I sent a tech question to JBL and asked if the BP600.1 was stable at 1 ohm... they say no... but they also talk about wiring 2 and the calculations do not seem right....
~~~~~~~~Good morning and thank you for your inquiry. While the BP600.1 can handle impedances down to a 1 ohm load, it is actually stable to 2 ohms; anything lower than the 2 ohm rating may/can cause the amplifier to shut down, at the “right” conditions. If you are using a pair of subwoofers that have dual 2 ohm voice coils, each sub has the option of being 4 ohms (series) or 1 ohm (parallel). If you wire the subs in series (4 ohms each), then connect both to the amp, the amp will see a 2 ohm load, and will produce close to the maximum output.
If you wire each subwoofer in parallel (1 ohm each), and connect these to the amp, there is a good chance your amp will shut down, as you are now feeding an impedance below 1 ohm into the amplifier. This connection can eventually cause the amp to fail completely, as you are forcing the amp to “clip”. I would suggest using the first option, as this would still give you the desired amount of power, without causing any damage to the amp.
Thanks again for your e-mail, and please let us know if you have any other questions.
I hope this helps.
Sincerely,
Mark Tirotta
Internet Support Specialist
CAN SOMEBODY please tell me if im wrong? im just trying to figure out if my 2 12' 4 ohm DVC kicker cvrs wired in parallel is a 1 ohm load and can damage my amp or its 2 ohm load?
if they are a 1 ohm load and 2 12' DVC 2 ohms would pair up better w/ the jbl into a 2 ohm load let me know (i can easily swap mine for 2 ohm versions only paying 10 bux a speaker...)
Replies (15)
alanjlamore on 04/13/2005 14:33:03
It looks like he's giving examples showing 2, 2ohm dual voice coil subs and he's correct if that's the kind of subs you have.
If what you have are 2, 4ohm single voice coil subs, then you'd just hook them up in parallel to get your 2 ohm load. The thing with those JBL amps is that it has what looks like 2 channels on the amp. This is just for easier wiring and they're connected in parallel inside the amp (from what I understand). So with 2 sigle voice coil 4ohm subs, you'd hook each sub up to it's own input on the amp and they'd be wired in parallel, with a 2ohm load giving you the 600W rms to the subs (300 each).
It all depends on how many voice coils your sub has (1 or 2) and how much resistance each voice coil is (4ohm or 2ohm).
ssallstar598 on 04/13/2005 14:34:00
they are DVC 4 ohms Kicker CVRs
lessismorespl on 04/13/2005 14:36:35
Are the CVR's DVC or SVC, if they are single 4ohm voice coils, wiring both of them in parallel to the amp will create an impedance of 2ohms, if they are Dual 4ohm, wiring the coils in parallel creates 2 2ohm subs, which would then be a 1ohm impedance to the amp, you would have to wire the coils in series, then wire the subs in parallel to the amp which would then be a 4ohm impedance. If you go to http://www.bcae1.com and look on the right sidebar menu for series/parallel basics, it will explain it more in depth, there is also an advanced series/parallel on this site, as well as a complete and detailed description of speaker impedances.
alanjlamore on 04/13/2005 14:38:50
then they could be wired in series/parallel which would give you a total of 4ohms, or parallel/parallel which would give you 1ohm.
I have heard before that this amp can take 1ohm, but still puts out the same as if it had 2 ohms. I don't know for sure, but someone else here would know. That's a pretty popular amp here.
The only way I can think of hooking the 2 subs up would be with 4ohms or 1ohm.
ssallstar598 on 04/13/2005 14:40:43
they are DVC 4 ohm kicker CVR subwoofers
so that means i can only get a 1ohm load (parallel/parallel) and a 4 ohm load (series/parallel)... and the DVC 2ohm Kicker CVR subwoofers would wire into a 2 ohm load right? (series/parallel)
alanjlamore on 04/13/2005 14:45:06
right, if you had 2of the 2ohm DVCs then you could get a 2ohm load by wiring in series/parallel.
lessismorespl on 04/13/2005 15:02:34
yes, you answered your own ?
swez on 04/13/2005 17:58:41
I read this as a "fair warning" to JBL users. The amp is rated for 2 ohm loads. However, it has been proven to handle 1 ohm loads if ppl would be intelligent in their gain settings and bass boost usage. Since the amp has no internal fans (I think?) the case and heat sinks have to work harder to cool the amp. If the amp gets too hot, it will go into thermal protect mode.
