Marantz SR7500 and LSi9 speakers.

cd_r

Hi guys!

I'm thinking of purchasing the marantz A/V sr7500 receiver and the pair
LSi9 PolkAudio speakers. However, according to the receiver's specification,
it is able to drive 6to8Ohm speakers and I'm afraid that the LSi9 are
4Ohm speakers. Can anyone tell me if I can damage the receiver
connecting these speakers?

Is it possible to solve this impedance problem biAmplifying the speakers?

Thaks you all!

danger boy

if the Marantz doesn't have enough power. it will likely go into protection mode and shut itself down. it won't hurt the receiver or the speakers. Some times this may only happen when playing music or movies loud.

If i were you.. i'd purchase the 7500 and the LSi9's and hook em up.. and see how things work out before you spend more money on an amp. you can add an exeternal amp later if needed. A external amp will make those 9's sound better though.

McLoki

cd_r wrote:

Hi guys!

Hello and welcome to Club Polk.

I'm thinking of purchasing the marantz A/V sr7500 receiver and the pair LSi9 PolkAudio speakers. However, according to the receiver's specification, it is able to drive 6to8Ohm speakers and I'm afraid that the LSi9 are 4Ohm speakers. Can anyone tell me if I can damage the receiver connecting these speakers?

Running the LSi speakers from a reciever has been gone over many times here. It CAN send your reciever into thermal shutdown (but not likely). It will not sound as good as it should. (it will not live up to its potential)

For most people in the planning stages of purchasing equipment that want to go with the LSi speakers, we would recommend getting separate components or at minimum a reciever with pre-amp outputs and an external amp.

Only you can judge if it is worth the risk to your equipment to settle for less sound quality than you paid for.

Is it possible to solve this impedance problem biAmplifying the speakers?

Nope. - not that easy, but it is only a problem if your amplifier cannot run it.

Once again, welcome.

Michael

cd_r

Thanks you for your replies.

I was thinking in buying this receiver, instead of pre+amp, just because I
wanted to start in the "7.1-world" without investing a lot of money.
However, it is posible, as you said, to use it as a preAmplifier, in the
future, when I could afford buying externals amplifiers using the preouts
conexions.

But until then, I thought of Biamplifying (this receiver can) the speakers in
order to reduce de impedance (driving each way separately). As we know,
all the ways are parallel connectend, so to calculate the speaker
impedance we have to use the next formula:

1/Si = 1/W1 + 1/W2

So, it would be reasonable to think that the individual ways will have a
higher impedance than the sum.

Is it posible? Am I mistaked?

On the other hand, now I'm living in a 12m2 room and I wouldn't probably
have to force so much the amplifier.

What do you think about it?

Thank you.

okiepolkie

Are you saying that you can reroute the rear channels(or side channels) to bi-amp the front channels? If not, then it probably won't work. The reason is that receivers have to sets of binding posts(essentially an A and a B output). These two sets run off of the same internal channel, so it does not change the impedence. You would be bi-wiring, but you would not be bi-amping.

Hope that made sense.

cd_r

Exactly!

This receiver can use the rear channels to drive one way of the main
speakers. Unfortunately, these speakers have 3-ways. Can I biwire two
ways separately from the last one?

Airplay355

The marantz will have enough power to drive the Lsi9's, however if you listen to it loud, there's no way you will be able to crank it. If I were you, I'd get a lesser powered receiver and a seperate amp for the Lsi9's or just go completely seperate and get a pre/pro and a 5 6 or 7 channel amp. Whats your budget?

cd_r

Well, I was thinking to buy the marantz receiver for 700E (about
860 USD), and about 1000E for the speakers, so this is my budget.

howie777

First of all I run "4 ohm" speakers on an Marantz 8200 myself with no issues. I used quotes because if you run my speakers no lower than 80 Hz the least amount of resistance seen by the receiver is only 6 ohms. I'm not sure what the curve looks like for LSis but I think you will be fine running LSis on Marantz gear especially if you have setup as small on your receiver and use a sub.

I hope that helps, and I have had this setup for about 3 years now with no issues.

I talked to a guy at Marantz who confirmed that my 8200 will have no issues with 4 ohm speakers too. So I doubt you will see any issues.

Howie

aaharvel

The 7500 can take those lsi9's. Marantz has very high quality amp sections with good current- even better than Denon imo. You can always upgrade to a separate amp. later. That's one nice receiver.