Need Help! Confused about No of amps, and total output

T

TheEarthquakeMaker

Enthusiast
So I built a beast of a subwoofer enclosure, I based it on the GoldenEar Forcefield 5, except doubled. I have two 900w 4Ohm DVC Alpine X-W12-D4'S firing forward and two Earthquake 12" SLAPS passive drivers firing downward.
Currently it's running off a Dayton Audio SPA1000, they're currently wired to put a 4 Ohm load on the amp (the lowest impedance my plate amp can safely run at)
BUT, I have an extra SPA1000, so my question is, if I run one amp per sub, it would need to run at 8 Ohms, only outputting 450w as opposed to the current set up of 1000w at 4 Ohms.
Which will hit harder ?
Two subs running at 4 Ohms each sharing 1000wrms, or,
Each sub running at 8 Ohms, each with its own independent 450wrms ?
I might be asking a dumb question, but please be kind, I'm trying to learn, please help me if you can
 
lovinthehd

lovinthehd

Seriously, I have no life.
IMO won't really matter as far as impedance/power goes alone....more depends on the actual drivers and passive radiators and the box you're using. You could look at various wiring charts for how you can setup amp/sub impedance.
 
T

TheEarthquakeMaker

Enthusiast
I have spent weeks going over impedance charts, reading thorough, technical info. And I can't find any answer to my question.
I did state exactly what drivers, passive radiators, and amp I have, and the enclosure design style. The only extra info I can think to give you is the enclosure volume (1.2 cubic feet) and using the weights on the PRs, it's been tuned to 27Hz, which is what my driver's specs call for.
Is there any more info I can give you to help give a more clear picture ?
What I really want to know, is,
Two 900wrms subs + one Amp = 4 Ohm load, and 1000wrms output shared between the two subs.
Two 900wrms subs + two Amps = 8 Ohm load and 450wrms each.
Will it perform any differently ? Would I be adding any perceivable volume, or will I get the exact same effective output, and just have altered the power efficiency of the unit ?
Even more simply, should I smash this extra amp into that enclosure for more output, a "harder hit", or, would it be more wise to leave this enclosure the way it is and save the amp for my upcoming "infra-sub" project ?
(An 18" Dayton Sub in a 304L enclosure with x3 4x32" ports )
Any advice is useful, I'm trying really hard to learn this subject as thoroughly as I can, given my limitations.
 
T

TheEarthquakeMaker

Enthusiast
IMO won't really matter as far as impedance/power goes alone....more depends on the actual drivers and passive radiators and the box you're using. You could look at various wiring charts for how you can setup amp/sub impedance.
I know how to Wire in series or parallel. I thought that was clear. My confusion is not about how the two different wiring options are implemented. I'm trying to understand how adding the extra amplifier will effect the output, if it will at all
 
lovinthehd

lovinthehd

Seriously, I have no life.
I know how to Wire in series or parallel. I thought that was clear. My confusion is not about how the two different wiring options are implemented. I'm trying to understand how adding the extra amplifier will effect the output, if it will at all
Little (based on the information provided).

ps are they single or dual voice coils?
 
T

TheEarthquakeMaker

Enthusiast
I would've appreciated a more detailed answer/explanation. But, nonetheless, that is kinda what I've assumed.
Thanks anyway.
 
lovinthehd

lovinthehd

Seriously, I have no life.
Keep in mind that it takes a doubling of power to gain 3dB spl....and with eq that changes, too.
 
