how to run a car sub in house

Re: how to run a car sub in house

'Car sub' and 'home sub' are just marketing terms. A sub doesn't care where it is run as long as it is in the correct enclosure and powered properly. The enclosure is determined by the driver's Theile/Small parameters and the goals of the designer. In reality, there are some subs that require such a large enclosure that they can be considered strictly home subs and some subs that do not produce very low bass so they can be considered car subs.

The subs I use in my theater are similar to the Audiopulse Axis 15's. They are currently in 3.5 cubic foot sealed enclosures powered by a Behringer EP-2500. I use a Behringer Feedback Destroyer as a parametric EQ to tame the inductance hump at 55hz and boost the low bass at 17hz.

Sometimes in the past people have asked this question and they were really asking how to run a car amp in the home. That is a waste of time and money. There are numerous pro amps and plate amps that can power almost any sub on the market.

-Robert

Re: how to run a car sub in house

This has been done a few times but not many. There are many, many subs on the market that will out perform a JL for less money. Have you modeled the sub in WinISD or Unibox to see what type of enclosure works best?

Dozens if not hundreds. You should choose your amp based on the enclosure design and the impedance of your sub.

Thermal power ratings are almost useless in home theater subs. Most of the time they will run out of excursion long before reaching their thermal limits. But this is enclosure dependent.

The Behringer and all pro amps plug into a standard 110v AC wall socket. You connect the audio inputs to the LFE output of your receiver using RCA to 1/4" mono plug adapters. You connect the amp's speaker outputs to the subwoofer driver. Plate amps work the same except no adapters are needed and the amp mounts on the box. Pro amps give you more power for the money. Plate amps are easier to configure and make for a cleaner looking enclosure since you never see the amp.

Please, please start using capitalization and puctuation. It makes things much easier to read. Also, don't send me personal messages with technical questions. That is a disservice to this forum because no one can search the PM's.

-Robert

Re: how to run a car sub in house

First thing, you have to get the car inside the house.

Re: how to run a car sub in house

Plate amps:
Parts-Express.com - Search Results
Elemental Designs

Pro amps:
Shop Pro Audio, Live Sound, Live Power Amplifiers | Musician's Friend

I can't recommend one without knowing the voice coil configuration of the driver and your enclosure design.

-Robert

Re: how to run a car sub in house

I'd put it in a 100L to 150L, sealed box. Power it with one channel of a pro amp like a Behringer EP-2500. If you go with something from QSC, Crown or Carvin then keep it around 1,500w into a 2 ohm load.

Your sub has dual 1.5 ohm voice coils. That makes choosing a home amp very difficult. Plate amps won't drive that load for very long without overheating. Pro amps shouldn't be bridged into that load unless you go with a very expensive model. Even then, I wouldn't do it.

As I mentioned earlier, JL is great sub but not a great value. I modeled an Elemental Designs 19Ov.2 (18" driver for $250) and it will get 5db lounder than the JL in the same 150L box with the same input power. I get similar results with the Exodus Audio Maelstrom-X and it has XBL^2 built into it.

-Robert

Re: how to run a car sub in house

That is a little simple, but yes. But like I said, the W7 is a difficult load to drive so plate amps are out of the question. Does your receiver have an LFE output?

You are welcome. Thank you for giving a hint about your age. I understand your posting style now. It is exactly like my 15 year old niece. It also explains your fixation of JL. In a few years you will understand value vs. marketing. When you decide to upgrade to something better and a lower price, come back here and I'll help.

-Robert

Re: how to run a car sub in house

I'm really not sure what you mean in your last post. You can use an iPod and/or an iMac as a source if they are connected to the appropriate input of your Onkyo.

-Robert

Re: how to run a car sub in house

My system as an example. All of my audio/video sources like my DVR's, XM radio, CD player, etc. are all plugged into my Pioneer receiver. The Pioneer is connected to 5 (and soon to be 7) speakers by speaker wire. The LFE (subwoofer) output is connected to my equalizer and then to my Behringer amp by subwoofer cables. The amp is connected to my two subs by speaker wires.

