Which receiver (Pioneer or Yamaha) for LSi-15

brentba

Hi everyone (my first post to this forum),

I decided to take advantage of Polk's ebay store deal and purchase a pair of refurbished LSi-15's. Wasn't really in the market for new speakers right now, but I've always enjoyed the LSi series so I decided it was hard to pass them up at $850/pair.

Initially, I am planning on using one of two receivers that I currently own (will eventually upgrade to a separate amp, but not a priority for me right now). I realize that neither of them is ideal, but which of the following do you think would be better suited to power the LSi-15s at modest listening levels (both for 2 channel and 5.1 applications -- other speakers in 5.1 setup are 8 ohms and lesser power requirements than the LSi). My options are as follows (again, I already own both receivers):

OPTION 1: Yamaha RX-V867 (7.1 channel receiver)
Discrete 7 channel amp
Rated Output Power (20Hz-20kHz, 2ch driven): 95W (8ohms, 0.09% THD)
Dynamic Power per Channel (8/6/4/2 ohms): 130/165/195/240W

Can reportedly handle 4 ohm loads for front L/R speakers

Front L/R channels can be "biamped" by utilizing back surround/presence channels

OPTION 2: Pioneer VSX-D912 6.1 channel receiver (approximately 10 years old)
Continuous power output (stereo)
Front: 110 W per channel (20?20,000 Hz, THD 0.2 %, 8 Ω)

Continuous power output (surround)
Front: 110 W per channel (1kHz, 1.0 %, 8 Ω)
Center: 110 W (1kHz, 1.0 %, 8 Ω)
Surround: 110 W per channel (1kHz, 1.0 %, 8 Ω)
Surround Back: 110 W per channel (1kHz, 1.0 %, 8 Ω)


If I use the Yamaha, would it be beneficial to bi-amp the LSi-15's, or does this generally provide little benefit? I'm not sure how the power is divided in the LSi-15's when bi-amped.

Any input will be appreciated.

Thanks!

skrol

Welcome to the forums. Does either have pre-amp outputs? I recommend an external amp to drive the LSi15's.

brentba

skrol wrote: »

Welcome to the forums. Does either have pre-amp outputs? I recommend an external amp to drive the LSi15's.

Both have pre-amp outputs, but as I mentioned above, I will be using one of the two available receivers for now until I decide to purchase an external amp in the future. I understand that an external amp is the best/most appropriate option.

Thanks for your reply.

B Run

To be completely honest neither one will come close to powering those Lsi's, or live up to their advertised wattage. I'd pick the Yamaha out of those two but be careful and definitely keep the volume down until you can pick up that amp. Congrats on the new speakers and welcome!

chumlie

B Run wrote: »

To be completely honest neither one will come close to powering those Lsi's, or live up to their advertised wattage. I'd pick the Yamaha out of those two but be careful and definitely keep the volume down until you can pick up that amp. Congrats on the new speakers and welcome!

Good advise.

brentba

Thanks for the replies.

Any suggestions for an external amp that will provide sufficient, clean power without costing more than the speakers themselves?

Brent

chumlie

Used Parasound HCA1500a runs about $400. Plenty of other options used.

B Run

Absolutely, there's lots of options. You'll get the best bang for your buck going used for sure, so i'd check Audiogon, Ebay or your local Craigslist. I'd look for Adcom, Rotel, Parasound, Carver, Outlaw, Nad or B&K. You hit the nail on the head with CLEAN power, high current is just as important as stated wpc.

brentba

I'll definitely keep an eye out for a good deal on a used amp. Thanks for the recommendations!

In the meantime, will I derive much benefit using the bi-amp feature on the Yamaha receiver or could this actually be detrimental in some way?

Brent

mole'

emo amps can be found used for a great price. they sound good with the LSi speakers too

nguyendot

Please search the forums on biamping. There are MANY options on this. Also, search for powering LSI speakers, I wrote a quite detailed post about what you need to power them, and why using a receiver only (especially a cheap one) is asking for your own personal forest fire.

tonyb

brentba wrote: »

I'll definitely keep an eye out for a good deal on a used amp. Thanks for the recommendations!

In the meantime, will I derive much benefit using the bi-amp feature on the Yamaha receiver or could this actually be detrimental in some way?

