Sub help

[elpruss]

I just installed a Zapco ST-5X, rated at 80X4 and 160X1 @ 4 ohms, paired with JL Audio C2-650 components and one JL Audio 10W0V3 sub (4ohms, 300 watts RMS)

I'm disappointed with Zapco because their website says the amp is rated 80X4 + 350x1 @ 4 ohms, but after getting the amp and reading the manual, it says 160 @ 4 ohms and 320 @ 2 ohms.

I set the gain by ear using a 40Hz sine wave, and it seemed to start clipping really low (like at 30%). I'm not sure if it was clipping or another vibration in my vehicle I was hearing, but I think I got it right.

Anyway, bottom line is that I'm not happy with the bass output. I don't want to rattle windows on homes or anything, but currently the highs/mids seem to overpower the base.

So, would I see a significant boost in sub output by upgrading my sub to a JL Audio 10W1V3-2 which is a 2ohm sub, rated at 300 watts RMS and should increase the amp output to 320 watts RMS?

I really don't want to add another amp.

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[BOOMINGRANDPA 5,000+ posts]

If sub is in a sealed box easiest way to make system later without replacing sub or amp is get a ported box (tuned 36hz or lower if u want decent sq) that power is enough for that sub, ported would most likely be quite a bit louder.. until u do something like that adjust mids down some and make sure treble on hu is at 0.. u don't want to bridge amp to a 2 ohm sub bridge 4 ohm load is already = to 2 ohm so if u did that it would be 2ohm bridged =1 ohm load

 

[Cm_low]

Never worked with much jl or zapco equipment but I would think that should be a decent and significant upgrade. 360 watts to a sub is still not gonna be very loud but as from your explanation your not looking for that extreme loud setup but rather sq with nice bass complimenting the mids and highs. I would say go for it because really you don't have much other choice beyond that if you don't want to upgrade to a larger amp for the sub. Still sounds odd that you were clipping at only 30% gain though. Another option you have is to take it to a audio store/installer and have them hook it up to an o scope to make sure you are really clipping and there is not anything else going on.

 

[elpruss]

Yes, it's in a sealed, custom made enclosure under the back seat of my crew-cab pickup, space is limited so sub options are as well. I do think I could have a ported box built that would fit, just not sure. None of the channels on the amp are bridged, it has a single 5th channel sub output to a 4 ohm sub. I'm considering changing the 4 ohm sub to a 2 ohm sub (no bridging), which would place a 2 ohm load on the amp and produce 320 watts RMS vs the 160.

 

[elpruss]

I did consider taking it to the local audio store for tuning, but I'm also going to replace the HU soon (already have just need to find time to install) so was going to re-tune with new HU to see how that works out first. I thought 30% seemed low as well, but the mids/highs are also at about 30%, but those speakers are only rated for 60 watts RMS and are connected to 80 watt RMS channels.

 

[elpruss]

To clarify; this is exactly what the amplifier manual says (I didn't have the manual in front of me when I first posted this).

RMS Power/Channel at 4ohms - 80WX4+160X1

at 2ohms - 120WX4+350WX1

at 1ohms - No

Bridged at 4 ohms - 240X2+350WX1

Based on that, I'm not quite sure I can mix and match 80WX4@4ohms+350WX1@2ohms, any opinions? It almost seems like it has to be all channels 2ohms or all at 4 ohms.

 

[dsw1204]

You cannot run that Zapco's amp sub channel at 2 ohms, only at 4 ohms. I talked to someone at woofersetc (they are an authorized Zapco dealer) and they confirmed what I am saying to you. That may be your problem.

 

[elpruss]

You cannot run that Zapco's amp sub channel at 2 ohms, only at 4 ohms. I talked to someone at woofersetc (they are an authorized Zapco dealer) and they confirmed what I am saying to you. That may be your problem.

I also sent an email to the dealer I purchased from, but hadn't heard back yet.

The manual is not very clear, just a spread sheet and illustrations, and covers the whole line of ST-X Series products, not just this amp.

So it looks like when you bridge channels 1-2 and 3-4 or run channels 1-4 at 2 ohms it increases the sub output to 350 watts RMS @ 4ohms otherwise it's 160 @ 4 ohms.

So I guess I need to take a closer look at my tuning/gain.

 

[dsw1204]

I also sent an email to the dealer I purchased from, but hadn't heard back yet.
The manual is not very clear, just a spread sheet and illustrations, and covers the whole line of ST-X Series products, not just this amp.

So it looks like when you bridge channels 1-2 and 3-4 or run channels 1-4 at 2 ohms it increases the sub output to 350 watts RMS @ 4ohms otherwise it's 160 @ 4 ohms.

So I guess I need to take a closer look at my tuning/gain.

Yeah, that's a bit different than other manufacturers. Just have to make sure your sub is 4 ohms.

 

[elpruss]

Yeah, that's a bit different than other manufacturers. Just have to make sure your sub is 4 ohms.

Thanks... Saved me some $$$ buying a new sub and amp damage. Maybe I'll look for some 2ohm components so I can run the sub channel at 350.

 

[elpruss]

I sent an email to Zapco asking about my amp (it's the Zapco ST-5XII not the ST-5X as stated originally), and this is the response I received.

Hi Russell,

Looks like they packaged the new models before they modded the manual.

The early ST-5X bass channel was 350W at 4 ohms, and not stable at 2 ohms.

Customers are used these days to 2ohm bass. So…

The new ST-5XII bass channel is stable at 4 ohms and 2 ohms. It is 350W at 2 ohms

We need to adjust the web site as well. Thanks.

Regards,

John

 

[audiobaun 5,000+ posts]

It would be nice to run @2 ohm mono on sub stage.I think you may be a bit more pleased with that rather than 4 ohm.I really like 2 ohm all around to be honest for daily listening.Thats me though for daily listening/low volumes,not SPL

 

[elpruss]

Well I did turn my gain up, and am much more pleased with the bass output. I really don't think I was able to hear clipping with the 40hz tone, I'm guessing I was mistaking clipping for some other noise or rattle in the vehicle, because it sounds clean and distortion free at about 60% now.

I was considering 2ohm all around, but seems that 2ohm speakers are very limited.

 

[audiobaun 5,000+ posts]

Well I did turn my gain up, and am much more pleased with the bass output. I really don't think I was able to hear clipping with the 40hz tone, I'm guessing I was mistaking clipping for some other noise or rattle in the vehicle, because it sounds clean and distortion free at about 60% now.
I was considering 2ohm all around, but seems that 2ohm speakers are very limited.

Raw drivers open up a verity of choices for you.

 

[audiobaun 5,000+ posts]

Good to hear that you have gotten your system to sound much better.Rattles and vibrations/loose items lying around in the vehicle and non deadened panels and loose plastics are hard to eliminate these days,and time consuming to locate inmost newer vehicles these days.Takes time to locate them and address them.