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Behind the myth, there was some confusion and technical talk or terms that made it confusing on the other thread 8 vs 4.


In most cases the higher load coil or combined coils subs were more sensitive meaning, the extra power at the lower impedance was not going to make up the difference being 2-3 db's.

And someone said that dual coil subs, did not benefit from from wiring at a higher impedance or even if wired in series, the amp will still see 4 instead of 8 ohms, or 4 instead of 2 ohms.
Maybe I missed something, again it was a long thread with many agreeing to it, and no conclusion and having to figure it out between the lines.
 

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Am I the only one who remembers when DVC subs first came out and they were that way for "wiring options"? I tend to recall a local shop telling me that was so the subs could better match the impedance of the amplifier versus HAVING to wire both coils up in either series or parallel.

My how times have changed, lol. I could have sworn both my JL Audio and Alpine owner's manuals for my subs insisted that both coils be wired or your warranty was void.
 

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You thought you heard a difference, or the difference was because of something else.

Also, hip hop and rap sound much better with good bass, muddy, distorted bass is from a bunch of kids with terrible systems. Get your substage right and listen to Dr. Dre's 2001 and you'll see how good rap can sound.
I checked this DRe original 2001 cd today in my systems today, the funny thing is earlier i listened to the Far East movement dirty bass through a flash drive 320kbb file

To me the Dirty bass cd sounded way better, It is only about a year and months old. The Dre sounds just OK, it was extremely Flat and midrangie in my opinion, I have some Jazz CD's that have better and cleaner bass than that, electric and acoustic bass, not computer synthesized bass, computer or quality synthesized bass, Brad Mehldau Mehliana Luxe track.
Sorry to disagree, it's clean and plays clean loud but that's it
 

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Behind the myth, there was some confusion and technical talk or terms that made it confusing on the other thread 8 vs 4.
If you were referring to a specific thread on DIYMA, I was referring generically to the many discussions that discussed 8 vs 4 back in the day, many of which were in magazines and before the Internet took off. Like I said, an old mythical discussion.
 

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If you were referring to a specific thread on DIYMA, I was referring generically to the many discussions that discussed 8 vs 4 back in the day, many of which were in magazines and before the Internet took off. Like I said, an old mythical discussion.

Thanks
Just to cut to the chase then.

Lower impedance is better if the amp puts out more power and it can handle it.
8 ohms will be a bad match for most car audio amps?

In some cases, and dealing with car audio lower impedance 2-4 ohms.

For example sub X brand dual 4 coil has 90 db spl
Sub X same brand and model in dual 2ohm coil has 93 db spl
We are going to wire The D4 in parallel for the lowest resistance and the D2 in series. Only one sub will be used, simply a choice to be made between the 2 subs.

Amp puts 500W at 4 ohm and 750W at 2 ohms.

Which sub will be better for the amp assuming the rest of the specs are identical between subs power handling is 800W.
The D4 in parallel or the D2 in series?



I read the first 5 pages and I failed to read the last pages on that thread except for the last 2.
 

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I think it's just better on your electrical system if you can keep it at 4ohms or a very efficient 8ohm driver - if you have dual subs running 2 amps to keep them at 4ohms may prove to be costly


Sent from my iPhone using Tapatalk
 

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Doesn't your damping factor reduce every time you drop the impedance? Also running a amp at a easier load helps with other issues like heat, current etc... unless your trying to hit numbers a decent amp that does 500+ at 4ohms bridged is 9/10 times plenty - if you need more power rather buy a bigger amp?

Sometimes having 2 amps drive 2 subs works out better - as some amps don't double the power from 4ohms bridged to 2ohms bridged so you get more power to each driver with 2 amps and you keep your load easier

Dunno... that's my take - also depends on what you want out of your system as well I suppose


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I'am no expert so please dont take my word as reference but up untill this week after recieving an email from Helix for a question I pointed out to them I believe I along others might have the damping factor all wrong.


please view the link below which is the manual for a Helix A1 amp, notice on the last page it states damping factor adjustment for part no:22

https://130.com.ua/manuals/en/Manual-Car-amplifier-Helix-A1-Competition.pdf



if you view it it states the higher the factor the more the bass the lesser and you achieve a warmer and more balanced sound.


I was shocked when I read that and sent an email directly to Helix as I all along thought the higher the factor the more control the better everything would be but turns out thats not the case
 

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To me it don't matter if its 1 ohm load, or 2 or 4 or 8 or 16. as long as you have enough of of power going in to the sub, as long as its clean power,,, thats all it matters... but I would go with 2 ohm or 4 ohm configuration if you have the amp that could put out the juice at that ohm load.
 

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Damping factor is fake news.