T

TheEarthquakeMaker

Enthusiast
How is that information relevant to my question, how does it further my understanding ? I'm not trying to get "double" anything. I know sound is measured on a logarithmic scale, but I totally fail to see how your blanket statement is of any use in educating me ? I learnt exactly nothing from that comment. And you don't even bother to explain why. You just state it like it's a universal fact (and apparently my goal.) But it's not, doubling 5db is massively different to doubling 90db.
"It takes a doubling of power to get 3db", but at what point in the spectrum are referring too ? And again, how does that help answer my original question ? I'd love to know, I'm always down to learn, but so far, you guys are poor teachers :-(
 
lovinthehd

lovinthehd

Seriously, I have no life.
How is that information relevant to my question, how does it further my understanding ? I'm not trying to get "double" anything. I know sound is measured on a logarithmic scale, but I totally fail to see how your blanket statement is of any use in educating me ? I learnt exactly nothing from that comment. And you don't even bother to explain why. You just state it like it's a universal fact (and apparently my goal.) But it's not, doubling 5db is massively different to doubling 90db.
"It takes a doubling of power to get 3db", but at what point in the spectrum are referring too ? And again, how does that help answer my original question ? I'd love to know, I'm always down to learn, but so far, you guys are poor teachers :-(
It literally takes a doubling of power to gain 3dB spl....it's not about "doubling" 5dB or 90dB (generally it's considered somewhere between 6-10dB for a doubling in apparent volume). It's more about how it works out in your scenario....
 
T

TheEarthquakeMaker

Enthusiast
I can tell you've tried to give me a more thorough explanation than previously, and I appreciate that, sincerely.
But you're just confusing me more and more with each reply. I don't think we're even discussing my set up now, you're just stating facts, with no context.
I came to this forum because I wanted expert advice from someone far more advanced than I, but I don't think that's what I got, I got no thorough explanation, no help with my real world situation. I couldn't have possibly provided more accurate information to help you understand my query as far as I know.
I'm exactly where I started before, I know nothing more, I've learnt nothing new. Just a lot of pessimism about abstract values that don't apply to the real world.
You make me just want to give up trying to learn all this.
But thanks anyway, honestly. At least you tried, no one else even bothered. So thanks anyway. Stay safe. I'm out ✌
 
lovinthehd

lovinthehd

Seriously, I have no life.
I can tell you've tried to give me a more thorough explanation than previously, and I appreciate that, sincerely.
But you're just confusing me more and more with each reply. I don't think we're even discussing my set up now, you're just stating facts, with no context.
I came to this forum because I wanted expert advice from someone far more advanced than I, but I don't think that's what I got, I got no thorough explanation, no help with my real world situation. I couldn't have possibly provided more accurate information to help you understand my query as far as I know.
I'm exactly where I started before, I know nothing more, I've learnt nothing new. Just a lot of pessimism about abstract values that don't apply to the real world.
You make me just want to give up trying to learn all this.
But thanks anyway, honestly. At least you tried, no one else even bothered. So thanks anyway. Stay safe. I'm out ✌
I think you expect too much with limited info. This is a better question for the diy subforum, too. It's not always a cut and dried answer either. Keep learning is my best advice....
 
T

TheEarthquakeMaker

Enthusiast
I think you expect too much with limited info. This is a better question for the diy subforum, too. It's not always a cut and dried answer either. Keep learning is my best advice....
Funny you say that... I was going to say the same thing, I am asking/expecting too much. I have had a few situations where I was researching over and over, and not wrapping my head around a subject, placement of sound absorption for example. I just could not wrap my head around the explanations that I'd read. I mentioned this in a comment on an audioholics video on the subject, and I got a pretty quick reply with the most beautifully simple answer: Sit it your preferred position and have a friend hold a mirror against the wall/roof until you can see your speaker in the mirror.
Such a complex subject, explained so efficiently. I was super greatful, and I guess I was hoping someone could give me a similar, simple explanation. But I understand this is an infinitely complex subject and it won't always be possible to simplify it to that extent.
I apologise if I came across as snarky or ungreatful, I did not intend to offend anyone.
You keep mentioning "limited information" but I don't understand what more info I could possibly give you. Can you give me an example of what you mean, what info is relevant ?
And thanks for the thread suggestion, I might try asking my questions over there, obv, I'm new here :)
 