If you have the option to change to a pair of 2+2 DVC's, that might be a pretty good idea. Why? easier on the amp and compatible w/ >80% of the Class D amps on the market today. To get a 2 ohm lead here, just wire each sub up in series for a 4 ohm load. Wire 1 sub to each output lug set on amp. Viola... 2 ohms
Swez
ssallstar598 on 04/13/2005 19:46:04
http://img8.exs.cx/my.php?loc=img8&image=2dvcseriesvcparallelsubs0gh.jpg
so like that correct?
and no the JBL does not have a fan
ALSO since the JBL has 4 input channels (manual says if you put all 4 its non fading and if you dont put all 4 its regular fading bass) (RCA inputs) (2 front L/R and 2 rear L/R) could i run 1 RCA cable and 2 Y adaptors 1F2M?
heres a pic of the y adapter http://knukonceptz.com/productDetail.cfm?prodID=KLA-1F2M
UKinstaller on 04/13/2005 21:14:10
i have run two seperate JBL BP600.1 amps for two different cars and both of them overheated at 1 ohm. i don't recommend it, but trying it shouldn't hurt anything too bad. if it overheats, then rewire it.
-UK
Victor on 04/14/2005 03:24:52
Ok.. here is what i have seen and experienced with the JBL 600.1..
It runs very safe and cool at 2 ohms. But there is nothing but overheating and shutting down due to the thermal protection circuitry at 1 ohm loads.
I had mentioned before , and i am doing it again.
We here usually make enclosures for subs, kick panels and door panels for the speakers thinking that it is necessary for good sound.
Then why dont we understand and make the effort to make a fancooled amp rack to safe guard the amps we use and get the best out of them.
after repeated shutdowns by the 600.1 due to over heating, i suggested my friend to make an amp rack with 2 fans in the push pull configuration, also helped him make it. And he has been using that amp at 1 ohm since a year now and has faced no problems.
If we can make effort and fabricate complex enclosures for our subs, we can surely make a simple amp casing or an amp rack to ensure their optimum performance..
Dunno how many wud agree with me, cause most newbies dont wanna get into such kinda stuff, but atleast the experienced guys shud not skip this step out of laziness..
comments...??
Victor...
swez on 04/14/2005 09:57:46
Agreed, all electronic amplifiers generate heat. The worst enemy in any high powered electronic device or component IS HEAT!
Many of the newer amps either use larger heat sinks that are integrated into the case or add cooling fans. If we tend to push our gear to a point of thermal cutoff protection, we need to manage the heat buildup by cooling the amp casing from ouside the unit.
Also, installing an amp is a critical decision as well. Small sections under the seats can contain the heat as there is no way to move air past them well enough to cool them w/o help of a fan or fresh air ducts.
Finally, most amps can cool themselves adequately when mounted flat or vertical positions with the heat sinks pointed up. The worst way to install an amp is in the upside down position on a parcel shelf. The heat gets trapped in the sinks and casing and can easily build up excess heat that way. If using that install method, by all means, either install push/pull fans and a shroud or move the amp to a new location.
Swez
Bigeazy4387 on 04/14/2005 11:24:25
that amp will hold 1ohm and it will hold it for a while. i just moved and the guy i just traded my 18"compvrs for 3 compvr 12" . he has a jbl600.1 we ran it in mono with the amp in non-fading mode and it came very close to blowing the 12" compvrs. when i say close it almost tore the surround so what im sayin is the amp can hold it the speakers may not if you dont watch how you have your gains and bass boost adjusted. the 2 12's we almost blew are in a sealed 5.0cu.ft. box. those 2 are the 2003 model i have 1 more 2005 model but it is not hooked up
ssallstar598 on 04/14/2005 18:19:12
swez - sounds like a good idea on the cooling fans
1 question - my friend has a ported box w/ his amp mounted on his flip down backseat and when its flipped up its about 4 inches away from one of the ports and the air is getting blown onto the amp i know the cooling from the air blowing out the port is a good thing but is the fact that the port puts out bass and vibrates the amp a bad thing?
swez on 04/15/2005 19:54:43
Most newer amps can take a fair degree of vibration and survive it. Vent cooling from a ported box may not be a good idea in high powered sub applications.
Why? The vented air is also heated by the voice coil(s) and may actually be warmer than ambient air surrounding the amp. Also, the air being pushed out of the port is most efficiently moved near the port
tuned frequency. If you friend is having trouble cooling the amp, fans make more sense.
Lastly, if you friend has this sub box loaded in a sedan or hatchback, he may find the bass sounds better (fuller) when the subs are pointed to the rear bumper.
