Page 3 of 8 FirstFirst 12345678 LastLast
Results 21 to 30 of 77
Like Tree1Likes

Thread: Cap or not to cap

  1. #21
    Constant Bitrate
    Join Date
    Jan 2008
    Location
    Wellsboro, Pennsylvania, United States
    Posts
    163
    Info on my amps...

    Speaker amp - Kenwood x600f
    http://www.crutchfield.com/S-HIzfKx7...lon-X600F.html
    http://www.kenwoodusa.com/Car_Entert...tainment/X600F
    RATED OUTPUT POWER (14.4V):
    • 100W RMS x 4 @ 4Ω
    • (20Hz-20kHz @ 0.05%THD)
    • 150W RMS x 4 @ 2Ω
    • (1kHz @ 0.5% THD)
    • 300W RMS x 2 @ 2Ω (Bridged)
    • (1kHz @ 0.5% THD)


    • RMS POWER OUTPUT (CEA-2006)
    • 100W RMS x 4
    • (RMS @ 4Ω, 1% THD+N)
    • 85dBa Signal-To-Noise Ratio


    BUILT-IN CROSSOVER CONTROL:
    • Variable High-Pass Filter: 50Hz-200Hz (-12dB/oct)
    • Variable Low-Pass Filter: 50Hz-200Hz (-12dB/oct)

    ------------------------------------------------------

    Sub Amp - Rockford
    http://www.rockfordfosgate.com/produ...ails/p1000x1bd



    Rated Power
    (RMS Continuous Power): 300 Watts x 1 @ 4-Ohm
    500 Watts x 1 @ 2-Ohm
    1000 Watts x 1 @ 1-Ohm


    Total Power
    (Sum of Rated Power): 1000 Watts RMS


    Dynamic Power
    (PVC/PowerCubeŽ Measurement): 491 Watts x 1 @ 4-Ohms
    874 Watts x 1 @ 2-Ohms
    1,430 Watts x 1 @ 1-Ohm


    Bridgeable: No


    Efficiency (average): 86% @ 4-Ohm


    Crossover Controls: Low-Pass (LP): 50-250Hz @ 12dB/octave Butterworth
    Infrasonic Filter (IF): 28Hz @ 12dB/Octave Butterworth

  2. #22
    Maximum Bitrate
    Join Date
    May 2012
    Location
    Grandville, MI
    Posts
    600
    Without looking at the numbers...

    The design looks good except one thing...

    You need to fuse all items coming out of the power distribution block. You can get a distribution block with fused outputs and put a fuse on each one. As designed you can burn up your amplifier wire to the speakers long before you will blow the 200amp fuse.

    The fuses in the amplifiers are to protect the amplifiers. The fuses on the power lines is to protect the wires.

  3. #23
    Constant Bitrate
    Join Date
    Jan 2008
    Location
    Wellsboro, Pennsylvania, United States
    Posts
    163
    Quote Originally Posted by redheadedrod View Post
    Without looking at the numbers...

    The design looks good except one thing...

    You need to fuse all items coming out of the power distribution block. You can get a distribution block with fused outputs and put a fuse on each one. As designed you can burn up your amplifier wire to the speakers long before you will blow the 200amp fuse.

    The fuses in the amplifiers are to protect the amplifiers. The fuses on the power lines is to protect the wires.
    Poop on a stick...Sorry I just realized I forgot to put the second fuse in the picture...aside from that what do you think? After all this is installed and up and going...I plan on working on my carputer. I have a couple potential computers to be used...notebooks and all I have to do is get the power supply for it and a screen.

  4. #24
    Raw Wave
    Join Date
    Nov 2009
    Posts
    2,119
    Pity you can't use 2G to the amps, then you could just have the main 200A fuse (else lower the main fuse's rating).
    IMO assuming the sub amp has its own fuse (100A?), then you are merely protecting the d-block to amp cables from short circuit and a master 200A should be ok for 4G.
    (Each series fuse & DB & connection adds to power path resistance hence arguably adding the requirement for a 2nd battery else a cap. Those that want to ensure cranking independence if using the amps when not charging add a 2nd battery and isolator.)

