3 ohm load
03-29-2009, 11:31 AM
#11
what you are saying makes sense and is technically correct. it's just not a major issue in his particular case. he's using less power in total than those subs are rated to handle.
when it comes to power distribution try thinking of it in terms of power per coil instead of power per driver. you did mention it but then you went into power per driver as well.
if he was using lots of powre and if he had different ohm coils completely then he'd actually have to worry about that sorta of problem, but in his case it's not an issue.
unless he was giving his subs close to their RMS power, the response between the two wont be noticable.
when it comes to power distribution try thinking of it in terms of power per coil instead of power per driver. you did mention it but then you went into power per driver as well.
if he was using lots of powre and if he had different ohm coils completely then he'd actually have to worry about that sorta of problem, but in his case it's not an issue.
unless he was giving his subs close to their RMS power, the response between the two wont be noticable.
03-29-2009, 07:11 PM
#12
what you are saying makes sense and is technically correct. it's just not a major issue in his particular case. he's using less power in total than those subs are rated to handle.
when it comes to power distribution try thinking of it in terms of power per coil instead of power per driver. you did mention it but then you went into power per driver as well.
if he was using lots of powre and if he had different ohm coils completely then he'd actually have to worry about that sorta of problem, but in his case it's not an issue.
unless he was giving his subs close to their RMS power, the response between the two wont be noticable.
when it comes to power distribution try thinking of it in terms of power per coil instead of power per driver. you did mention it but then you went into power per driver as well.
if he was using lots of powre and if he had different ohm coils completely then he'd actually have to worry about that sorta of problem, but in his case it's not an issue.
unless he was giving his subs close to their RMS power, the response between the two wont be noticable.
If it is not going to be an audible issue in this particular situation I will defer to your wisdom.....
....even if it does make me go 
See you in a few days.....
03-30-2009, 07:56 AM
#13
2000 Watt CAFz'r
Join Date: Jan 2001
Posts: 2,026
I'm not convinced . . .
I wonder what would be the point of the SVC? I don't think the SVC would contribute to the overall output when it will always be receiving half the power . . . it would be like a spoiler on a Neon: it might look alright, but it will serve no practical purpose.
Now if they are in a common chamber, I would think that the SVC might even begin to act somewhat like a passive radiator.
I might be convinced if he were to run one ported and the other sealed. Then the speakers would have considerably different responses. Perhaps run the SVC ported, so it will deliver more bang for the watt . . .
I don't see how staying lower than the RMS rating will somehow get the speakers to play similarly when the are receiving drastically different amounts of power.
I wonder what would be the point of the SVC? I don't think the SVC would contribute to the overall output when it will always be receiving half the power . . . it would be like a spoiler on a Neon: it might look alright, but it will serve no practical purpose.
Now if they are in a common chamber, I would think that the SVC might even begin to act somewhat like a passive radiator.
I might be convinced if he were to run one ported and the other sealed. Then the speakers would have considerably different responses. Perhaps run the SVC ported, so it will deliver more bang for the watt . . .
I don't see how staying lower than the RMS rating will somehow get the speakers to play similarly when the are receiving drastically different amounts of power.
03-30-2009, 10:19 AM
#14
I'm not convinced . . .
I wonder what would be the point of the SVC? I don't think the SVC would contribute to the overall output when it will always be receiving half the power . . . it would be like a spoiler on a Neon: it might look alright, but it will serve no practical purpose.
Now if they are in a common chamber, I would think that the SVC might even begin to act somewhat like a passive radiator.
I might be convinced if he were to run one ported and the other sealed. Then the speakers would have considerably different responses. Perhaps run the SVC ported, so it will deliver more bang for the watt . . .
I don't see how staying lower than the RMS rating will somehow get the speakers to play similarly when the are receiving drastically different amounts of power.
I wonder what would be the point of the SVC? I don't think the SVC would contribute to the overall output when it will always be receiving half the power . . . it would be like a spoiler on a Neon: it might look alright, but it will serve no practical purpose.
Now if they are in a common chamber, I would think that the SVC might even begin to act somewhat like a passive radiator.
I might be convinced if he were to run one ported and the other sealed. Then the speakers would have considerably different responses. Perhaps run the SVC ported, so it will deliver more bang for the watt . . .