Good luck,
Swez
~~~~~~~~Good morning and thank you for your inquiry. While the BP600.1 can handle impedances down to a 1 ohm load, it is actually stable to 2 ohms; anything lower than the 2 ohm rating may/can cause the amplifier to shut down, at the “right” conditions. If you are using a pair of subwoofers that have dual 2 ohm voice coils, each sub has the option of being 4 ohms (series) or 1 ohm (parallel). If you wire the subs in series (4 ohms each), then connect both to the amp, the amp will see a 2 ohm load, and will produce close to the maximum output.
If you wire each subwoofer in parallel (1 ohm each), and connect these to the amp, there is a good chance your amp will shut down, as you are now feeding an impedance below 1 ohm into the amplifier. This connection can eventually cause the amp to fail completely, as you are forcing the amp to “clip”. I would suggest using the first option, as this would still give you the desired amount of power, without causing any damage to the amp.
Thanks again for your e-mail, and please let us know if you have any other questions.
I hope this helps.
Sincerely,
Mark Tirotta
Internet Support Specialist
CAN SOMEBODY please tell me if im wrong? im just trying to figure out if my 2 12' 4 ohm DVC kicker cvrs wired in parallel is a 1 ohm load and can damage my amp or its 2 ohm load?
if they are a 1 ohm load and 2 12' DVC 2 ohms would pair up better w/ the jbl into a 2 ohm load let me know (i can easily swap mine for 2 ohm versions only paying 10 bux a speaker...)
Replies (15)
alanjlamore on 04/13/2005 14:33:03
It looks like he's giving examples showing 2, 2ohm dual voice coil subs and he's correct if that's the kind of subs you have.
If what you have are 2, 4ohm single voice coil subs, then you'd just hook them up in parallel to get your 2 ohm load. The thing with those JBL amps is that it has what looks like 2 channels on the amp. This is just for easier wiring and they're connected in parallel inside the amp (from what I understand). So with 2 sigle voice coil 4ohm subs, you'd hook each sub up to it's own input on the amp and they'd be wired in parallel, with a 2ohm load giving you the 600W rms to the subs (300 each).
It all depends on how many voice coils your sub has (1 or 2) and how much resistance each voice coil is (4ohm or 2ohm).
ssallstar598 on 04/13/2005 14:34:00
they are DVC 4 ohms Kicker CVRs
lessismorespl on 04/13/2005 14:36:35
Are the CVR's DVC or SVC, if they are single 4ohm voice coils, wiring both of them in parallel to the amp will create an impedance of 2ohms, if they are Dual 4ohm, wiring the coils in parallel creates 2 2ohm subs, which would then be a 1ohm impedance to the amp, you would have to wire the coils in series, then wire the subs in parallel to the amp which would then be a 4ohm impedance. If you go to http://www.bcae1.com and look on the right sidebar menu for series/parallel basics, it will explain it more in depth, there is also an advanced series/parallel on this site, as well as a complete and detailed description of speaker impedances.
alanjlamore on 04/13/2005 14:38:50
then they could be wired in series/parallel which would give you a total of 4ohms, or parallel/parallel which would give you 1ohm.
I have heard before that this amp can take 1ohm, but still puts out the same as if it had 2 ohms. I don't know for sure, but someone else here would know. That's a pretty popular amp here.
The only way I can think of hooking the 2 subs up would be with 4ohms or 1ohm.
ssallstar598 on 04/13/2005 14:40:43
they are DVC 4 ohm kicker CVR subwoofers
so that means i can only get a 1ohm load (parallel/parallel) and a 4 ohm load (series/parallel)... and the DVC 2ohm Kicker CVR subwoofers would wire into a 2 ohm load right? (series/parallel)
alanjlamore on 04/13/2005 14:45:06
right, if you had 2of the 2ohm DVCs then you could get a 2ohm load by wiring in series/parallel.
lessismorespl on 04/13/2005 15:02:34
yes, you answered your own ?
swez on 04/13/2005 17:58:41
I read this as a "fair warning" to JBL users. The amp is rated for 2 ohm loads. However, it has been proven to handle 1 ohm loads if ppl would be intelligent in their gain settings and bass boost usage. Since the amp has no internal fans (I think?) the case and heat sinks have to work harder to cool the amp. If the amp gets too hot, it will go into thermal protect mode.