    But I'd suggest using a body/chassis GND from the amps to the main battery & alternator. That may even negate the need for the dedicated GND wiring.

  5. #25
    Constant Bitrate
    Join Date
    Jan 2008
    Location
    Wellsboro, Pennsylvania, United States
    Posts
    163
    Quote Originally Posted by OldSpark View Post
    Pity you can't use 2G to the amps, then you could just have the main 200A fuse (else lower the main fuse's rating).
    IMO assuming the sub amp has its own fuse (100A?), then you are merely protecting the d-block to amp cables from short circuit and a master 200A should be ok for 4G.
    (Each series fuse & DB & connection adds to power path resistance hence arguably adding the requirement for a 2nd battery else a cap. Those that want to ensure cranking independence if using the amps when not charging add a 2nd battery and isolator.)

    But I'd suggest using a body/chassis GND from the amps to the main battery & alternator. That may even negate the need for the dedicated GND wiring.
    So your saying o run another ground for each amp to the chassis also?

  6. #26
    Constant Bitrate
    Join Date
    Jan 2008
    Location
    Wellsboro, Pennsylvania, United States
    Posts
    163
    I do have in the works...bigger alt., upgrading the big 3 and a second battery...just not right now

  7. #27
    Maximum Bitrate RAWPWR's Avatar
    Join Date
    May 2007
    Posts
    616
    Oldspark,.....I guess they didn't get your memo. lol

    Attached Images Attached Images  

  8. #28
    Constant Bitrate FockMasterDan's Avatar
    Join Date
    May 2008
    Location
    Westerville, Ohio
    Posts
    140
    Quote Originally Posted by OldSpark View Post
    Pity you can't use 2G to the amps, then you could just have the main 200A fuse (else lower the main fuse's rating).
    IMO assuming the sub amp has its own fuse (100A?), then you are merely protecting the d-block to amp cables from short circuit and a master 200A should be ok for 4G.
    (Each series fuse & DB & connection adds to power path resistance hence arguably adding the requirement for a 2nd battery else a cap. Those that want to ensure cranking independence if using the amps when not charging add a 2nd battery and isolator.)

    But I'd suggest using a body/chassis GND from the amps to the main battery & alternator. That may even negate the need for the dedicated GND wiring.
    With good connections the amount of resistance you add is going to be minimal. I'd be curious to test all the points in my system and actually measure it out.

    I'm personally a fan of using a circuit breaker for a master fuse for two reasons. One is obviously if it blows you can just flip it back on and not be out of commission. The other is it makes it really easy to work on the electronics, just flip the breaker and you don't have to remove any connections. I have to use a breaker because my main battery is in the trunk and it protects that line. It would be awful to get stranded on the side of the road because of a fuse.

    One thing to keep in mind for audio wiring is that if possible ground all components in the system to the same point (for the sake of noise). With my battery in the trunk I'm able to route everything directly to the battery in short runs, but I understand most people don't have that option.
    Computer is in the car, but in a very "raw" install right now.

    Worklog - here

  9. #29
    Raw Wave
    Join Date
    Nov 2009
    Posts
    2,119
    Quote Originally Posted by DracoPCGuy View Post
    So your saying o run another ground for each amp to the chassis also?
    What I was really saying was to use chassis INSTEAD of the GND cable back to the batt/alt GND. In my experience chassis have always had lower resistance than cables, but some installers ground to body panels which are not of adequate gauge or inter-panel/chassis bonding else are non-metallic in which case a dedicated GND cable is required.

    But even if a GND cable is used, paralleling a chassis GND path can only lower the total GND resistance. And it should not cause problems (eg, GND loops).


    RAWPWR - that pic reminds me of the original Richard Clark cap banks. (Need I say more?)