Brent

Yes it can be, you could do damage to the speakers or receiver or both. Keep the volume down until you can add an amp and you should be ok.

brentba

nguyendot wrote: »

Please search the forums on biamping. There are MANY options on this. Also, search for powering LSI speakers, I wrote a quite detailed post about what you need to power them, and why using a receiver only (especially a cheap one) is asking for your own personal forest fire.

Fire? That would be bad. Do you have any personal or second-hand combustible amplifier stories that you could share? I'd be interested in hearing one.

Don't most amps have circuitry that prevents overheating to the point of catching on fire?

And can you please define "cheap" receiver?

...you could do damage to the speakers or receiver or both. Keep the volume down until you can add an amp and you should be ok.

I would imagine that one would have to play the speakers at fairly high levels for an extended period of time to risk real damage. No?


Thanks...

cfrizz

You don't understand that 4ohms speakers demand A LOT of power, asking a receiver to drive them unless at relatively low volume is going to make just about any receiver including yours work twice as hard to put out sound. It won't really sound good and you will be tempted to turn the volume up to make it sound good which will put even more stress on the receiver.

It may go into protect mode, hopefully before you fry either your receiver or the speakers. Biamping is just plain suicide. All you're asking is for the already over stressed receiver to work three times as hard with no benefit.

My brother originally had a 50wpc Rotel amp driving his LSI 7s, by the time we got through listening to a movie, you could fry an egg on top of the amp! You'll be lucky if you even manage to get 50wpc out of the receiver and it will be less with more than 2 channels going.

You bought some great speakers, but it is going to cost more money to safely get the best out of them. Please excercise caution, and make getting a separate amp of at least 200wpc @ 8ohms a priority.

PSOVLSK

I'd use the Yamaha and not bi-amp. Keep the volume low as you said you planned to do and I think you'll be ok. I've got a Rotel amp for sale that would be a cheap starting point until you get something better. Plus, you should be able to flip it for no loss when you're ready to upgrade. http://www.polkaudio.com/forums/showthread.php?134124-Housecleaning-LSI9-s-NHT-2B-Parasound-Monster

Sorry for the shameless suggestion, but I truly feel the amp would be good for you or I wouldn't have mentioned it.

brentba

Thanks everyone for the excellent information. Perhaps I will hold off on powering up the Polks until I purchase a separate amplifier, lest I risk damaging the speakers and/or receiver.

Can anyone point to an article that explains, in technical terms, the interaction between an amplifier and a speaker and how exactly one or the other can be damaged when the amp is underpowered. I assume V=IR (Ohm's Law) is at the root of the explanation, but I'm no electrical engineer so I can't figure it out on my own.

Thanks

brentba

One more question. The manual for my Yamaha receiver indicates the following:

This unit is configured for 8 Ω speakers at factory setting. When connecting to 6 Ω speakers, carry out the following procedure to switch to 6 Ω

Note: When this unit is configured for 6 Ω Speakers, 4 Ω speakers can also be used as the front speakers only.

And this:

Yamaha receivers have a built in computerized protection circuit, which will activate in certain over-current conditions. This means that the unit is drawing too much current through the amplifier or power supply, and the built in computer turns the receiver off. This is designed to protect your receiver and speaker systems. There can be several different reasons that the receiver will shut off prematurely.

Again, I completely understand that sound quality will be less than optimal with an A/V receiver, but given the above information, it seems unlikely that any damage to the speakers or receiver would occur at modest listening levels.

Is this just deceptive "advertising" from Yamaha?

I completely agree that an external amplifier is ideal but I still would like to understand exactly why I am risking damage to the speakers/rreceiver with LSi/RX-V867 combination.

I did search this forum for answers to these questions, but did not come up with anything specific. Mostly just the same response over and over -- "get an external amp or you will damage your speakers/receiver" but no satisfying explanations as to why damage is a real world concern at modest listening levels nor any actual accounts of this actually happening to anyone.

I hope I'm not being annoying.

Educate me

PSOVLSK

My personal opinion is that you'll be okay with the Yamaha as long as you listen at modest levels.

You understand that you need an amp for them to sound their best and you understand that you can't drive them hard with the AVR. Hopefully you have an idea how hot or cool the Yamaha runs now during normal listening. If it runs a lot hotter than normal with the 15's I'd be a little concerned, otherwise I wouldn't worry about it too much. Not saying it has to get hot to ruin something, but I think that's a good indicator that's easy to monitor.

