[devil84]

hi, i am add a sub to my HK system and using the following configuration

1. Technic Harness
2. Wavtech LOC
3. JL Mono Block
4. JL XD400.4 to potentially drive the underseats

question:
1) can the Wavtech LOC be powered from the Technic harness, would i need to run a seperate wire.

2) given i could be running two amps and a LOC, would a power distribution block be best?

[WretchedRefuse]

Originally Posted by devil84

...
1) can the Wavtech LOC be powered from the Technic harness, would i need to run a separate wire.

2) given i could be running two amps and a LOC, would a power distribution block be best?

1) I'm not aware that the Technic harness has a power wire. The one I'm thinking of just splits out and provides access to the speaker wires. In general though I would run a separate power wire so as to not overload a circuit that wasn't designed for it.
2) At the risk of repeating my reply to your first question, unless the Technic harness has a power line specifically devoted to powering accessories like a LOC, I'd run a separate power wire for it. Use an add-a-fuse type kit or tap into your amplifier power line rather than placing additional load on an existing circuit.

Having said that, why are you planning to use the LOC? If I recall correctly there are only two audio channels coming from the head unit.

[devil84]

Thanks. Because my oem system is Harmon Kardon and I need a loc to lower the signal

Ok so I need to run 3 power cables.

[WretchedRefuse]

Yes, I have the HK also and that's how I did it. I made sure to purchase a power amp that accepts speaker-level inputs. I think that most do, at least the dedicated subwoofer amps.

[devil84]

When you say high power amps? What do you mean?

Did you use a LOC as HK peaks at 28v and most amps only accept 20v input

[WretchedRefuse]

No I didn't use a LOC. I use the JL Audio RD500/1 amp, which features a speaker-level input that I feed directly from my HK head unit via the JL Audio RCA plug adapter. I don't see a maximum voltage spec for the amp but can attest that the arrangement works fine.

[devil84]

Ok that’s interesting as the RD500/1 maximum input is as follows

Switchable from 200 mV - 2 V RMS (Low) to 800 mV - 8 V RMS (High)

Have you tapped into the underseat signal via the JL adaptor. Technic and various others have already confirmed that they HK peaks at 28v so I don’t understand how your would work.

[WretchedRefuse]

Originally Posted by devil84

Ok that’s interesting as the RD500/1 maximum input is as follows

Switchable from 200 mV - 2 V RMS (Low) to 800 mV - 8 V RMS (High)

Have you tapped into the underseat signal via the JL adaptor. Technic and various others have already confirmed that they HK peaks at 28v so I don’t understand how your would work.

As I recall, I used the procedure from Page 12 of the RD500/1 manual, which explains how to calibrate the input sensitivity of the amplifier. I followed this and have never had a problem.

[devil84]

fair enough - as long its working for you.

does anyone know if i can power the Wavtech LOC by using the battery and ground connection at the amp (vs running another power cable to battery)

something like this

[WretchedRefuse]

Yes, that should work fine. What do you plan to use as the remote turn-on for the amp and LOC?

[devil84]

i am going to use the fuse box into the wavtech LOC - then use the remote out of the wavtech loc to feed both JL audio amps. i assume i can split the signal from the wavtech so it feeds two amps.

i heard the speaker input remote on for wavvtech is quite hit and miss when the volume is low.

[WretchedRefuse]

It sounds like you are going to have a killer setup. Be sure that you choose a circuit that is only active when the car is running. I also recommend using an add-a-fuse so as to not risk drawing too much current from the factory circuit.

Just curious, are you planning to use the stock speakers? With amps like those I'd expect you to go with something premium like BimmerTech or Bavsound.

[devil84]

Yeah I am hoping amping the underseats is worth it. The xd400/4 explicitly states it can give 150watts rms into an 8ohm load which is perfect for the Hk woofers. As per the various threads, the HK woofers are actually quite good.

I have replaced the door speakers with focal es100k. I like the tone of the focal