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Am I shorting myself power? Long time bass head out of practice

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Sidebar- the enclosure sold to me does not mimic exactly the recommendation from RF; Actual box measures 13.65”H 16”W 17.5”D (11” to chamber I believe based on pic)
RF says 14”H 25”W 12”D. Wondering if this needs to be addressed also for general principle.
Thank you all sincerely for getting me to this point! Cell below if anyone wants to text me info
Patrick Stewart
843-647-8807
It would seem that box is way to small, Any idea what the tuning freq is? I would be tempted to seal the port and see how it sounds.
 
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Even if you can’t exchange for a D2 that amp will have plenty of power at 8 ohms bridged.

And I know we look down on prefabs 🙄 but I’m sure it will still knock. That could always lead to a fun project if your son gets the bug. Build a new box together later.

I’m sure know but in case if that amp ever has issues it would be easy to get repaired!
 

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The shop used what they have on hand.
You typically do not order d2 subs these days.
No point. The only 4 channel amps with enough power for a sub are much to expensive for the average consumer.
And not very often do people put down the coin for a dual sub stage. Especially considering the state of subwoofers these days.
And when they do again you want d4 to get to 1 ohm Especially easy.
So this is install is par for the course. Especially considering those guys have never heard the words crossover and cards corresponding in the same sentence.
So ya they just made it work.
 

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With all due respect...this is bull.

1) That Rockford could be used to power a small town

2) The OP is trying to pass-down his passion for the hobby to his son - what better way than to share an absolute HALL OF FAME amplifier with him?

3) As much as people LOVE class D for efficiency, A/B kicks it in the arse 9/10 times in SQ (until you get in to some $$$ amps)

I own some pretty good Class D stuff. NONE of it is in my SQ system.
I had a feeling that my comments would ruffle some feathers.

Bottom line, a 2 channel amp wasn't the right call for this install. Could it be done? Surely, but you would be limiting your sub choices in a time of record low inventory of everything. And a modern mono amp would have fit In that panel without any issue at all

That said, ru. The coils in series and bridge the sub on this amp if you must use it.
 

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Yeah likely used what they had but they may have a D2...

Not to derail this any more but why would you do a 1-ohm dual sub setup and not a 1-ohm single sub setup 😉

The shop used what they have on hand.
You typically do not order d2 subs these days.
No point. The only 4 channel amps with enough power for a sub are much to expensive for the average consumer.
And not very often do people put down the coin for a dual sub stage. Especially considering the state of subwoofers these days.
And when they do again you want d4 to get to 1 ohm Especially easy.
So this is install is par for the course. Especially considering those guys have never heard the words crossover and cards corresponding in the same sentence.
So ya they just made it work.
 

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Yeah likely used what they had but they may have a D2...

Not to derail this any more but why would you do a 1-ohm dual sub setup and not a 1-ohm single sub setup 😉
Still dont get it....money. what 1ohm stable amp is made by any mainstream manufacturer that isnt 1000 dollars and also isnt on amazon?
Because thats the only thing a shop will carry.
A shop isnt going to have any of the stuff talked about on here.
Sorry if i missed it..but how much was payed here? I
 

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Actually, that amp was made before RoHS was implemented. It would not be repairable easily, because the components have lead, and the new/RoHS compliant components will not be of the same quality as 1990s caps, FETs, etc.

I'm not talking out my butt here...lol. I have worked in CM factories, making $1.5M Cisco servers and racks, parts for Raytheon, and even the Apple "Trash Can" Mac home computer. MSFT, AAPL, BMW, and several other companies trust the products I drew-up the B.O.M.s for.

If you're ever in a shopping mall, talking on a cell phone with GREAT reception, the mall likely has US Cellular repeaters installed, made by a company named Aviat. Guess who redrew the B.O.M.s for Aviat, so that RoHS components could be used for late-stage refurb?? Myself, and my cubicle mate, Mike.