Energy in the speaker's motor is stored in the inductance and in the compliance of the suspension. Damping is the speed with which the stored energy is dissipated and as far as amplifier output impedance goes, it has very little to do with the flow of current from the speaker because it's in series with the speaker's DCR and the DCR is what regulates the flow of current.

So, damping factor is crap so long as the value is greater than about 10. It's a non-spec.
 

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Damping factor is fake news.

Energy in the speaker's motor is stored in the inductance and in the compliance of the suspension. Damping is the speed with which the stored energy is dissipated and as far as amplifier output impedance goes, it has very little to do with the flow of current from the speaker because it's in series with the speaker's DCR and the DCR is what regulates the flow of current.

So, damping factor is crap so long as the value is greater than about 10. It's a non-spec.
Don't tell the old linear power fanboys this. Well you can and do but they don't care.
One of them told me to come out to an MECA event to hear some of the best cars in the circuit. He doesn't think mine can sound good since I use class D amps. At LPs headquarters. I looked at past events all over the state and they hardly have any cars breaking a 80. When they do it's just a new judge scoring higher then he should. I know Rays truck doesn't score good at all.
 

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What I have seen (in limited comparisons) is that older amplifiers 'can' sound worse at 2 ohm loads on the sub channel primarily due to their inability to store and/or supply power in loud, deep or very punchy musical passages. This may be due to a poor vehicle electrical system, the inefficiency of older class a/b design or a combination of both.
This problem doesn't seem to be as prevalent in newer class D amplifiers with moderate wattage. Probably because of their higher efficiency and lower electrical system demands.
 

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Damping factor is fake news.

Energy in the speaker's motor is stored in the inductance and in the compliance of the suspension. Damping is the speed with which the stored energy is dissipated and as far as amplifier output impedance goes, it has very little to do with the flow of current from the speaker because it's in series with the speaker's DCR and the DCR is what regulates the flow of current.

So, damping factor is crap so long as the value is greater than about 10. It's a non-spec.
At 1kHz, your assertion is correct, but at 30Hz, not so fast... >100 is desired. To claim amplifier damping factor is "fake news" only reveals how little you really understand about this issue.

From Crown Audio Amplifier Engineers; "Loudspeakers have a mind of their own. You send them a signal and they add their own twist to it. They keep on vibrating after the signal has stopped, due to inertia. That's called "ringing" or "time smearing." In other words, the speaker produces sound waves that are not part of the original signal. Suppose the incoming signal is a "tight" kick drum with a short attack and decay in its signal envelope. When the kick-drum signal stops, the speaker continues to vibrate. The cone bounces back and forth in its suspension. So that nice, snappy kick drum turns into a boomy throb. Fortunately, a power amplifier can exert control over the loudspeaker and prevent ringing. Damping is the ability of a power amplifier to control loudspeaker motion. It's measured in Damping Factor, which is load impedance divided by amplifier output impedance. High damping factor equals tight bass."

The lower the impedance of load, the less ability of an amp to exert control over the cone's movement for damping purposes, so to answer the OP's Q, depending on the amplifiers output impedance, as a general rule of thumb, a 4 ohm voice coil impedance is better for control coupled to the same amp 2 ohm or oven worse, 1 ohm. Many Class D amps these days, if the output is correctly engineered, can provide as decent a damping factor as a Class A/B, however in lower cost designs, this is overlooked. (coupling at the output filter stage) Remember the driver is just a motor in reverse, and the load on it's coupled end can exert control over it's movement. DCR = DC, impedance = AC.
 

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At 1kHz, your assertion is correct, but at 30Hz, not so fast... >100 is desired. To claim amplifier damping factor is "fake news" only reveals how little you really understand about this issue.
Bold move calling out Andy, but +sub for the reply. :)

I appreciate a good discussion with opposing viewpoints.
 

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Bold move calling out Andy, but +sub for the reply. :)

I appreciate a good discussion with opposing viewpoints.
I was at Altec-Lansing back before Mark IV Industries (owned Altec, EV, Dynacord, University Sound, Telex...) sold it off to the Chinese and dropped the Professional lines, and it doesn't take long with a pulse tone to an A2 VOT cabinet in the anechoic chamber to prove up the exact same thing Crown engineers stated.
 

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I was at Altec-Lansing back before Mark IV Industries (owned Altec, EV, Dynacord, University Sound, Telex...) sold it off to the Chinese and dropped the Professional lines, and it doesn't take long with a pulse tone to an A2 cabinet in the anechoic chamber to prove up the exact same thing Crown engineers stated.
Nice. To be fair I think Andy was making the point that it's not enough of a change to make a audible difference either way. However I did the same research and ended up opting for a 4-ohm subwoofer myself based on the same reasoning you posted above. I'm hoping that we'll get to see some data-driven debates on this topic.
 
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