pre-amp to power amp

[baldlobo]

ok, would running audio out on a pre-amp(that is amped 10w rms) to a power amp of ¡Ü wattage 1)cause distortion?(would distorion be caused by using the amps in series), 2) increase dbls significanly(or modified to increase dbls), 3) increase wattage to speakers?


thanks for any info

 

[Bill Fitzpatrick]

What's a "dbls" ?

 

[Upupa Epops]

" dbls " = probably decibels

 

[AndrewT]

Hi Baldlobo,
could you rephrase your Qs. I (& maybe some others) am having trouble understanding what you want.

 

[pinkmouse]

I think he wants to plug the output of a smaller power amp into the input of a larger one, to get more power than each one individually.

But I could be wrong.

 

[planet10]

Originally posted by pinkmouse
think he wants to plug the output of a smaller power amp into the input of a larger one, to get more power than each one individually.

If that is the question, then the answer is no... worst case he may let some smoke out...

dave

 

[baldlobo]

I think he wants to plug the output of a smaller power amp into the input of a larger one, to get more power than each one individually.

But I could be wrong.

basically, yes that's what I want to do.

If that is the question, then the answer is no... worst case he may let some smoke out...

dave

then answer me this then, why on some of the other boards say you can. I'll supply links

 

[pinkmouse]

I'll supply links

Please do! No disrespect to you, but there is a lot of nonsense on the internet, and it looks like you have found some prime examples. However, you've come to the right place to get decent advice now.

 

[kafka]

I don't think anybody wrote something like that. You might have misunderstood something. You can for example use headphone amp as a preamp, but it is't connectes with increasing the output power.

 

[planet10]

then answer me this then, why on some of the other boards say you can. I'll supply links

It can be done... to be safe using attentuating Rs (exactly what plate amps do if you are using the speaker level inputs), but you get only the power output of the 2nd amp. In this case the 1st amp still sees a real load as well, with just a trickle bleed off to feed the sub amp.

dave

 

[digi01]

ok, would running audio out on a pre-amp(that is amped 10w rms) to a power amp of ¡Ü wattage 1)cause distortion?(would distorion be caused by using the amps in series), 2) increase dbls significanly(or modified to increase dbls), 3) increase wattage to speakers?

what your mean is run a power amp at pre amp mode?

 

[G4ME]

if you can tap into the pre amp of the first amp and sent it to the power amp you would be fine.

But if you are just trying to make your system louder, the power amp (guessing a pro amp) that you use can only take a certain input signal, anything over that signal, say 10V is just gonna drive the power amp to clipping.

you can't cascade amps to make the signal louder, the final output wattage is souly determined by the max input signal it can take (2V pp prob normal) and the power supply and the rating on the output transistors.

 

[imix500]

Perhaps he saw some info on a ham or rf site? It's quite common to drive large rf transmitters with a smaller amp, but that is equivalent to us using a preamp to provide the proper drive voltage at a given impedance to an af amplifier.

 

[baldlobo]

ok, here is what I want to do; using the existing 6 outputs from the preamp(that has 10w rms) and run it in to a separate amp for each channel; so from the feed back I've recieved the wattage is not added together(correct?), and that in order to use the outputs, I'd have to place a resistor(in each channel) to bring the voltage down to where it would end up being exceptable as input(correct?)


ps. never post half baked

 

[planet10]

Perhaps he saw some info on a ham or rf site? It's quite common to drive large rf transmitters with a smaller amp, but that is equivalent to us using a preamp to provide the proper drive voltage at a given impedance to an af amplifier.

Or like using a 300B to drive an 845 (or as Jeff did recently a KT88 to drive a 2A3)...

dave

 

[rev_psilocybe]

Perhaps he saw some info on a ham or rf site? It's quite common to drive large rf transmitters with a smaller amp, but that is equivalent to us using a preamp to provide the proper drive voltage at a given impedance to an af amplifier.

Seems the most likely to me. I've actually been reading up on low power FM broadcasting and antenna theory these last few days and most manufactured broadcast amps of 15W and higher actually have to be driven with a lower power broadcast amp, some as high as 6W...give me line level any day.