Not trying to sound like a know-it-all, but I know enough to tell you:

1) That amp is HOOKED UP WRONG
2) The sub is not the problem - the install is

Patrick, the box is tuned that way for what sub? Their specs are BS. You cannot "tune" a box unless you know the T/S specs. At least, not correctly.

If I was in Charleston, I'd fix this FREE, just because I feel bad that you spent $ on that. -- o.c.
 

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Rockford makes quite a few just as an example.

Not all shops are vacant wastelands barely hanging on. Sounds like a lot of experience with marginal sales people as well. Don’t want to clutter this guys thread anymore.

His 500.2 will work great even if they don’t have a D2. That prefab will sound fine. Unfortunately whoever sold him the stuff wasn’t up to speed on 20+ year old amps. /thread

Still dont get it....money. what 1ohm stable amp is made by any mainstream manufacturer that isnt 1000 dollars and also isnt on amazon?
Because thats the only thing a shop will carry.
A shop isnt going to have any of the stuff talked about on here.
Sorry if i missed it..but how much was payed here? I
 

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Discussion Starter · #31 ·
Actually, that amp was made before RoHS was implemented. It would not be repairable easily, because the components have lead, and the new/RoHS compliant components will not be of the same quality as 1990s caps, FETs, etc.

I'm not talking out my butt here...lol. I have worked in CM factories, making $1.5M Cisco servers and racks, parts for Raytheon, and even the Apple "Trash Can" Mac home computer. MSFT, AAPL, BMW, and several other companies trust the products I drew-up the B.O.M.s for.

If you're ever in a shopping mall, talking on a cell phone with GREAT reception, the mall likely has US Cellular repeaters installed, made by a company named Aviat. Guess who redrew the B.O.M.s for Aviat, so that RoHS components could be used for late-stage refurb?? Myself, and my cubicle mate, Mike.

Not trying to sound like a know-it-all, but I know enough to tell you:

1) That amp is HOOKED UP WRONG
2) The sub is not the problem - the install is

Patrick, the box is tuned that way for what sub? Their specs are BS. You cannot "tune" a box unless you know the T/S specs. At least, not correctly.

If I was in Charleston, I'd fix this FREE, just because I feel bad that you spent $ on that. -- o.c.
You’re the man for even offering as it stands. Yeah the box was apparently a trade-in from another vehicle “tuned” to whatever the Amazon cut sheet says it is. It’s a generic Pre-fabbed buy in bulk box. I wish you were in Charleston too haha to help me fix this. Considering this amp once wired correctly in itself is to stay in the Jeep, In your opinion is the P3D2-12 the ideal single woofer/enclosure in and of itself? Have to keep small single box setup bc of baseball and carpooling gear and kids with travel ball.
 

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Do you have any way to adjust the subwoofer level from the OEM system?

Because if it sounds great now, with the gain and bass boost at 0, it probably won't sound great when you double the power going to the subwoofer, it you can't lower the output level accordingly. Maybe even the subwoofer is wired in series for a 8ohm load now, going to a single channel just to keep the output level down for a balanced sound?
 

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The Rockford sub should be sufficient, yes.

My opinion is less important than your ears!

That said, I don't own any Rockford subs from post-1993/94 lol. But, they are probably better today than they were even 5 yrs ago, and so on...

Today, manufacturing tolerances are incredible. It's one reason China can offer equal quality manufacturing, if you source the right suppliers.

The Infinity Kappa 1200Ws I recently installed are Chinese made, and are pretty stout.

"Ideal" is sort of hyperbole in car audio. I'd need to sweep your cabin for resonant freq., reflection, and gauge your low-end boost or the "transfer function" of a sub model in an enclosure, just to get an idea of what's optimal. Even then, when you load three people, a case of Deer Park, two golf bags and a Great Dane in there, things compound even further.

In other words, real-world results can me modeled, but are often not "exact" upon implementation.

For example, I have a 15" woofer with a Qts of .703, which in theory, should perform SPECTACULARLY in a free-air or infinite baffle setup. Installed in my car, it sounds like wild boars fighting when asked to hit low and hard. But, drop a cheap Cerwin Vega Stealth 15 in the same car, and it sounds heavenly.