    I agree with what FockMasterDan says about connection resistances being minimal, but when audiophiles go on about 3-7 milli-Ohm ESR differences between AGM and equivalent wet-cell batteries, they may not be that insignificant. But that is another area full of contradictions - high peak SPL competitors are effectively arguing for HIGHER resistances to achieve higher peak SPLs.
    In DracoPCGuy's case, assume a 20' run of 0G (+12V & GND) - that's 1.6mR (milli-Ohm) in itself. Each fuse adds 4 contact resistances (cable to fuse holder; holder to fuse) plus the fuse resistance. The dblock adds 2 more contact/join resistances (in & out) but I'll assume the dblock bus itself has negligible resistance.
    Whilst there is also the battery post to terminal (connector) resistance plus its joint resistance to the cable, and the amp connector joint resistance to cables, they are an evil necessity that can be minimised, but not eliminated.
    My point is that all those resistances add up and - even without dblocks and extra fuses - may often make "rated" battery ESRs (valid only for fully charged and good/new batteries) insignificant. But the discussions continue on and on.

    I also agree with the use of CBs instead of fuses for the same reasons. You can carry spare fuses, but then a CB may be cheaper than a few fuses. [ For dual-batteries that are not for big loads (eg, for fridges or PCs, NOT winches or audio), I recommend (insist!) on self-resetting circuit breakers for the inter-battery link. I have a 50A self resetting CB on each end of my dual-battery interlink which only has a MAXIMUM 2nd battery load of 2.5A (a 40L fridge). I got sick of being unaware of 30A fuses that would occasionally blow... ]

    Of course resistance sensitive audiophiles should be using magnetic breakers since they have no resistance other than their (relay) contact resistance.
    And if they have a dual battery setup, the isolator is already one such relay - just add over-current sensing to de-energise the battery isolator's relay/contactor. The other battery-end protection could be another current sensing breaker/relay, else a CB or fuse.

    But apart from better cranking security with dual battery set ups, a second battery collocated with the amp(s) means the battery interlink merely has to supply the max power required (RMS!) plus adequate recharge current. (And 13.8-14.4V at least occasionally.) The surge aspect can be localised to the 2nd battery to amp(s) +12V and ground cabling (eg, a short else double runs or bigger gauge).


    As to why voltage dips for big amps is an issue beats me. After all, they use SMPS supplies and hence the voltage should not matter. (Yes, I know some amp specs read as if amps are purely resistive loads. And no, I still haven't deciphered my sample Kicker SMPS.)
    But that brings me to yet another thorn for cap adders. As redheadedrod wrote, amps have their own caps, but they are on the OUTPUT side of the PSU/SMPS, not the input/supply side. Hence cappers should be adding pairs of 35V or 50V caps etc, not 12V caps! (That is a cap proposal I could support, but that proposal has yet to hit the masses LOL.)

  10. #30
    Constant Bitrate FockMasterDan's Avatar
    Join Date
    May 2008
    Location
    Westerville, Ohio
    Posts
    140
    Quote Originally Posted by OldSpark View Post
    What I was really saying was to use chassis INSTEAD of the GND cable back to the batt/alt GND. In my experience chassis have always had lower resistance than cables, but some installers ground to body panels which are not of adequate gauge or inter-panel/chassis bonding else are non-metallic in which case a dedicated GND cable is required.

    But even if a GND cable is used, paralleling a chassis GND path can only lower the total GND resistance. And it should not cause problems (eg, GND loops).


    RAWPWR - that pic reminds me of the original Richard Clark cap banks. (Need I say more?)


    I agree with what FockMasterDan says about connection resistances being minimal, but when audiophiles go on about 3-7 milli-Ohm ESR differences between AGM and equivalent wet-cell batteries, they may not be that insignificant. But that is another area full of contradictions - high peak SPL competitors are effectively arguing for HIGHER resistances to achieve higher peak SPLs.
    In DracoPCGuy's case, assume a 20' run of 0G (+12V & GND) - that's 1.6mR (milli-Ohm) in itself. Each fuse adds 4 contact resistances (cable to fuse holder; holder to fuse) plus the fuse resistance. The dblock adds 2 more contact/join resistances (in & out) but I'll assume the dblock bus itself has negligible resistance.
    Whilst there is also the battery post to terminal (connector) resistance plus its joint resistance to the cable, and the amp connector joint resistance to cables, they are an evil necessity that can be minimised, but not eliminated.
    My point is that all those resistances add up and - even without dblocks and extra fuses - may often make "rated" battery ESRs (valid only for fully charged and good/new batteries) insignificant. But the discussions continue on and on.