If you have the option to change to a pair of 2+2 DVC's, that might be a pretty good idea. Why? easier on the amp and compatible w/ >80% of the Class D amps on the market today. To get a 2 ohm lead here, just wire each sub up in series for a 4 ohm load. Wire 1 sub to each output lug set on amp. Viola... 2 ohms
Swez
ssallstar598 on 04/13/2005 19:46:04
http://img8.exs.cx/my.php?loc=img8&image=2dvcseriesvcparallelsubs0gh.jpg
so like that correct?
and no the JBL does not have a fan
ALSO since the JBL has 4 input channels (manual says if you put all 4 its non fading and if you dont put all 4 its regular fading bass) (RCA inputs) (2 front L/R and 2 rear L/R) could i run 1 RCA cable and 2 Y adaptors 1F2M?
heres a pic of the y adapter http://knukonceptz.com/productDetail.cfm?prodID=KLA-1F2M
UKinstaller on 04/13/2005 21:14:10
i have run two seperate JBL BP600.1 amps for two different cars and both of them overheated at 1 ohm. i don't recommend it, but trying it shouldn't hurt anything too bad. if it overheats, then rewire it.
-UK
Victor on 04/14/2005 03:24:52
Ok.. here is what i have seen and experienced with the JBL 600.1..
It runs very safe and cool at 2 ohms. But there is nothing but overheating and shutting down due to the thermal protection circuitry at 1 ohm loads.
I had mentioned before , and i am doing it again.
We here usually make enclosures for subs, kick panels and door panels for the speakers thinking that it is necessary for good sound.
Then why dont we understand and make the effort to make a fancooled amp rack to safe guard the amps we use and get the best out of them.
after repeated shutdowns by the 600.1 due to over heating, i suggested my friend to make an amp rack with 2 fans in the push pull configuration, also helped him make it. And he has been using that amp at 1 ohm since a year now and has faced no problems.
If we can make effort and fabricate complex enclosures for our subs, we can surely make a simple amp casing or an amp rack to ensure their optimum performance..
Dunno how many wud agree with me, cause most newbies dont wanna get into such kinda stuff, but atleast the experienced guys shud not skip this step out of laziness..
comments...??
Victor...
swez on 04/14/2005 09:57:46
Agreed, all electronic amplifiers generate heat. The worst enemy in any high powered electronic device or component IS HEAT!
Many of the newer amps either use larger heat sinks that are integrated into the case or add cooling fans. If we tend to push our gear to a point of thermal cutoff protection, we need to manage the heat buildup by cooling the amp casing from ouside the unit.
Also, installing an amp is a critical decision as well. Small sections under the seats can contain the heat as there is no way to move air past them well enough to cool them w/o help of a fan or fresh air ducts.
Finally, most amps can cool themselves adequately when mounted flat or vertical positions with the heat sinks pointed up. The worst way to install an amp is in the upside down position on a parcel shelf. The heat gets trapped in the sinks and casing and can easily build up excess heat that way. If using that install method, by all means, either install push/pull fans and a shroud or move the amp to a new location.
Swez
Bigeazy4387 on 04/14/2005 11:24:25
that amp will hold 1ohm and it will hold it for a while. i just moved and the guy i just traded my 18"compvrs for 3 compvr 12" . he has a jbl600.1 we ran it in mono with the amp in non-fading mode and it came very close to blowing the 12" compvrs. when i say close it almost tore the surround so what im sayin is the amp can hold it the speakers may not if you dont watch how you have your gains and bass boost adjusted. the 2 12's we almost blew are in a sealed 5.0cu.ft. box. those 2 are the 2003 model i have 1 more 2005 model but it is not hooked up
ssallstar598 on 04/14/2005 18:19:12
swez - sounds like a good idea on the cooling fans
1 question - my friend has a ported box w/ his amp mounted on his flip down backseat and when its flipped up its about 4 inches away from one of the ports and the air is getting blown onto the amp i know the cooling from the air blowing out the port is a good thing but is the fact that the port puts out bass and vibrates the amp a bad thing?
swez on 04/15/2005 19:54:43
Most newer amps can take a fair degree of vibration and survive it. Vent cooling from a ported box may not be a good idea in high powered sub applications.
Why? The vented air is also heated by the voice coil(s) and may actually be warmer than ambient air surrounding the amp. Also, the air being pushed out of the port is most efficiently moved near the port
tuned frequency. If you friend is having trouble cooling the amp, fans make more sense.
Lastly, if you friend has this sub box loaded in a sedan or hatchback, he may find the bass sounds better (fuller) when the subs are pointed to the rear bumper.
Good luck,
Swez
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