Do I *need* an amp?

polkieintx

New to Polk and the forum. Couldn't find an answer by searching old posts, so apologies if this has been asked before:

I have a pair of RTi12 fronts, pair of RTi10 sorrounds and a PSW110 sub making up a 4.1 setup (waiting on a good deal for a center speaker). I have them driven by the Onkyo 805, which is rated at 130W/channel at 8ohms. My question is: do I *need* to drive these speakers with an external amp with a higher power? I'm on a tight budget and like the sound from the Onkyo by itself, so I only want to spend on an amp if my current setup isn't recommended for the speakers (meaning, will the onkyo damage them at some point due to lack of power)?

If I do need an external amp, how much power should I be looking for? My typical usage is 50-50 movies and music, if that helps.
TIA.

venomclan

Keep what you have. Your speakers are 8 ohms and will be fine with the 805 unless you blast them to insane levels.
Venom

crd2002

if you are happy with the sound then dont bother if you want to blast them like I do then you will need a amp

seeclear

+1 to both replies

polkieintx

Thanks for the replies, guys. Exactly what I wanted to hear
I don't crank up the volume too much, so I guess I will hold off from buying an amp.

ShinAce

Lack of power will not damage speakers. Cranking the volume to the point that the signal starts clipping(this makes the music harsh) can blow your tweeters. You would need to have a party full of drunk people to achieve that.

cfrizz

Welcome PolkieinTX! As others have said, you can keep what you have especially since you are happy with the sound.

Just know that it can sound even better with separate amplification & since you already have a receiver that has preouts you are all set when/if you do decide to go in that direction.

AdamRagland

+1 on cfrizz....i was happy with my rti70's and the denon 3803..that was untill i heard what a seperate amp did for my mains. ESPECIALLY listening at lower levels.

[Deleted User]

I believe the question on the onkyo 805 was asked on another thread.. very recently... Are you the same person?

kuntasensei

To the OP: If you feel that you don't have enough power going to your RTi12s, you can shift some of the load to the subwoofer. The Onkyo 805 lets you set independant crossovers for each channel down to 40Hz, meaning you can shift some of the low end off to your subwoofer so that its amp handles that load, freeing up more headroom from the receiver. If you set your speakers to about 50Hz, that should be well below the point of directionality, should give you a good transition to the sub before the speaker's -3dB point (especially if you've run Audyssey and let it do its room correction), and should give you a little more breathing room as far as the amp section on the 805.

Not saying that you NEED to do this necessarily, since the 805 should be more than adequate. Just saying it's an option that might help a little if you find any harshness in the highs or muddying of the bass at higher playback levels.

rainman31

halenhoang wrote: »

I believe the question on the onkyo 805 was asked on another thread.. very recently... Are you the same person?

The guy only has 2 posts and they are in this thread

cfrizz

Welcome to Club Polk Rainman.

polkieintx

Ace, like I said I dont crank it up too much. Mostly stay within the -20 to -30db levels on the receiver. So I guess you agree with the previous posters that I dont need an amp right away.
Cfrizz, Adam, glad that I have a path to upgrade my system...if and when the dough starts flowing.
halenhoang, not sure which thread you are referring to but like rainman has pointed out this thread has all of my posts so far on this forum. So, no, I'm not that person.
kuntasensei, I have the crossover on the fronts set to 80Hz (the default on the receiver), so I guess I'm already sending more of the power-hungry frequencies to the sub. I'm yet to run Audyssey, I will try it out shortly.

Thanks again for all the suggestions.

edossin4

halenhoang wrote: »

I believe the question on the onkyo 805 was asked on another thread.. very recently... Are you the same person?

That may have been me. I decided to get an external amp. An Adcom gfa555 (200 watts) from ebay for $378 (including shipping). It really makes a difference. It sounds fantastic.

cfrizz

Great score Edossin4. Welcome to Club Polk!

Sherardp

The amp will wake those 12s up for sure. I started out just using my AVR, although it was capable, the amps gave me a more refined, detailed sound. Try one out when you can, check out Audiogon and pull the trigger when youre ready to venture out into seperates.

rainman31

cfrizz wrote: »

Welcome to Club Polk Rainman.

Thanks for the welcome. I am glad to be a part of this forum.

ShinAce

Your setup looks good to me. It is clean, simple, and very effective.

[Deleted User]

Rainman, you are correct, only 2 posts. However, I guess by sheer coincidence, the onkyo 805 is suddenly taking the market by storm. There are several other names, created in jan 08, all asking about the onkyo 805. hmmmmm!!!

DeusExa

we love the 805!

kuntasensei

polkieintx wrote: »

kuntasensei, I have the crossover on the fronts set to 80Hz (the default on the receiver), so I guess I'm already sending more of the power-hungry frequencies to the sub. I'm yet to run Audyssey, I will try it out shortly.

Oh, lord... you're running them at 80Hz? If you think your system sounds good now, wait until you run Audyssey! After you do, dial the crossovers back to around 50Hz, because the Onkyos detect anything that goes lower than 80Hz as "full range".

Be sure to run the full 8 positions of Audyssey, using a tripod (~$20 at any camera store - AN ABSOLUTE NECESSITY FOR RUNNING AUDYSSEY) with the mic sitting just above any headrests your seating has (to prevent reflections from the headrests that may alter response). Position 1 should be your main central position (i.e. in line with the center channel or mid-point between left and right). 2 should be at least 3 feet to your right when facing the screen. 3 should be 3 feet to left of center. 4-6 should mirror those positions, but about 2 feet further in front of you (to give it an idea of bass response further into the room). Positions 7 and 8, you can do somewhere in between all that. I did this pattern:
6X4X5 <-- ~1ft from front of couch
X7X8X <-- Front edge of couch
3X1X2 <-- Couch

This should give Audyssey a good sense of your room's effect on the sound and give it a far better equalization that will really bring your Polks to life. Manual equalization only gives you about 7 bands of parametric EQ, whereas Audyssey can do hundreds of adjustments PER CHANNEL in the time domain.

If you need any more info, check my Audyssey setup of the 705 FAQ over at AVSForum here.