pot knobs on amps

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knightrider358
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Location: Virginia, Near D.C.

pot knobs on amps

Post by knightrider358 »

Ok guys before I did my install recently when I got my black ZX450 and Ti600.2 I took the covers off and cleaned the boards and all. While I had the covers off I noticed a couple of small pot knobs on the boards of each amp jus wondering what are these for exactly? Ive seen them before on allot of other amps before but never figured out what they are for. Any replays would be greatly appreciated thanx in advance
Current 1 of 2 current installs

HU-Alpine IVA-D310
DSP-PXA-H701
Comps-JL ZR 650
Sub-3 JL 10w6v1ae's sealed
Highs amp-MS275
Mids amp-MS2125
Subs amp-MS2250TA
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fuzzysnuggleduck
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Post by fuzzysnuggleduck »

Are you maybe talking about the bias pots?
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knightrider358
Posts: 1318
Joined: Mon May 04, 2009 3:37 am
Location: Virginia, Near D.C.

Post by knightrider358 »

prob what do they do
Current 1 of 2 current installs

HU-Alpine IVA-D310
DSP-PXA-H701
Comps-JL ZR 650
Sub-3 JL 10w6v1ae's sealed
Highs amp-MS275
Mids amp-MS2125
Subs amp-MS2250TA
Thumper88
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Joined: Tue Feb 20, 2007 9:03 pm
Location: Michigan

Post by Thumper88 »

BCAE1.COM wrote:Many times, there is a bias adjustment potentiometer. It allows you to set the bias/idle current of the output transistors. If the bias is set too high, the outputs will run too hot and be more likely to fail. If set too low, the output could be distorted. There have been many instances where someone has gone into an amplifier and turned the bias pot up (thinking that they were increasing the power output of the amp). This caused the amp to fail. Unless a potentiometer is accessible from the outside of the amplifier, you should not turn it unless you know what it is. Having the bias current set too high is like having the idle setting on your car's engine set to 3000 RPMs instead of 750 RPMs.
ttocs
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Post by ttocs »

F-it, crank it up and see what happens....
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knightrider358
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Joined: Mon May 04, 2009 3:37 am
Location: Virginia, Near D.C.

Post by knightrider358 »

ya'll are crazy I aint touchin those unless I see fact if they are my idle controll
Current 1 of 2 current installs

HU-Alpine IVA-D310
DSP-PXA-H701
Comps-JL ZR 650
Sub-3 JL 10w6v1ae's sealed
Highs amp-MS275
Mids amp-MS2125
Subs amp-MS2250TA
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Jacampb2
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Location: Beaverton 48612

Post by Jacampb2 »

The two pots at the top left hand side of the board are right and left bias control. The pot at the lower middle right, just to the left of the power supply riser card, is the pot that adjusts the current regulation of the amps power supply. None of them should be adjusted unless you know what you are doing.

Later,
Jason
M: M100, M44 for a custom amp project
Zx: Zx500, Zx450, Black Zx350
ZxTi: 4 Zx600Ti's, 1 Zx400Ti
Ti: 5 800.1's & 900.7 for a custom amp project. 1 1200.1, 1 1000.2
Tantrum: 2 1200.1's, 1 600.4, 1 500.2
XS: XS6600
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knightrider358
Posts: 1318
Joined: Mon May 04, 2009 3:37 am
Location: Virginia, Near D.C.

Post by knightrider358 »

thanx jason
Current 1 of 2 current installs

HU-Alpine IVA-D310
DSP-PXA-H701
Comps-JL ZR 650
Sub-3 JL 10w6v1ae's sealed
Highs amp-MS275
Mids amp-MS2125
Subs amp-MS2250TA
ttocs
the Floor Sweeping Hack with Golden Ears
Posts: 14797
Joined: Fri Dec 19, 2008 9:53 pm

Post by ttocs »

I know what I am doing, my dad is a tv repairman with a rightchus set of tools, I can fix it........
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Jacampb2
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Joined: Sat Apr 19, 2008 11:57 pm
Location: Beaverton 48612

Post by Jacampb2 »

ttocs wrote:I know what I am doing, my dad is a tv repairman with a rightchus set of tools, I can fix it........
Did you take it off some sweet jumps?
M: M100, M44 for a custom amp project
Zx: Zx500, Zx450, Black Zx350
ZxTi: 4 Zx600Ti's, 1 Zx400Ti
Ti: 5 800.1's & 900.7 for a custom amp project. 1 1200.1, 1 1000.2
Tantrum: 2 1200.1's, 1 600.4, 1 500.2
XS: XS6600
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