maybe 5dB, with 3dB coming from the extra speaker, and the additional 2dB from increased power of most SS amp designs when operated at lower impedance soeaker loads. Again, not much for you money there, either.

In my mind, increasing the efficiency of the speakers you use can net you 10-15dB more output, and can be done rather inexpensively. The manufacturers don't want you to think this way, because your 1200W top of the line, high profit (nothing inherently wrong with that, BTW) monster amps suddenly become completely unnecessary for most of us.

What is the best way to increase your speaker efficiency?

tk

[Ben Clarke]

Ah, I thought my wording might be unclear there. Existing speaker cabs may be modified to increase efficiency by porting or otherwise increasing effective box size (to best take advantage of design parameters of the driver itself), but the highest efficiency can be obtained by using a driver of high sensitivity and horn-loading it. This is really the only way to get really high efficiency and maintain LF extension. In a direct-radiating design, there's always a balance to be struck between efficiency and LF extension, one at the expense of the other. Which is why we need big amps to drive the inefficient speaker designs common to the market today.

[Kennyhoe]

Are you already running the SVT-3 at 4 ohms? Poweramps aren't very expensive, you could get a QSC RMX 850 for around 3 bills. Then you would have roughly twice the power he has now with the option of adding extra speaker surface if you wanted to.

[Ben Clarke]

That's only $100 per dB.

[tkarter]

Thanks for the explanation.

tk

[Ben Clarke]

No problem.

BTW, my home stereo speakers are a 3-way, fully horn-loaded design, and put out 104dB with 1W input. They are unbelievably clear and undistorted with my 30W McIntosh tube amps. That's why I have this bias towards horn-loaded designs... It's not just max output, it's the lack of distortion at all levels that I really think is important. On the other hand, my B-15 can get a bit wooly at high volumes, so...

[technik]

I dont understand

[johans]

guys

thanks for all your help
but all your replies are far more complicated than what i asked for

now i am running svt3pro yes on 2 speakers, im just wondering in order to add up more power to my rig, yes i am looking at QSC RM850 or 1450, ... my question is ... How do you connect the power amp to the svt3? that's all

[Ben Clarke]

The expensive, easy way to go is just take a line from the pre out of the SVT ( I'm assuming it has one) to the input of the power amp, then out to your speaks.

[Ben Clarke]

Just looked at the specs of the SVT. You have a variable line level output. Use that output into the power amp and another set of speakers, then you're basically running two rigs, with seperate volume controls for each.

Still seems like along way to go to gain a few dB of output.

[johans]

by the way

anyone want to sell their rack cases?
i am looking for a 2 or 4 space, used is fine, as long the latches still good.

anvil, ata, grundorf, molded all are welcome ...
let me know

[technik]

The expensive, easy way to go is just take a line from the pre out of the SVT ( I'm assuming it has one) to the input of the power amp, then out to your speaks.

So let say he bought a power amp in e.g. 1000W, that means he will eventually get only the 1000W or 1000W + 450W (svt-3 pro) = 1450?

Because now we assume the svt3 as the pre-amp same as (svp-pro) right?

[xshawnxearthx]

you would plug it into the power section, just useing the svt 3 pro for the pre amp.


i am having the same problem. on my svt 3 pro, i have to shut off the eqbecause i am never happy with it on, and i just have the knobs on my music man in the halfway detent, because if i have it all the way up, my amp peaks out like woah.

so i have my gain like 1/4 and the volume cranking, along with the volume on my dbx662 up to like 3/4's it is still lacking a bit. if its mic'd no problem, if we are playing a hall, our an outdoor gig, it just suckkkkkks major ass.

im actually upgrading to the svt 4 pro, or the mesa 400+ i wan tto check out either or and go from there.