    I also agree with the use of CBs instead of fuses for the same reasons. You can carry spare fuses, but then a CB may be cheaper than a few fuses. [ For dual-batteries that are not for big loads (eg, for fridges or PCs, NOT winches or audio), I recommend (insist!) on self-resetting circuit breakers for the inter-battery link. I have a 50A self resetting CB on each end of my dual-battery interlink which only has a MAXIMUM 2nd battery load of 2.5A (a 40L fridge). I got sick of being unaware of 30A fuses that would occasionally blow... ]

    Of course resistance sensitive audiophiles should be using magnetic breakers since they have no resistance other than their (relay) contact resistance.
    And if they have a dual battery setup, the isolator is already one such relay - just add over-current sensing to de-energise the battery isolator's relay/contactor. The other battery-end protection could be another current sensing breaker/relay, else a CB or fuse.

    But apart from better cranking security with dual battery set ups, a second battery collocated with the amp(s) means the battery interlink merely has to supply the max power required (RMS!) plus adequate recharge current. (And 13.8-14.4V at least occasionally.) The surge aspect can be localised to the 2nd battery to amp(s) +12V and ground cabling (eg, a short else double runs or bigger gauge).


    As to why voltage dips for big amps is an issue beats me. After all, they use SMPS supplies and hence the voltage should not matter. (Yes, I know some amp specs read as if amps are purely resistive loads. And no, I still haven't deciphered my sample Kicker SMPS.)
    But that brings me to yet another thorn for cap adders. As redheadedrod wrote, amps have their own caps, but they are on the OUTPUT side of the PSU/SMPS, not the input/supply side. Hence cappers should be adding pairs of 35V or 50V caps etc, not 12V caps! (That is a cap proposal I could support, but that proposal has yet to hit the masses LOL.)
    A lot of interesting information there. I'm not a full on audiophile at this point, but pretty far on my way there as far as my budget will allow. I know there are raging debates on the significance of certain factors where half the people insist it matters and the other half say it makes no difference. I have a feeling arguing the resistance here is one of those areas. You mention yourself that is an area that is full of contradictions. All I can say is that I'm confident that unless we're talking about several thousands of dollars of amps and speakers that isn't the weakest point of the system. I have plenty to upgrade and improve before I worry about minimizing connection points and I'm already at the thousands of dollars point.

    I don't know a whole lot about the circuitry for SMPS or what my amps use. I haven't had the chance to dig in that deep in that area since I know I'm already pretty tapped out on my amp budget (one more to upgrade with the sub amp still).

    I will question how much it matters which side of the PS the caps are on in an amp design. This is obvisouly based purely on theory since I just admitted I don't know the circuitry but here is my perspective. The purpose here of using capacitors is to allow the peak load demands of a sound system to be satisfied by storing up energy available to discharge when needed. If our amp needs to output the peak load and can use the capacitors to help with the power demands from the power supply, then it should have essentially the same effect as putting capacitors before the power supply. The only real difference is that we're making life easier on the power supply by using capacitors after it, so why would you put them before instead?

    If we were using a cap to deal with voltage fluctuations from the supply side of the circuit - the car's alternator and batteries, then I think it would make more sense to have one before. Since we're always talking in car audio about caps being needed for the output demands of the sound system I don't think that's as relevant.
    Last edited by FockMasterDan; 07-18-2013 at 04:35 AM.
    Computer is in the car, but in a very "raw" install right now.

    Worklog - here

Page 3 of 8 FirstFirst 12345678 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •