Quick question on speaker impedance...

Pepsiaddict

Hi all, I'd just like to first off say hi! First post and first time owner of Polk



Now, I just picked up some RTiA7's, a pair of them because of a sale I couldn't resist. They came with the PSW10 sub also.


Now my question is this, I don't have the funds to buy the receiver I want just yet, (Denon 991), That will be next month. But I have these awesome speakers sitting here and have my old mini system which is a Phillips FW-C577-37. I will post technical info from the manual :

AMPLIFIER
Output power 330 W total power
2 x 165 W RMS(1)
2 x 135 W FTC(1)
Signal-to-noise ratio ≥ 75 dBA (IEC)
Frequency response 50 – 18000 Hz, –3 dB
Input sensitivity
AUX In 640 m V
Gameport 310 mV
Output
Speakers ≥ 6 Ω
Headphones 32 Ω – 1000 Ω
(1) (6 Ω, 60 Hz – 12.5 kHz, 10% THD)



Now, my question is this, I know the RTiA7's are 8Ω...but I'm wondering if I can use the mini system to run the speakers for the next month or so until I get my receiver without hurting the speakers. I really couldn't care less about the mini system, I just don't want to hurt these lively speakers with the wrong impedance. I have done some google'ing and really don't understand it all lol, was really hoping someone here could help me out


Thanks for your time

grimmace19

I can't imagine it being a good idea to try and run those speakers from the mini system. Though it boasts 165 watts I HIGHLY doubt it comes anywhere close to that. Just be patient rather than risk it.

Pepsiaddict

Thanks for the quick reply. The mini system is definitely pushing some good power, even with just the 2 small speakers it came with I rattle things off the walls and get in trouble with the roommates

On the subject tho, why do you say that? Just looking for some insight into what could possibly happen and to what, so on and so forth

Pepsiaddict

From what I can gather from Google, higher impedance ratings require less power from the amp, so an amp that is using 6 ohms should be fine with 8ohm speakers, just not lower than 6, or else the amp could burn out from trying to push too much power...

Also, you talk about wattage, that from what I have read really doesn't have any impact on it, plus on the Polk spec page it says Recommended Amplifier Power : 20-300 w/channel





But again, I could not be fully understanding it


Edit : I also know that I am not going to be getting even close to what these speakers can produce, I just want to be able to use them without hurting them until I get my receiver

grimmace19

I'm just concerned that you will underpower the speakers with that thing. You gotta think that the a7's are a much much bigger speaker than the bookshelves that come along with it thus making it hard to drive. I don't think the impedance will be an issue for you but by not giving those speakers enough clean power they will ultimately distort and possibly get ruined. The speakers will draw the power they need from your source and if it can't handle it it's got bad news written all over it.

Pepsiaddict

But from what I've been reading, under powering only hurts speakers when the amp is pushed past it's limits and when you get distortion, (as you said) but if I don't have any distortion one would assume it's safe =/

zarrdoss

You could power them with that for now but at LOW levels. those crappy little systems power in not the best or cleanest. And grimmace19 is correct it will not handle these speakers at high volume and they will probably get damaged. I would put my 60wpc sonance amp up against that any day. Its kind of like hp and torque you need to have both for control same thing for powering speakers such as these you need power and current, and those little systems just don't have the current.

tonyb

You'd be better served picking up an old receiver off of craigslist for 50 bucks than running them off that mini system. You could re-sell that old receiver when you get the one you want, at minimal to no loss.

fatpiggy

I wouldnt use the mini amp.Worse thing for Polk speakers is to drive them underpowered, you can burn out voice coils if the amp clips.Wait till you get the right amp, drivers are expensive I know I have just had to fork out a complete new set of drivers for someone trying to drive these polk with the wrong amp and not knowing what they were doingMy 2 cents

Fat piggy.

PSOVLSK

tonyb wrote: »

You'd be better served picking up an old receiver off of craigslist for 50 bucks than running them off that mini system. You could re-sell that old receiver when you get the one you want, at minimal to no loss.

Good idea.

messiah

Pepsiaddict wrote: »

Hi all, I'd just like to first off say hi! First post and first time owner of Polk



Now, I just picked up some RTiA7's, a pair of them because of a sale I couldn't resist. They came with the PSW10 sub also.


Now my question is this, I don't have the funds to buy the receiver I want just yet, (Denon 991), That will be next month. But I have these awesome speakers sitting here and have my old mini system which is a Phillips FW-C577-37. I will post technical info from the manual :

AMPLIFIER
Output power 330 W total power
2 x 165 W RMS(1)
2 x 135 W FTC(1)
Signal-to-noise ratio ≥ 75 dBA (IEC)
Frequency response 50 – 18000 Hz, –3 dB
Input sensitivity
AUX In 640 m V
Gameport 310 mV
Output
Speakers ≥ 6 Ω
Headphones 32 Ω – 1000 Ω
(1) (6 Ω, 60 Hz – 12.5 kHz, 10% THD)



Now, my question is this, I know the RTiA7's are 8Ω...but I'm wondering if I can use the mini system to run the speakers for the next month or so until I get my receiver without hurting the speakers. I really couldn't care less about the mini system, I just don't want to hurt these lively speakers with the wrong impedance. I have done some google'ing and really don't understand it all lol, was really hoping someone here could help me out


Thanks for your time

Those might actually be the worst specs I've ever seen!! :eek:

10% THD :eek:
75db SNR :eek:
FR 50-18000 hz :eek:

I'd eat my own poo if it actually puts out 165 watts a channel, and that ain't gonna happen

TECHNOKID

Now, my question is this, I know the RTiA7's are 8Ω...but I'm wondering if I can use the mini system to run the speakers for the next month or so until I get my receiver without hurting the speakers. I really couldn't care less about the mini system, I just don't want to hurt these lively speakers with the wrong impedance. I have done some google'ing and really don't understand it all lol, was really hoping someone here could help me out

Just be patient and wait till you get the proper amp. This si way too risky to damage your speakers not counting you will not be able to really enjoy what they are capabable of. Keep in mind, garbage in = garbage out, you could have 1000$ speakers but if driven with with poor input you won't enjoy.

BTW; welcome to CP

ecod123

messiah wrote: »

Those might actually be the worst specs I've ever seen!! :eek:

10% THD :eek:
75db SNR :eek:
FR 50-18000 hz :eek:

I'd eat my own poo if it actually puts out 165 watts a channel, and that ain't gonna happen

+1 on the specs part and ROFL on the poo part!

ecod123

tonyb wrote: »

You'd be better served picking up an old receiver off of craigslist for 50 bucks than running them off that mini system. You could re-sell that old receiver when you get the one you want, at minimal to no loss.

Agree with tonyb. Not sure where you are at, but in most big market craigslist, lots of older but perfectly usable receivers going for great prices. Those receivers will drive your speakers way better and you will derive great enjoyment from your speakers too.