Receiver as preamp. Hook-up???

[ghardenb]

I am contemplating adding a 2-channel power amp, then using my HT receiver as a preamp but leaving the surround speakers hooked directly to the receiver.

I don't understand the volume control relationship between a receiver (preamp) and power amp. Does the amp's strength augment that of the receiver so that, for example, setting the receiver volume at 1/3 will produce greater output to the speakers than did the same setting when there was no amp? If this is the case, then how is a balance kept between the fronts and surrounds?

Also, my powered sub is now into the dedicated sub-out on the receiver. Will it be more desireable to run it through the amp, which I expect will have greater power and range than the receiver? Will a stereo power amp accomodate this?

Help will be appreciated!

Gary

 

[Mr.T]

I am contemplating adding a 2-channel power amp, then using my HT receiver as a preamp but leaving the surround speakers hooked directly to the receiver.

I don't understand the volume control relationship between a receiver (preamp) and power amp. Does the amp's strength augment that of the receiver so that, for example, setting the receiver volume at 1/3 will produce greater output to the speakers than did the same setting when there was no amp? If this is the case, then how is a balance kept between the fronts and surrounds?

Also, my powered sub is now into the dedicated sub-out on the receiver. Will it be more desireable to run it through the amp, which I expect will have greater power and range than the receiver? Will a stereo power amp accomodate this?

Help will be appreciated!

Gary

Gary,
I think, it would have been more helpful to us in order to help you better, if you would have included in your thread, brands and model numbers of your HT equipment.

I personally don't think is a workable idea to add an amp to your system to gain additional punch to your speakers eventhough we don't know what kind of speakers you have. As you might know usually a good 2 channels 100W per channel amp will cost a good amount of money, besides the fact that your speakers might not be good enough to withstand all this power.

Please give us more infos about your HT system, before a sensible conversation could be carried on.

 

[Mudcat]

With my system (Yamaha RX-V1400, 6 Alesis pro amps), the amps do not increase the volume over what the Yamaha is set too. The Alesis amp manuals tell you to set the volume to max and to use the pre amp to control the volume. This works well in my system without lose of YPAO or other functions of the Yamaha.

http://www.audioholics.com/forums/showthread.php?t=2380

 

[hopjohn]

If I understand you correctly, in the first part of your question you just want to know if the amp plays louder at the same volume before and after adding an amp.

I'm not 100% certain but I believe if you buy an amp whose per channel wattage is greater than that of your per channel wattage in the receiver it should play louder with the amp added with the volume knob at a given level. To be honest it's really not all that important to add a two-channel amp unless you are noticing strain, clipping, or excessive heat from your receiver.

The second part of your question about level matching is pretty simple. You would set your system to around 75 to 80 db using a sound level meter at the listening position. Then, using the level controls on your receiver, you would just balance the levels of all the speakers. The levels shouls remain consistent enough at all listening levels within a few dbs, so you ears shouldn't hear a difference.

And finally, If you use a 2 channnel amp to power your front speakers, then you won't also be able to power your subwoofer with it. And you can't use a amp to drive a powered sub unless the sub is designed in such a way that the internal amp can be disabled, which isn't all that common.

 

[zumbo]

The sub has to STAY PUT. If you add an amp you will not gain much, if any at all, output at a certain volume. What you will gain is greater control of the speaker with a more acurate sound with greater clarity at high volume levels, given we are speaking of a high quality amp. I added an amp to my Yamaha rx-v1400 and gained a high level of fidelity at high listening levels. Also, I am able to crank just a little higher because the amp remains clean. At low levels, I doubt most people could tell any difference. Myself included. Also, in my case, I am driving 4ohm speakers.

 

[gregz]

Uh-oh, don't you hate when you get five completely different answers to a question?

I echoe Mr. T's question of what specific equipment you have, because that will determine which response is right.

Most HT receivers share one power supply for all output channels, which means when all channels are being driven you could be reaching the current limit of your power supply and hitting the limit - which would compress your peaks and take away the punch.

By using an external amp for the mains, you're dividing the output current of your HT receiver's power supply over fewer channels, which means you're less likely to hit the current limits. This means more dynamic power and overhead - more power to share all around.

But that's only true under the assumptions that a) you're driving full range speakers as surrounds (driving channels full range takes more power), b) your HT receiver is built to give a higher power rating per channel than with all channels driven, c) the amp you choose for your external 2 channel is as good or better than your HT receiver.


As for level matching, you can use a level meter as hopjohn recommends, or you can "wing it" by ear. You set the volume/gain control of the external amp one time, and leave then leave it.

Gotta go with zumbo about the powered sub. If it's a decent powered sub, then its amp is adequate. If it's not a decent powered sub, then using a different amp won't get you anything because the amps are often the best component on powered subs.