I'd still love to sell you the Rotel though:eek::cheesygrin:

ravaneli

brentba,

your yamaha receiver will have NO PROBLEMS powering the LSi as long as you follow the manufacturer instructions. Also I recommend biamping if listening in 2.0. It helps. In no situation does biamping have a negative effect.

I will warn you that there is some serious confusion around here about what power handling means. Yes, amp will be better, but don't push the volume too high and you will be fine.

here is the best power per $ amp out there. Great reviews from amateurs, very good on the benchtests too. The distortion levels are not audible. 180W @ 4 ohm on the bench.

There are more powerful amps out there with even lower distortion but for 200 bucks that thing is a miracle.

http://www.amazon.com/Behringer-A500-Reference-Amplifier/dp/B000CZ0RL0

oh yeah, forgot to mention I tested it myself too!

hertz9753

ravaneli wrote: »

brentba,

your yamaha receiver will have NO PROBLEMS powering the LSi as long as you follow the manufacturer instructions. Also I recommend biamping if listening in 2.0. It helps. In no situation does biamping have a negative effect.

I will warn you that there is some serious confusion around here about what power handling means. Yes, amp will be better, but don't push the volume too high and you will be fine.

here is the best power per $ amp out there. Great reviews from amateurs, very good on the benchtests too. The distortion levels are not audible. 180W @ 4 ohm on the bench.

There are more powerful amps out there with even lower distortion but for 200 bucks that thing is a miracle.

http://www.amazon.com/Behringer-A500-Reference-Amplifier/dp/B000CZ0RL0

oh yeah, forgot to mention I tested it myself too!

What happens when Bi-amp a 4ohm Speaker with receiver?

nguyendot

ravaneli wrote: »

brentba,

your yamaha receiver will have NO PROBLEMS powering the LSi as long as you follow the manufacturer instructions. Also I recommend biamping if listening in 2.0. It helps. In no situation does biamping have a negative effect.

I will warn you that there is some serious confusion around here about what power handling means. Yes, amp will be better, but don't push the volume too high and you will be fine.

here is the best power per $ amp out there. Great reviews from amateurs, very good on the benchtests too. The distortion levels are not audible. 180W @ 4 ohm on the bench.

There are more powerful amps out there with even lower distortion but for 200 bucks that thing is a miracle.

http://www.amazon.com/Behringer-A500-Reference-Amplifier/dp/B000CZ0RL0

oh yeah, forgot to mention I tested it myself too!

Waste of time. Using that receiver is going to severely limit the capabilities of those speakers, which is a problem.

pyrocyborg

cfrizz wrote: »

My brother originally had a 50wpc Rotel amp driving his LSI 7s, by the time we got through listening to a movie, you could fry an egg on top of the amp! You'll be lucky if you even manage to get 50wpc out of the receiver and it will be less with more than 2 channels going.

A lot of amps will be "warm" or hot even when powering 8 ohms speakers at low level. My 50w NAD do the job quite well, and it's as "hot" as when I was driving my RTiA3 off it, or any other 8 ohm speakers friends brought home. What about all the 20w tube amps here and there driving big boxes? Most of the time, except if you drive the 7s to 100dB, you won't use more than 20w. Anyways, the 15 aren't the 7, so it's another story and those 15s require tremendous and stable power to sound great.

To OP, I wouldn't mix impedance on the same receiver (e.g. using 4 ohm front speakers and 8 ohm rear) for personnal reasons, but well... Keep it low until you get a dedicated amp: I mean, these are tower speakers, they require power (and even bookshelf love power).

sponger

I've spent a lot of time drooling over those refurbished LSi towers on ebay too. I hope they work out for you, but the warnings in many of these comments are precisely why I've learned to just put the idea behind me. I recall from my days when I would toil with car audio stuff that properly powered modestly priced speakers will sound better than hungry, underfed premium speakers. Still, if you manage to make it happen then that would be great news.

F1nut

brentba,

your yamaha receiver will have NO PROBLEMS powering the LSi as long as you follow the manufacturer instructions. Also I recommend biamping if listening in 2.0. It helps. In no situation does biamping have a negative effect.

I will warn you that there is some serious confusion around here about what power handling means. Yes, amp will be better, but don't push the volume too high and you will be fine.

here is the best power per $ amp out there. Great reviews from amateurs, very good on the benchtests too. The distortion levels are not audible. 180W @ 4 ohm on the bench.