I don't see how staying lower than the RMS rating will somehow get the speakers to play similarly when the are receiving drastically different amounts of power.
03-30-2009, 10:21 AM
#15
Thinking about power per coil is what 'red-flagged' this for me......twice the power to one of two drivers in a common chamber is a no-no from long ago.
If it is not going to be an audible issue in this particular situation I will defer to your wisdom.........even if it does make me go
See you in a few days.....
If it is not going to be an audible issue in this particular situation I will defer to your wisdom.....
....even if it does make me go See you in a few days.....
03-30-2009, 08:24 PM
#16
i dunno man, i always think about power per coil. thats why you see spl guys wire 6 coils to 4 amps. seems to work just fine with exessive amounts of power, i have done this without failures and i was over powering the speakers. i dont know about audiable difference between the speakers once you go past 155 db's but as far as the mechanics of it went I never had any issues. Nor was I the only one who did that.
If the difference in output could be compensated for mechanically by using a ported box for the SVC and sealed for the DVC or electrically with a strong enough amp to run at 4ohms on one channel and 2ohms on the other channel maybe that would sound better.
I would still suggest that those two woofers must be in separate chambers.....asking them to share just sounds like trouble to me......
Another $0.02 worth.....
03-31-2009, 10:56 AM
#18
2000 Watt CAFz'r
Join Date: Jan 2001
Posts: 2,026
I'm relying on part theory and part practice.
I have not done it with identical subs.
I have done it with an 8ohm SVC and a 4ohm SVC - different brand subs.
It resulted in a 2 2/3 ohm final load, and I wasn't impressed.
I found that the 8ohm did very little to add to the over-all output and it appeared to draw power away from the 4ohm as the 4ohm sub didn't move as much at the same volume on the same song. Output sounded the same, yet there were a few times that notes appeared to disappear completely with both subs running.
Perhaps part of my problem in this scenario is that I was using 2 different subs with very different performance characteristics. Yet this experience gives me confidence in the theory that similar problems will arise when the subs are seemingly identical, yet receiving different amounts of power.
I have not done it with identical subs.
I have done it with an 8ohm SVC and a 4ohm SVC - different brand subs.
It resulted in a 2 2/3 ohm final load, and I wasn't impressed.
I found that the 8ohm did very little to add to the over-all output and it appeared to draw power away from the 4ohm as the 4ohm sub didn't move as much at the same volume on the same song. Output sounded the same, yet there were a few times that notes appeared to disappear completely with both subs running.
Perhaps part of my problem in this scenario is that I was using 2 different subs with very different performance characteristics. Yet this experience gives me confidence in the theory that similar problems will arise when the subs are seemingly identical, yet receiving different amounts of power.
03-31-2009, 11:57 AM
#20
I'm relying on part theory and part practice.
I have not done it with identical subs.
I have done it with an 8ohm SVC and a 4ohm SVC - different brand subs.
It resulted in a 2 2/3 ohm final load, and I wasn't impressed.
I found that the 8ohm did very little to add to the over-all output and it appeared to draw power away from the 4ohm as the 4ohm sub didn't move as much at the same volume on the same song. Output sounded the same, yet there were a few times that notes appeared to disappear completely with both subs running.
Perhaps part of my problem in this scenario is that I was using 2 different subs with very different performance characteristics. Yet this experience gives me confidence in the theory that similar problems will arise when the subs are seemingly identical, yet receiving different amounts of power.
I have not done it with identical subs.
I have done it with an 8ohm SVC and a 4ohm SVC - different brand subs.
It resulted in a 2 2/3 ohm final load, and I wasn't impressed.
I found that the 8ohm did very little to add to the over-all output and it appeared to draw power away from the 4ohm as the 4ohm sub didn't move as much at the same volume on the same song. Output sounded the same, yet there were a few times that notes appeared to disappear completely with both subs running.
Perhaps part of my problem in this scenario is that I was using 2 different subs with very different performance characteristics. Yet this experience gives me confidence in the theory that similar problems will arise when the subs are seemingly identical, yet receiving different amounts of power.
homie, either your wiring job or your calculations were way off. you should have had a final load of 3.75 ohm. or maybe the 4 ohm sub had a bad coil. but there is no way you are supposed to get 2-2/3 ohm load with those coil configurations any way you wire them.
Last edited by Father Yuli; 03-31-2009 at 12:05 PM.
