LSi 15's Not putting out bass.

jomat77

Hi folks, very new to the stereo equipment scene and I have a few questions about a system I just picked up.
HK AVR7300
Polk LSi 15's
Polk LSi C
Polk DSW Pro 400

Very happy with the system so far but have a few questions.
1. Why am I not getting punchy midrange bass out of the 15's. The woofers seem to be working but they just don't put out much bass. My DSW sub works fine, but I do notice a hum if the sub volume is turned up to loud. Otherwise all of the speakers sound great...even when turned up pretty loud. Any suggestions on how to get more punch out of those woofers in the towers?
2. I want to get more speakers to add to the surround sound. I want to stick with this same series. Should I get the 7's, F/X's, or both? My room is 12x20.
3. If I need a separate amp for the woofers on the towers...which one would you suggest. Would like to stick with HK components but open to all suggestions. $500 or less (used)
4. Finally, I read somewhere about reversing the polarity? of the woofers on the 15's and this supposedly gets more out of them. Just wondering if anyone heard of this before. I'm not messing with that stuff, just wanted to see if there's anything to that.

Thank you in advance for any help and suggestions.

Legender

I would suspect most here would tell you that you're under powering them with your 110 watts per channel at 8 ohm, or 125 with only 2 channels AVR. The LSi15s are 4 ohm speakers and you keep turning them up loud you're bound to break something....
You need to get an amp between the AVR and the speakers that will drive 4 ohms powerfully.
You need a separate amp for the speakers period.

You will be much happier with the system once they are fed the proper power.

jomat77

Okay, I was prepared for that scenario so I appreciate that feedback. That said, are there any amps you suggest? Also, I'm a novice here so bare with me but...on the terminals of my 15's there are gold plates that span the upper and lower terminals. I only have one set of wires going to both towers and they are connected to the "front" channels on my receiver. Should they be hooked up differently. Sorry for the novice question but again...very new to all of this stuff.

F1nut

Your AVR is not rated to drive 4 ohm loads, your speakers. Do NOT turn the volume up as you will cook the AVR and likely damage the speakers as well. Any separate power amp you buy must be rated to drive 4 ohm loads, most are.

You have the speakers connected properly.

tonyb

When you add an amp, you'll hook the speakers up differently. You'll use one set of RCA interconnects from the receivers front left and right pre-outs, to an amp's left and right input. Then you'll connect the speaker wire to the amp, instead of the receiver.

Used amps under 500....Parasound HCA 1200 OR 1500, B&k, Carver, a few others too but those are what most use when budget concerns are a priority.

jomat77

@F1nut that said...If I want to stick with the LSi series and run the full 7.1 surround, will I need to purchase a single 7 channel amp or multiple amps? How many watt amp would I need to really get the most out of those speakers (using the AVR 7300)? What is the best way to set this up if I were to add a pair of F/X's and a pair of 7's to the system? Thank you for the advice.

jomat77

@tonyb Thank you for the input. Are there any H/K amps that you might recommend pairing up with my system? One that might be from the same era as the 7300. (2004)

tonyb

I'm not up to speed on vintage HK amps, but I assure you, the Parasound or B&k choices would be better sounding imho. Having the same brand as your receiver means nothing, unless you just like having the same name plates, visually. Sound quality wise though, I'd look beyond HK in an amp.

jomat77

@tonyb I did want to try to keep the same name plates if possible. Only because I thought that components were engineered to go with one another. That said, I have no real issues crossing brands.
I'm just not sure how many channel amp I would need to get and how many watts I'd need to push these speakers I have...and want to add.

cfrizz

Welcome to Club Polk! Below are two amps that will power your hungry LSI speakers to their full potential, which is what you want to hear everything your speakers have to offer. Until you get an amp, please watch how high you push the volume knob.

It is more money then you have allocated, but it will be well worth the expense. An amplifier is something that you can keep through all other changes to your system. So start saving more money and keep a watch on Audiogon for a good deal.

If you want new, look at Outlaw Audio and Emotiva.

https://www.audiogon.com/listings/multi-ch-b-k-reference-200-5-five-channel-power-amplifier-11456-2018-01-18-amplifiers

https://www.audiogon.com/listings/lis8fc5f-sunfire-cinema-grand-200-5-serviced-bill-flannery-multi-ch

tonyb

There's a 5 channel B&k amp right now in our own flea market for 700.

cfrizz

tonyb wrote: »

There's a 5 channel B&k amp right now in our own flea market for 700.

Jomat, you should jump on this deal, it will make all the difference in the world to your system.

jomat77

@cfrizz thank you for the input. I'm glad I posted on here before I damaged the system. I was cranking it up a little. I got a little excited about hearing music in my house that sound really good! lol
Nothing distorted and the receiver never got hot, so hopefully I didn't damage anything.
Can I still use the system as it is with the volume low, or should I not even be using it until I get one of these amps? I will be pretty bummed out if that's the case. I can't afford anything that expensive right now. I only paid $675 for everything I got which I thought was a decent deal. I'll have to keep saving like you said. I don't want to wreck anything and I'd definitely like to hear what these speakers are capable of! Thank you again for the advice and the links.

jomat77

Unfortunately I can't swing it at the moment. I will keep my eyes out for stuff though.

cfrizz

Yes of course you can still use your system, just be careful with how loudly you play it.

You didn't do any damage, you would know if you did, because something wouldn't sound right.

jomat77

Its awesome to know this system can sound even better. I was amazed at the sound I was already getting out of it. Benefits of not knowing any better I suppose!

K_M

You are using a sub......
Define.."not much bass"?

Could it be room related, or sub crossover frequency related?

If anything the Lsi15 have an abundance of midbass sound.
What frequency range is lacking?

What is the room layout, and where are you sitting in relation to the speakers?

haimoc

To me, LSI15 speakers are weak and shy with bass. I owned a pair and powered them with Plinius 9200 integrated amp.

bcharlesxpl

I'm in no way an expert and new to high end audio with my LSI7's. Just want to say be careful cause I just fried one of my speakers. Probably something dumb I did that I should have picked up on before having issues.
Also, I'm jealous of your LSI15's. I love the sound from the LSI7's and can only imagine how those sound.

mpitogo

All good suggestions but in 2005 the HK7300 was top of the line, In a review here is what they said

“It's refreshing to see that HK does not fudge its amplifier specs. In surround mode, the AVR 7300's seven channels are rated at 110Wpc into 8ohm, 20Hz–20kHz, <0.07% THD, all channels driven. The 2-channel output is rated at 125Wpc, both channels driven.”
Read more at https://www.soundandvision.com/content/harman-kardon-avr-7300-av-receiver#L8VJk6Qz42juOTMO.99

Anyway to me that seems like still a decent amount of power considering most now a days spec out wpc @1khz and only 2 ch driven. So this leads me to think it maybe calibration, crossover, speaker setting or phase. Check to see if the previous owner has any settings for their room. Best would be to factory reset to get a good baseline. If you want the towers to go full range, check if they’re set to large. If the towers are also setup in parallel check the cabling so both are in phase, sidefiring subs you may get cancellation.

Enjoy, that is a good deal of a system you have there.

Legender

Not that this answers any of your questions, and might just introduce more, but this was discussed in 2005, here:
http://forum.polkaudio.com/discussion/30650/harman-kardon-7300-plus-lsi15s