There are more powerful amps out there with even lower distortion but for 200 bucks that thing is a miracle.

http://www.amazon.com/Behringer-A500.../dp/B000CZ0RL0

Horrible advice. brentba, please ignore all of it.

ravaneli

hertz9753 wrote: »

What happens when Bi-amp a 4ohm Speaker with receiver?

nothing. What do you think could happen? A violent explosion?

lower resistance increases the current. but that doesn't automatically mean something will explode. as long as you stay under the power handling of the avr everything is operating normally. normally, normally.

B Run

When I posted in this thread I was hoping Ravaneli wouldn't butt in and spout of his usual repetitive BS about pro amps, or distortion. In all seriousness you give the worst advice i've ever read on this forum.

brentba

Here's a thought:

I would assume that Polk has sold thousands of LSi series speakers over the past ten years, mostly from big box chain stores (?). I would also assume that at least 50% of the big box store customers were not informed that they could not adequately power the LSi speakers with an A/V receiver. In fact, many of them were probably sold an A/V receiver specifically for the purposes of powering a pair of LSi's.

If my assumptions are at all even close to being accurate, then I would assume it would be very easy to find numerous accounts of damaged LSi speakers and A/V receivers all over the internet.

Yet, I have not found any such accounts. I have however, found plenty of accounts of people using A/V receivers to power the LSi's without any resulting damage. Poor performance, well, probably. But that is subjective and most people who rely on big box stores for A/V advice probably don't know the difference between good and bad speaker performance anyhow.

So, can someone please give me a real world example that supports what seems to be the conventional wisdom on this board (i.e. A/V receivers kill LSi speakers).

And, please, no more comments on inferior performance of the LSi with an A/V receiver vs. external amp. No one is debating that issue here. We all seem to be on the same page about that.

Thanks.

Brent

11tsteve

its not that it will kill anything, its that it could kill something. it is not controversial, it is conventional wisdom... that when you overload an amp, it will overheat. and that if you try and drive a speaker like the LSi with an underpowered amp, and try to acheive loud volume levels you risk clipping the amp and most like killing your tweeters.
its not that you shouldn't use your AVR, but you need to exercise caution.

EndersShadow

sponger wrote: »

I've spent a lot of time drooling over those refurbished LSi towers on ebay too. I hope they work out for you, but the warnings in many of these comments are precisely why I've learned to just put the idea behind me. I recall from my days when I would toil with car audio stuff that properly powered modestly priced speakers will sound better than hungry, underfed premium speakers. Still, if you manage to make it happen then that would be great news.

Sponger I like you . You hit the nail right on the head.

Just some food for thought. If you look at most Big Box Stores and the speakers they carry, do you notice that most of them tend to be 8 ohm? There is a reason for that. The 8 ohm speakers will never have a problem with avr's on the market today. Thats why Polk has the RTi line. The name of the line even stands for Reference Theater something something lol.... Its a speaker built to be used for mostly Home Theater driven by a receiver. Its also IMHO why the new LSiM's are 8 ohm loads as well.

Most Big Box stores did not carry the LSi series due to it being 4 ohm and expensive to boot. I dont actually even know of a store still carrying 4 ohm speakers to date in my area (Best Buy, HH Gregg, etc). This includes the specialty stores in my area that have 2k+ speakers. We have a Fry's and they have the LSi speakers but they are selling out of them and not getting more obviously. Thats the only Big Box or specialty instal store within like 300 miles that has them and even they they are in their dedicated HT room most folks never go into.

brentba

Most Big Box stores did not carry the LSi series due to it being 4 ohm and expensive to boot. I dont actually even know of a store still carrying 4 ohm speakers to date in my area (Best Buy, HH Gregg, etc). This includes the specialty stores in my area that have 2k+ speakers. We have a Fry's and they have the LSi speakers but they are selling out of them and not getting more obviously. Thats the only Big Box or specialty instal store within like 300 miles that has them and even they they are in their dedicated HT room most folks never go into.

The Magnolia Home Theater section of Best Buy carried the LSi line. In fact, that's the only place I've ever had the chance to hear them.

That wasn't even the most expensive speaker they were carrying at the time. They also had a couple Martin Logan electrostatic panels from the lower end of the Martin Logan line (which I believe they still carry).

EndersShadow

brentba wrote: »

Best Buy carried the LSi line. In fact, that's the only place I've ever had the chance to hear them.

Interesting, they never carried them here in Indiana or the Midwest from what I ever saw. Must be a regional thing.