lovinthehd

lovinthehd

Seriously, I have no life.
Funny you say that... I was going to say the same thing, I am asking/expecting too much. I have had a few situations where I was researching over and over, and not wrapping my head around a subject, placement of sound absorption for example. I just could not wrap my head around the explanations that I'd read. I mentioned this in a comment on an audioholics video on the subject, and I got a pretty quick reply with the most beautifully simple answer: Sit it your preferred position and have a friend hold a mirror against the wall/roof until you can see your speaker in the mirror.
Such a complex subject, explained so efficiently. I was super greatful, and I guess I was hoping someone could give me a similar, simple explanation. But I understand this is an infinitely complex subject and it won't always be possible to simplify it to that extent.
I apologise if I came across as snarky or ungreatful, I did not intend to offend anyone.
You keep mentioning "limited information" but I don't understand what more info I could possibly give you. Can you give me an example of what you mean, what info is relevant ?
And thanks for the thread suggestion, I might try asking my questions over there, obv, I'm new here :)
Sorry, sometimes I can go off on odd tangents and/or be a bit obtuse or just be on my phone without my reading glasses and miss stuff lately :). At first I thought you had two subs too (rather than two drivers in a single sub). Sometimes I just need to reread posts :). Doubling up on the amps would be a 3dB advantage and I also was thinking of my sub amps being 2ch, forgot yours was single channel (was thinking maybe you could put a single channel on each vc). Whether that 3dB advantage is "hitting harder" I couldn't tell ya as I'm not particularly sure what you mean by that.
 
T

TheEarthquakeMaker

Enthusiast
You are correct, I have two X-W12-D4'S in one enclosure (although their chambers are isolated from one another)
And a 12" passive radiator attached to each chamber firing downward. For a total of two powered drivers, and four total 12" surfaces moving in phase. Plus yes, my plate amp is single channel, so I'm lacking some possible solutions that I might have if it were dual channel, maybe even... Bridgeable ? DAH DAH DAAAAHHH!!!
With regard to "hitting harder" I'm ashamed to admit this, but before I upgraded to plate amps and high end drivers. I had an Alpine S series from about a decade ago, running off a car amp, that I powered with a crazy cheap eBay power supply that converted 240vAC - 12vDC and introduced a poop load of huuuuummmmmmmmmm :-(
It worked, it added to the experience, but you could never really feel much. Now, I have a proper 1000w amp, a well built enclosure and 4x 12" drivers worth of surface area. It shakes you to the bone, when you turn it down you kinda feel like you just got off a roller coaster because your entire bodys been vibrating for half an hour. That's "hitting HARDER" lol.
I agree that doubling the amp should give me that 3db increase, but the problem is. And again ashamed to admit my mistakes, but I chose the wrong subs to match my amp.
The amp is limited to 4-8Ohm, and puts out 1000w at 4ohm, and 497w at 8ohm.
If I chose drivers with 2ohm DVCs I could hook each to its own amp, each pulling 1000w each. But... I have two subs with 4ohm DVCs.
This means that in parallel, both drivers can present a load of 4 Ohms Total and pull the full 1000w out of the amp. But if I wire them up individually, they can only present 2 or 8 Ohms my amp can't handle 2 ohms, which means if I add the extra amp. I go from a 4ohm system, both drivers sharing 1000w, to an 8 Ohm system each driver gets its own 497w.
If I had 2 Ohm DVCs it would be a simple add on for extra power, but working with 4 Ohm DVCs,
I'm concerned that because of the impedance shift, I wouldn't actually gain any extra power from shifting from one amp @ 4ohm 1000w into both drivers - to - 8ohm 497w into each driver.

Did that make any sense ? I feel like I rambled a bit there, sorry
 
lovinthehd

lovinthehd

Seriously, I have no life.
Thanks for the hitting harder explanation, lol.

Yeah, 2ohm DVC would be helpful now....or two 2-channel amps so you could run a channel to each coil. I have both 2 ohm DVC drivers and 4 ohm DVC drivers, prefer the flexibility the 2ohm ones provide but I also use 2 ohm capable amps so it works out. I try and use the terms driver and sub separately, two subs to me makes me think of two boxes.

Curious, why did you go with PRs instead of just porting/venting? Don't you usually need two PRs of same size as driver? Why did you go with plate amps?
 

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