PDA

View Full Version : LSi15 vs LSi9 + Subwoofer



tomhayes
10-26-2005, 07:25 PM
Which ones for 70% music, 30% HT?

I'll be driving it with a Harman Kardon Signature Series amp so power is not a problem.

I'll probably get a sub later with the 15s for the real rumble needed fro blockbuster movies.

I'm more interested in how the LSi9s stack up next to the LSi15s for music. I understand that the 15s will have more bass unless a sub is used.

I started this thread even thought there was another thread about it. But that thread spiraled into a discussion on gay marriage so I thought we could start one that focused on the LSi15s vs. the LSI9s both with and without a sub.

McLoki
10-26-2005, 07:42 PM
If it was the other way around (70%ht, 30% music) I would say get the 9's. Since it is mainly for music listening - I would say get the 15's.

Michael

tdeluce
10-26-2005, 09:36 PM
You want the LSi15s AND an accurate subwoofer...

tomhayes
10-27-2005, 04:14 AM
You want the LSi15s AND an accurate subwoofer...
Well I bought the LSIs tonight. NExt up a sb.

tdeluce
10-27-2005, 11:45 AM
Well I bought the LSIs tonight. NExt up a sb.


congratulations - you are going to love them...

audiobliss
10-27-2005, 02:05 PM
Congrats! Which ones did you get?

tomhayes
10-27-2005, 02:16 PM
Oh I bought the LSI15s and a LSIc.

I do think I need a sub for booming rap music and action moves. I need to "break these in" this weekend and then decide.

tomhayes
10-27-2005, 02:18 PM
Pic
http://www.polkaudio.com/forums/attachment.php?attachmentid=11790

Details:
http://www.polkaudio.com/forums/showpost.php?p=364529&postcount=70

audiobliss
10-27-2005, 02:23 PM
That's awesome! I'd also recommend a sub for movies, but I probably wouldn't use one with those for music.

Do you have specs for or a link to the specs for your receiver? Never heard of the Signature Series from HK. Sounds interesting.

tomhayes
10-27-2005, 02:31 PM
Do you have specs for or a link to the specs for your receiver? Never heard of the Signature Series from HK. Sounds interesting.

The manuals for the HK stuff are at: http://www.cinenow.com/us/downloads.php3/mk,13/

Power Output:
5 x 100 watts @ 8 ohms
20Hz – 20kHz, <0.03% THD, All Channels Driven
5 x 150 watts @ 4 ohms
20Hz – 20kHz, <0.03% THD, All Channels Driven

High-Current Capability:± 100 Amps
Frequency Response:1Hz – 170kHz ± 3dB
Power Bandwidth:<1Hz – >100kHz
THD/IMD:<0.03% at rated output

audiobliss
10-27-2005, 02:36 PM
Wow. That's pretty awesome for a receiver. And given it's HK, those ratings are probably pretty accurate.

aaharvel
10-27-2005, 02:39 PM
High-Current Capability:± 100 Amps

check that out. That's what REALLY matters.

polkatese
10-27-2005, 02:55 PM
Not questioning the accuracy of the specs, but is that really PHYSICALLY possible to push 100amps of current from a (max) of 20Amps outlet? Or I am comparing Apple and Orange here?

tomhayes
10-27-2005, 03:22 PM
Not questioning the accuracy of the specs, but is that really PHYSICALLY possible to push 100amps of current from a (max) of 20Amps outlet? Or I am comparing Apple and Orange here?
I have no idea what High Current really means. I just have always like the way Harman Kardon equipment sounds. I have an AVR75 as my first real, good reciever and have always like their sound.

Sami
10-27-2005, 04:16 PM
Not questioning the accuracy of the specs, but is that really PHYSICALLY possible to push 100amps of current from a (max) of 20Amps outlet? Or I am comparing Apple and Orange here?
I don't know but 20A * 120V = 2400W so running all your HT gear through 20A fuse should not be a problem. Lets say 500W subwoofer + 7 * 200W surround amp, that's a (theoretical) total of 1900W IF running at max on all channels. That still leaves plenty for the rest of the gear.

RMS is sine-wave (Ep /(sq root 2) * (Ip /(sq root 2) = (Ep * Ip)/2 (if I understood correctly).

mldennison
10-27-2005, 05:20 PM
I'll be driving it with a Harman Kardon Signature Series amp so power is not a problem.

mmmmmmmmmm, my friend has been running the signature pre/pro, very nice amp... that is defaintely going to make the lsi's shine!

tomhayes
10-27-2005, 05:48 PM
I ordered a subtoday :)
Velodyne SPL1000 II Cherry 10 Inch Powered Subwoofer for $699
http://www.onecall.com/ProductDetails.aspx?bid=38&sHist=12-110%2c6-38&Page=2&id=21036

They have the maple for $599.

It's the previous model version without the remote, but who needs a remote?

It'll be here tommorrow.

reeltrouble1
10-27-2005, 06:09 PM
Where are the EE's when you need them!!!! I am a sound not a science guy, but once many years ago was an EE major, I believe this is apples and oranges. A thought.

We know through ohm's law that I=V/R. So on a 20 amp circuit breaker if V=120 then when R exceeds 6 ohms the breaker trips. Now a 100 ft run of 12ga wire only has a total resistance of .159 ohm you have to add the resistance of all devices the line is supplying to reach your total load. If the R then exceeds 6 ohms the breaker pops to prevent the heat the increased current creates from burning up the wire.

A stereo amp contains a power supply that converts 110-volt alternating current into lower-voltage direct current. This direct current is ultimately what powers the speakers. The power supply first lowers the voltage with the help of a transformer. Alternating current from the power line flows back and forth through a coil of wire in this transformer, the primary coil, and causes that coil to become magnetic. Since the coil's magnetism reverses 120 times a second (60 full cycles of reversal each second), along with the alternating current, it produces an electric field--changing magnetic fields always produce electric fields. This electric field pushes current through a second coil of wire in the transformer, the secondary coil, and transfers power to that current. There are fewer turns of wire in the secondary coil than in the primary coil, so charges flowing in the secondary coil never reach the full 120 volts of the primary coil. Instead, more current flows in the secondary coil than in the primary coil, but that secondary current involves less energy per charge--less voltage. In this manner, power is transferred from a modest current of high voltage charges in the primary coil to a large current of low voltage charges in the secondary coil.

Having used the transformer to produce lower voltage alternating current, the power supply then converts this alternating current into direct current with the help of four diodes and some capacitors. Diodes are one-way devices for electric current and, with four of them, it's possible to arrange it so that the alternating current leaving the transformer always flows in the same direction through the circuit beyond the diodes. The diodes act as switches, always directing the current in the same direction around the rest of the circuit. The capacitors are added to this circuit to store separated electric charge for the times while the alternating current is reversing and the diodes receive no current from the transformer. The capacitors store separated charge while there is plenty of it coming from the transformer and provide current while the alternating current is reversing. Overall, the amps power supply is a steady source of direct current.

Whew, so note that I started on my own with this, then had to go look some of technical things. However, I believe you can see that the amp can in fact create the high peak 2 peak current you see listed in the specs from the house line. Whether this H&K is capable of doing it I dont know, but it is possible and I have no reason to doubt the spec because I have never heard the amp here. H&K has a decent rep for putting together excellent top end entry level gear.

RT1