There is no standard way of measuring wattage on a PC system. Take those specs with a grain of salt.

Get a more powerful amp.

The specs are the specs. Each of the two voice coils are 1.5 ohms nominal (average). If you wire them in series you will present a 3 ohm load to whatever amp you use. If you wire them in parallel you will present a .75 ohm load to whatever amp you use. The price to value ratio as well as the voice coil combination make this a very difficult sub to work with in a home enviornment. Have you bought this sub yet? Why are you choosing this sub?

We are back on the Logitch amp? If so, then no you won't have 376 watts at 4 ohms. Not all amps double their wattage when you half the resistance. Some only get a 50% gain. Others will go up in smoke because they were never designed to drive a lower impedance load. And there is no such thing as under powering something. You did look at the other JL specs? The sensitivity is rated at 1w/1m. They fed a 1w signal to the sub and measured how loud it was. 1 single watt and the sub worked.

Which amp? The Logitech running at 3 ohms (voice coils of the JL wired in series) - I have no idea. My guess is that the amp was purpose built to drive the sub it came with so no flexibility of driving lower impedance loads was built in. It will either shut down or burst into flames. Other amps - I don't know. Some of the pro amps I linked to may drive each voice coil as a stereo load but it will require you to use a QSC or Crown amp. Those are the more expensive models.

Let me ask again, why this sub?

-Robert

Re: how to run a car sub in house

What model Onkyo do you have? I'll need that to get started.

-Robert

Re: how to run a car sub in house

Hookup diagrams for your receiver - link. In the picture below, you see a cable between the receiver and the sub. That is a subwoofer cable. Any of those cables will work to connect a subwoofer's plate amp to your receiver. But I recommended a pro amp. You would need an adapter like this since pro amps don't have RCA jacks, they have 1/4" mono phono jacks.


Is this good enough to get your started on connecting everything?

I'm again confused by the "question" so here is the best that I can do. The Onkyo is the control center for all of your source components - DVD, CD, radio, iPod, x-box, etc. The link above tells you how to connect your sources. The Onkyo also has amplifiers that power multiple speakers and a line level output to be sent to a sub amp.

-Robert

Re: how to run a car sub in house

The Behringer is the best value in pro amps. They aren't as robust as a QSC but then again, you aren't going on tour with this setup either. Also, should only use 1 channel of the amp. At 2 ohms, the EP-2500 puts out 800w continuous at 20hz. So at 3 ohms, you are looking at around 600 true watts. That is more than enough to shake a house. You can wire up each channel of the amp to each voice coil on the sub but you will be pushing a load that the Behringer is not designed for. At best it will get hot and shut down. At worst, you will fry the output transistors and your amp becomes a very large boat anchor.

Plug the sub cable into the LFE out of the Onkyo. Plug the other end of the sub cable into the RCA jack of the Radio Shack cable. Plug the 1/4" mono plug of the Radio Shack cable into Channel 1 of the amp. Connect speaker wires from channel 1 speaker connectors on the amp to the sub. Wire the sub in series. I'll leave it to you to find one of 1,000 diagrams on how to wire a dual voice coil sub. And a correction, that is NOT a headphone jack. That is a 1/4" mono plug. There is a very big difference even though they look similar.

No your Onkyo doesn't have an input labeled iPod. It doesn't matter. My receiver doesn't have 3 inputs labeled DVR but I have 3 DVRs connected to it. Just get a cheap docking station off of Ebay. I picked up one for my wife for $15 shipped this week. Connect the line output of the docking station to the CD input on the Onkyo with a 1/8" stereo to dual RCA cable. I'm not sure how it will sound though. It really depends on the bit rate of the music that you have. I'm extremely picky and want CD quality. I do not like the sound of compressed music in the house. But in my Nissan and my wife's Lexus, we both listen to compressed music since it is not a great listening environment and we sacrifice quality for convenience.

-Robert

Re: how to run a car sub in house

Ignore the cables mentioned earlier. All you need is Radio Shack part number 42-2373. Your other answers are in the pic below.