Lsi15 - Best way to drive them...

Racker99

In a recent reply I gave the story, but basically I was able to pick up a pair of brand new LSi15's in Cherry for around $660.

Now, before I hook them up in my theater room as the new left & right channels, I would like to know that my tuner will not cause harm to them by trying to run them with it.

I currently have a lower end Sherwood A/V receiver RD-7502. http://www.sherwoodusa.com/prod_rd7502.html Specs wise it indicates 100 Watts per Channel at 8 Ohms. Longer term I'm not opposed to upgrading this to a higher quality receiver, but am overall pretty happy with how it's working currently. Upstairs I currently have one of these receivers driving a pair of RTi8's and they sound great.

I realize that the LSi15's are 4 Ohm speakers, but don't know technically if they will still work with my current receiver, but not optimally, or by trying to drive them with this unit I will actually damage them in some way.

If I do need another amp, what is the cheapest 2 channel amp that will provide reasonable sound that might work?

dorokusai

You can certainly run them but I would stick with moderate listening levels and monitor the heat on the Sherwood. A seperate amplifier would be a huge benefit. Check out the Flea Market section for some options.

Face

The "Analog Output", are those considered pre-amps?

Refefer

They will technically work, but be prepared to not be impressed. The Lsi series loves power and needs to have an amp that can handle the impedance dips.

Get yourself a used carver or adcom amp for around $250, and you should be good. Try to get at least 150 clean watts into them, and more if possible.

Racker99

Given that the speakers are rated upto 250 watts / channel, will I be happy with an Amp that delivers 150 watts, or should I try to get something that does a full 250?

I know that the watts alone don't mean better sound, but I've not dealt with power hungry speakers before.

Also since the rest of my speakers will still be running at 100 watts / channel I don't want to make things sound unbalanced. Would that be an issue if I used 250 watts vs. 150?

Refefer

Racker99 wrote: »

Given that the speakers are rated upto 250 watts / channel, will I be happy with an Amp that delivers 150 watts, or should I try to get something that does a full 250?

I know that the watts alone don't mean better sound, but I've not dealt with power hungry speakers before.

Also since the rest of my speakers will still be running at 100 watts / channel I don't want to make things sound unbalanced. Would that be an issue if I used 250 watts vs. 150?

It depends on how loud you play it. If you're going to play it at very loud levels, you don't want to risk overdriving the amp and possibly blowing everything.

How big a room do you have? Will this be for home theater or just a damn good 2 channel? Honestly, 150 quality wpc from a high current amp should do most people just fine, so long as your not trying to set a sound level record.

That said, you can never have too much juice on reserve: just asking for too much when you don't have it, or giving too much past its rating.

Racker99

I'm planning to put the LSi15's into my theater room as my Left and Right Channels.

Currently I have a Polk CS400 as my center and am using TC615's as my surround speakers. I also have a Sunfire 700 Sub.

The room size is 14' x 23', so it's a pretty large theater room space. I'm using a Panasonic 100U projector with a 139" diagonal 16:9 screen.

hockeyboy

You will never regret getting a more powerful amp. If you are going to spend the money just go a bit more and get something that will last you for a decade. My amp puts out 400 WPC at 4ohms and has never given me problems with too much power.

Remember to get an amp that is actually rated at 4 ohms though. The majority of amps that say 100 watts are talking about at 8 ohms. If that same amp is also rated at 4 ohms it will push closer to 200.

Racker99

I had had tried to check with Mark and local to see if I could find an Amp for a good deal - No word back from anyone so I was looking on sleazbay a bit.

There was a Carver TFM-25 that was ending its auction today, I believe it was put up by a refurb shop so it should be in good working order. Could have gotten it for $350 or so, but they set a reserve at $395 so I had to bid up to hit the reserve. Final Cost is $395 + around $62 in shipping.

Given that I was willing to pay up to around $400 locally with no shipping I don't feel like I got THAT bad of a deal. Hopefully no more than $100 over what it should have cost.

Given that it'll deliver 350 Watts RMS per channel at 4 ohms I hope it'll drive my new LSi15's sufficiently, (but not over drive them.)

Thoughts?

MikeCamp

www.emotiva.com

XPA-5

bbeacham

Racker99 wrote: »

Given that it'll deliver 350 Watts RMS per channel at 4 ohms I hope it'll drive my new LSi15's sufficiently, (but not over drive them.)

I have a Sunfire TGA-5400, which does 800W x 5 @ 4 ohm driving 4 LSi15s and an LSiC. So far all it has done is make the sound crystal clear and unstrained at the highest sound levels. More than once I have read that speakers are more easily damaged by clipping from an underpowered amp than from having to much power. Of course, as with anything I am sure there are instances where you can fry a speaker with to much power.

However, even when I was driving these speakers with a Denon 3805 receiver (120w/ch), and, later, a Sony 7100ES receiver (175w/ch) they produced high sound levels and great sound. Its just that now they produce even better sound.

ohskigod

that Carver should do those 15's nicey nice. the sound difference between that and your sherwood is going to shock you a bit.

Racker99

I haven't received the Carver Amp yet, but I did finally receive my second speaker yesterday. I hooked the pair up to the Sherwood and was already amazed at how clear and nice they sounded. After a few songs however the speakers didn't quite sound as clear and I believe my Sherwood was starting to under drive them, so I turned everything off before any harm could occur.

In looking at how to hook up my new amp when it arrives I was shocked to discover that the Sherwood receiver I purchased doesn't have Pre-outs for all channels. It only has a single pre-out for the subwoofer. However, it does have 'tape out'. My theory is that I can run the 'tape out' signal to the amp and all should be well with the world. For stereo music I'm 99.9% certain that this will work just fine. My concern exists for when I am watching a movie in 5.1 or 7.1 surround sound.

Does anyone know or have any guess as to if the tape out stereo feed will be equivalent to what pre-outs for Left / Right channel would provide? Or will they be getting more of the signal than they should and end up providing an incorrect 5.1 / 7.1 listening experience?

If I have to purchase a new A/V receiver which actually has pre-outs, I'll consider it, but I'm hoping I can correctly drive these new speakers without having to completely replace my whole home theater setup.

tcrossma

I could be wrong, but isn't a tape output a fixed-volume output?

Face

tcrossma wrote: »

I could be wrong, but isn't a tape output a fixed-volume output?

You're correct.

Racker99

Yes, it's like a line-out level. I expect that I'll have to adjust the volume level for the Left / Right channel on the amp separately from the receiver.

Ron Temple

Go back to ebay and bid on a Harman Direct 2xx or 3xx series AVR that has pre-outs. Should be able to stay around $200. It's the cheapest way I know of to get a nice sounding pre for your TFM25.

Lowell_M

Ron Temple wrote: »

Go back to ebay and bid on a Harman Direct 2xx or 3xx series AVR that has pre-outs. Should be able to stay around $200. It's the cheapest way I know of to get a nice sounding pre for your TFM25.

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