Advice on replacing/upgrading subwoofer speaker in existing housing?? (1 Viewer)

[Chevy-SS]

Greetings,

The subwoofer in my existing setup breaks down (probably not the exact proper word) during hard bass hits (like cannon and explosion sequences). I want to upgrade the subwoofer speaker itself to better handle these events. The subwoofer is an aging Optimus Pro SW-12 and it appears to have a dual voice coil speaker.

My spare A/V Receiver (Onkyo TX-SV50PRO) sits in a closet and is used solely to power the subwoofer, while my main A/V Receiver is an Onkyo TX-SR601. I am feeding a low-level signal from the TX-SR601 to the TX-SV50PRO.

The whole setup actually works pretty good for me. I only listen at moderate levels. If I could simply get the sub to respond without breaking down, I'd be happy. I have the money to buy anything I want, but I just hate throwing things away if they are still working sufficiently. I guess you could just call me "thrifty", lol.

I'd be grateful for any help in selecting a new subwoofer speaker and for assistance in wiring it up.

Thanks

-

 

[Chevy-SS]

Greetings,

The subwoofer in my existing setup breaks down (probably not the exact proper word) during hard bass hits (like cannon and explosion sequences). I want to upgrade the subwoofer speaker itself to better handle these events. The subwoofer is an aging Optimus Pro SW-12 and it appears to have a dual voice coil speaker.

My spare A/V Receiver (Onkyo TX-SV50PRO) sits in a closet and is used solely to power the subwoofer, while my main A/V Receiver is an Onkyo TX-SR601. I am feeding a low-level signal from the TX-SR601 to the TX-SV50PRO.

The whole setup actually works pretty good for me. I only listen at moderate levels. If I could simply get the sub to respond without breaking down, I'd be happy. I have the money to buy anything I want, but I just hate throwing things away if they are still working sufficiently. I guess you could just call me "thrifty", lol.

I'd be grateful for any help in selecting a new subwoofer speaker and for assistance in wiring it up.

Thanks

-

 

[Robert_J]

It could be 1 of 2 things. First, your sub just can't handle the soundtracks in the new action movies. That is a combination of both the driver and the enclosure. Second, your receiver you are using as an amp doesn't have the capability of supplying enough power to the sub without clipping. Or it could be a combination of both.

Comments on text in pictures:
Yes, that is a crossover and yes those are capacitors. It's not an "or" type question. Caps are used in all passive crossovers. Yes, you can replace your current driver with a single voice coil model but you will have to change your amp as well or only use 1 channel of your amp.

How do you get the sub amp (aka receiver) to turn on automatically?

If you want to upgrade, I need more information. What is your budget? What sized sub is it? How large is the mounting hole? What is the enclosure volume in cubic inches? What is the diameter of the port? What is the length of the port?

-Robert

 

[Chevy-SS]

Robert,

Many thanks for the info.

There is a switched outlet on the back of my main receiver, and I have the spare receiver plugged into that, so both receivers turn on with one button press.

I ended up buying a $70 12" automotive subwoofer at WalMart and installed that into my enclosure. On the sub box, it said it was "optimized" for small enclosures. It was a single voice coil, so I used only one set of leads. I also noticed that I had my crossover limit set at 40hz on my main receiver (I am using the subwoofer pre-amp out to supply the signal to the spare receiver), so that was probably contributing to my problem.

Anyway, the problem is basically fixed. No more clipping (if that's what it was) or distortion. Though it does sound a bit boomy (not sure if that's the right word). Might it have a little crisper bass if I pluged the port?

Thanks again for the tips..........

Dave

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Since this is a ported enclosure

 

[brandonchenry]

check out svsound.com

that is the place to go to get world class bass at reasonable prices.

 

[brandonchenry]

never mind, sounds like your looking for less than I was thinking.

you might have fun building a DIY subwoofer.

Robert can tell you how to get that going.

Peace

 

[Robert_J]

Depends on the Theile/Small parameters of the Wal-Mart sub. But since it is a WM sub, I don't expect them to have any published specs other than an over-inflated RMS parameter. I was going to recommend this sub to you after I suggested that you seal up your port. This sub works great in a 1.2 cubic foot enclosure with about 200w.

-Robert

 

[JohnRice]

Just FYI, I have three of those RS units, and it is really more a passive bass module than a sub. The housing may be usable, in a completely minimal way. Now Robert has me interested in replacing the driver in one, plugging the port, bypassing the crossover and giving it a spin.

 

[Robert_J]

The PE 240w amp or the 300w BASH amp that is on sale would be good options to power your new sub.

-Robert

 

[Chevy-SS]

If you plug the port, what would you expect as a result?

And why do you call this a passive sub? It is rattling my house now, even with a moderate WM speaker............

thanks

 

[Robert_J]

Rattling is not the goal. Clean, effortless, deep bass is the goal. My theater room sconces rattled with my current sub so I took them apart and used rubber washers to keep glass and metal from touching.

-Robert

 

[Chevy-SS]

"Rattling" was the wrong word. The bass is pronounced and strong with no clipping or distortion at the levels I listen to. It is, however, a tad boomy. But I am starting to read up on this stuff and I am gonna experiment with my crossover settings and all the other speaker adjustments.

There is a lot more to this stuff than I ever realized. I never realized there was such a science to simple bass.

Thank you very much for the driver recommendation. I should have controlled my impetuous instincts and held off, then bought the one in your link.

Again, many thanks........

-

 

[Robert_J]

Read up on Dr's Theile and Small and their research into acoustical physics. It was these two that came up with the formulas on this page (click the links on the left side of the page).

Starting in the mid 90's, guys like Dan Wiggins, Thilo Stompler, John Janowitz, Scott Atwell (former owner of Resonant Engineering and current owner of Fi Car Audio & Ascendant Audio) and others started to push the limits of subs to the extremes. Take a look at the RE XXX 18" sub that Scott designed, Thilo's subs in those pictures or the Parthenon sub from Dan.

-Robert

 

[JohnRice]

Dave, I'm sorry to break the news, but it's a cheap bass module. Yes, it is better than Bose, or maybe more different than better. it gets some bass in, but the extension of this unit is not much. If you are using a Home Theater receiver sub crossover, you really should be bypassing the speaker level crossover in the RS unit. It will just screw things up.

So Robert, what if someone had a couple of the original SVS Plus drivers sitting around, how might it work with one of them in this cabinet with the port plugged. I also have one of those 300W Bash amps to play with.

 

[Chevy-SS]

Good idea. I am using the crossover filter that is built into my main A/V receiver. I will try this.

Thanks

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[Robert_J]

Hey! I have a pair of Plus drivers sitting around. I haven't tested them because I was cloning an existing SVS sub. I've been meaning to throw them on Woofer Tester 3 but I'm missing a precision scale. I've been planning on getting one to run double duty with speaker testing and ammunition reloading but reloading parts are difficult to find lately. If I find a scale that does ounces, I'll get them measured ASAP.

-Robert