Subwoofer Install

[cowen]

Hi all. Recently installed a sub, i’ve gotten it all wired in and working (partially) with an amp, sub and hi low level adaptor (came as a wiring loom that extends the plug going into the back of my media unit in the glovebox). Everything seems to be working however it’s got almost no kick to it, is this something that’s being controlled by the media unit? Many thanks.

 

[WozzaB]

Do you have any bass coming from the sub?

When I fitted my active sub and 4 channel amp used a ISO T harness behind the CD unit and tapped into the front left/right speakers for the sub input, but it barely had any output, the helpful guys on here told me that with my particular setup the front left and right was only the tweeters so the sub wasn't receiving any low frequencies, I had to tap into the front door speakers on the ISO loom, which was on separate pins, and boom it's pounding now.

I'm not sure if you have a similar issue, as I had virtually nothing coming from the sub initially.

There's a useful pic of the wiring somewhere, but I can't find it at the moment.

 

[cowen]

Do you have any bass coming from the sub?

When I fitted my active sub and 4 channel amp used a ISO T harness behind the CD unit and tapped into the front left/right speakers for the sub input, but it barely had any output, the helpful guys on here told me that with my particular setup the front left and right was only the tweeters so the sub wasn't receiving any low frequencies, I had to tap into the front door speakers on the ISO loom, which was on separate pins, and boom it's pounding now.

I'm not sure if you have a similar issue, as I had virtually nothing coming from the sub initially.

There's a useful pic of the wiring somewhere, but I can't find it at the moment.

Yes there’s bass coming from the sub, just non existent even though it’s using a hi-low converter, which i’d assume is going to eliminate that problem? It’s been wired in before as you’ve mentioned and that still didn’t work, which is why i bought a converter. I’ll attach a photo of the adaptor i have. Not sure if it’s obvious in the photo but it’s an extension of the wiring harness with a vibe hi low already wired into it.

 

[WozzaB]

Yes there’s bass coming from the sub, just non existent even though it’s using a hi-low converter, which i’d assume is going to eliminate that problem? It’s been wired in before as you’ve mentioned and that still didn’t work, which is why i bought a converter. I’ll attach a photo of the adaptor i have. Not sure if it’s obvious in the photo but it’s an extension of the wiring harness with a vibe hi low already wired into it.

Well it should be getting a low frequency signal from that, what are the settings on the sub amp and also the Sound/EQ settings on the main unit?

I have the 125hz near max on the head unit EQ as if I lower it the bass output from the sub drops a lot, also the Sound Focus on 'Driver' drops the output a touch as well, so I have it set to 'All'

 

[cowen]

Well it should be getting a low frequency signal from that, what are the settings on the sub amp and also the Sound/EQ settings on the main unit?

I have the 125hz near max on the head unit EQ as if I lower it the bass output from the sub drops a lot, also the Sound Focus on 'Driver' drops the output a touch as well, so I have it set to 'All'

now that’s not something i’ve touched yet, i’ll have a play about with the cars eq and get back to you; many thanks !

 

[WozzaB]

now that’s not something i’ve touched yet, i’ll have a play about with the cars eq and get back to you; many thanks !

No problem, hopefully it's something simple like that, I'm no expert though!

 

[cowen]

No problem, hopefully it's something simple like that, I'm no expert though!

so, turning up 125hz to max defo got it kicking more, is there anything else i should change on my amp or manual equaliser?

 

[WozzaB]

so, turning up 125hz to max defo got it kicking more, is there anything else i should change on my amp or manual equaliser?

I've got the 'Sound Focus' on All and not Driver. apart from that the balance is set in the middle, I don't have a fader on my unit so, nothing to change there.
Depending on your amp, you might have gain, bass boost, HPF/LPF etc, you can have a play with the settings, there are lots of guides online if you're not sure on what's what

 

[Craig.]

The head unit should be left flat for the low frequencies and all adjustments done on the Amp. The Hi-Low converter just changes the speaker output to low voltage for the RCA input to the amp, not the audio frequencies.

The Amp does a lot of the heavy lifting with the audio filtering so adjusting the settings on the head unit creates unexpected and unaccounted changes to the audio profile which can be incorrectly amplified by the Amps design and can cause unexpected defects in audio quality and poor performance. Plus, it can shorten the life of the speakers.

Some amps actually have built-in Hi-level input, which usually create less "noise" than using a Hi-Low converters giving an overall better output quality.

Either way, your adjustments to change the Sub behaviour should be done at the Amp using the LPF and other adjustment features it has. You haven't told us which make and model the Amp and Sub are so can't help further.

 

[WozzaB]

The head unit should be left flat for the low frequencies and all adjustments done on the Amp. The Hi-Low converter just changes the speaker output to low voltage for the RCA input to the amp, not the audio frequencies.

The Amp does a lot of the heavy lifting with the audio filtering so adjusting the settings on the head unit creates unexpected and unaccounted changes to the audio profile which can be incorrectly amplified by the Amps design and can cause unexpected defects in audio quality and poor performance. Plus, it can shorten the life of the speakers.

Some amps actually have built-in Hi-level input, which usually create less "noise" than using a Hi-Low converters giving an overall better output quality.

Either way, your adjustments to change the Sub behaviour should be done at the Amp using the LPF and other adjustment features it has. You haven't told us which make and model the Amp and Sub are so can't help further.

I know you're replying to the OP, I do get what your saying, and I should have mentioned that to the OP.

But If have my EQ flat then the sub just doesn't hit as hard, despite what I do with the amp on the sub, also my mids in the front doors lose their punch.

I have an Audison APBX 10 AS2 sub, connected via high level input, luckily the amp on it 'reads' the incoming signal and will make adjustments before the signal hits the driver if it's going to cause clipping, but I do appreciate most amps won't have this feature, so you're spot on making sure the OP is aware.

Just my personal experience in this particular car, I've always had a sub output on the head units I've had previously, so easier to set the various speakers.

 

[Craig.]

I've not fitted a Audison APBX 10 AS2 but I do know that it has it's own "Bass Boost" adjustment along with the gain and LPF, have you adjusted that prior to adjusting the head unit?

Small adjustments to the EQ on the head unit is generally fine, I did mean any extreme differences but completely missed out that crucial detail ha!

Also, artificially bass boosted audio tracks could cause issues if not used correctly as a nugget of FYI. Not been mentioned but worth knowing.

 

[WozzaB]

I've not fitted a Audison APBX 10 AS2 but I do know that it has it's own "Bass Boost" adjustment along with the gain and LPF, have you adjusted that prior to adjusting the head unit?

Small adjustments to the EQ on the head unit is generally fine, I did mean any extreme differences but completely missed out that crucial detail ha!

Also, artificially bass boosted audio tracks could cause issues if not used correctly as a nugget of FYI. Not been mentioned but worth knowing.

I've spent quite a while adjusting the settings on the amp, bass boost is something I usually avoid using, but I did have a play with that out of curiosity, but the only thing that really got the sub shaking the car was rasing the 125hz eq pretty high on the head unit. For a fairly compact sub, it's pretty phenomenal!

I will say that for 75% of the music I listen to, D&B, old school hip-hop, garage etc, I like it sounding very bass heavy, however I'll turn the sub down a bit via it's remote when I'm listening to other stuff like a bit or rock etc.