Start by ensuring the voice coils are wired in series, then run them to the amp as pictured and take a listen...

You mentioned it sounded okay, but you thought there was room for improvement. If it sounds better properly wired, then we can start messing with gains etc.

Once you wire it properly, shoot me a PM and I can answer any questions that you have about where to go from there with little to no more $.

-o.c.
 

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Oh..and the gain and bass may be all the way down because it's currently wired at 2 ohms, and getting a lot of power. BUT, it's not doing the amp any favors in that config.
 

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Discussion Starter · #35 ·
Do you have any way to adjust the subwoofer level from the OEM system?

Because if it sounds great now, with the gain and bass boost at 0, it probably won't sound great when you double the power going to the subwoofer, it you can't lower the output level accordingly. Maybe even the subwoofer is wired in series for a 8ohm load now, going to a single channel just to keep the output level down for a balanced sound?
I have the basic bass/mid/treble settings on the uconnect and bass is @ -8 for reference.
 

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Discussion Starter · #36 ·
The Rockford sub should be sufficient, yes.

My opinion is less important than your ears!

That said, I don't own any Rockford subs from post-1993/94 lol. But, they are probably better today than they were even 5 yrs ago, and so on...

Today, manufacturing tolerances are incredible. It's one reason China can offer equal quality manufacturing, if you source the right suppliers.

The Infinity Kappa 1200Ws I recently installed are Chinese made, and are pretty stout.

"Ideal" is sort of hyperbole in car audio. I'd need to sweep your cabin for resonant freq., reflection, and gauge your low-end boost or the "transfer function" of a sub model in an enclosure, just to get an idea of what's optimal. Even then, when you load three people, a case of Deer Park, two golf bags and a Great Dane in there, things compound even further.

In other words, real-world results can me modeled, but are often not "exact" upon implementation.

For example, I have a 15" woofer with a Qts of .703, which in theory, should perform SPECTACULARLY in a free-air or infinite baffle setup. Installed in my car, it sounds like wild boars fighting when asked to hit low and hard. But, drop a cheap Cerwin Vega Stealth 15 in the same car, and it sounds heavenly.

Start by ensuring the voice coils are wired in series, then run them to the amp as pictured and take a listen...

You mentioned it sounded okay, but you thought there was room for improvement. If it sounds better properly wired, then we can start messing with gains etc.

Once you wire it properly, shoot me a PM and I can answer any questions that you have about where to go from there with little to no more $.

-o.c.
Thanks man.
 

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With all due respect...this is bull.

1) That Rockford could be used to power a small town

2) The OP is trying to pass-down his passion for the hobby to his son - what better way than to share an absolute HALL OF FAME amplifier with him?

3) As much as people LOVE class D for efficiency, A/B kicks it in the arse 9/10 times in SQ (until you get in to some $$$ amps)

I own some pretty good Class D stuff. NONE of it is in my SQ system.
In agreement here. I used and still have older Rockford power and punch 800a2. If you throw out size and electrical, I would use them all day and every day over most class d amps. Clean and underrated on power. Very similar to my slash amps. The only reason not going in my next car is size.
 

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Also, even if this amp when fully unleashed can produce a huge amount of power (and it can, for sure!), it will also consume about twice as much power, in good old class a/b 50% (or so) efficency fashion. And that is also something to consider. It needs plenty of power and also cooling. As these run HOT when pushed. Speaking from experience, I had RF amps from this generation and the one before (landmines) when they were new.
 
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Also, even if this amp when fully unleashed can produce a huge amount of power (and it can, for sure!), it will also consume about twice as much power, in good old class a/b 50% (or so) efficency fashion. And that is also something to consider. It needs plenty of power and also cooling. As these run HOT when pushed. Speaking from experience, I had RF amps from this generation and the one before (landmines) when they were new.
Agreed it's a current hog! But for one sub wired to see 4 ohms mono, he shouldn't be dimming any headlights...

Patrick, you check the wiring on that sub yet, bud?
 
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