Amp and Fuse questions

[speedyjuarez Premium Member]

Okay so I just got my two batteries put in the back of my Tahoe and I added a BRX 2000 amp. I think what I'm doing is strapping the amps. I will be running one amp to each sub (2x subs = 2x amps).

-I think I need to run one sub to the master and one sub to the slave.

-Also how close to the back batteries do I fuse? (6 inches etc)

-I also want to make sure I understand strapping these amps. From the manual it says run one rca from the master to the slave. Is it that easy? one cable so they have the same gains and signal ?

Again sorry for the newb question but this is my first multi amp setup with extra batts.

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[speedyjuarez Premium Member]

Okay so each amp has two 1/0 runs to it and I fused them 14 inches from the rear batts. Each run has a 300 amp fuse, is this to high?

I just test drove it and it was really bad, no power what's so ever. I disconnected the slave/sub and got a little more power from the one amp/sub. the batts have two runs of ground coming from the front batt, and the front batt is grounded to the frame/motor/alt. I had eliminated one ground from the frame to the amps, I guess that's my problem on no power?

 

[speedyjuarez Premium Member]

posted twice, couldn't delete

 

[speedyjuarez Premium Member]

I think I have it figured out.

I ran a ground from the rear batts to the frame. I also noticed a decrease in the sub power when I connected the slave, since I'm not bridging the subs this could've been my problem. I put both amps as masters, ran a RCA between both amps and gain matched using my CC1. Seems way better, haven't drove around yet with full volume.

 

[wew lad 5,000+ posts]

ideally you have all sources of power fused within 18 inches. alternator included, but most of us dont do that due to voltage drop. this means that you need to have the wire fused at the maximum ampacity next to every battery. make sure if you are running your rear batt to the frame, that you have a solid copper wire from your frame up front to the alternator and front batts. ideally you would run a positive and a negative but it may not be necessary for you.

if running them strapped makes it worse then i have to say you likely set it up improperly. gain matching with a DMM works well too, but I couldn't honestly tell you if it's as good as strapping the amps because the designer might take time delay and phase into account

 

[speedyjuarez Premium Member]

ideally you have all sources of power fused within 18 inches. alternator included, but most of us dont do that due to voltage drop. this means that you need to have the wire fused at the maximum ampacity next to every battery. make sure if you are running your rear batt to the frame, that you have a solid copper wire from your frame up front to the alternator and front batts. ideally you would run a positive and a negative but it may not be necessary for you.
if running them strapped makes it worse then i have to say you likely set it up improperly. gain matching with a DMM works well too, but I couldn't honestly tell you if it's as good as strapping the amps because the designer might take time delay and phase into account

Yes I have a Big 3/4 up front (thanks mylows10), I plan on adding one or two more runs from the 275 amp alt to the front batt and a few more grounds of 1/0 to everything.

I did the gain matching using the SMD CC1.

 

[wew lad 5,000+ posts]

have you tried measuring your voltage drop? best place to ground the amp is directly the body and then run a ground strap from the frame to the body. best best place for high power set ups is direct to the battery

you mentioned you think you lost power because you're not running them bridged? is your final ohm impedence at the amplifiers 2x what it is at each amp? i.e. most amplifiers strapped can take a 2 ohm load because each mono amp is 1 ohm stable. there's a weird way of doing it... id have to see the manual for your amp lol

 

[speedyjuarez Premium Member]

have you tried measuring your voltage drop? best place to ground the amp is directly the body and then run a ground strap from the frame to the body. best best place for high power set ups is direct to the battery
you mentioned you think you lost power because you're not running them bridged? is your final ohm impedence at the amplifiers 2x what it is at each amp? i.e. most amplifiers strapped can take a 2 ohm load because each mono amp is 1 ohm stable. there's a weird way of doing it... id have to see the manual for your amp lol

The subs are not bridged, they each have their own enclosure.

I just drove around and the amp I gain matched was cool but that independent sub was smelly. I'm thinking I should treat each sub/amp combo (subs in separate box) as independent setups, Then use my DD1 to set my gains for each amp????

 

[hispls 5,000+ posts]

So you attempted to strap these amps without connecting the - speaker outputs of each to the other? You're really fortunate you didn't break those amps. If you don't understand strapping amps just use Y splitter from the HU to the amps and set gains separately.

 

[speedyjuarez Premium Member]

So you attempted to strap these amps without connecting the - speaker outputs of each to the other? You're really fortunate you didn't break those amps. If you don't understand strapping amps just use Y splitter from the HU to the amps and set gains separately.

Yeah, I guess I thought strapping meant just matching gains and LPF settings.

 

[wew lad 5,000+ posts]

read the manual it will tell you how to properly strap those amplifiers..

 

[massivespl]

Strapping svcks, gain matching svcks. Sell both Hifonics amps and get a nice 3500-4k amp and be happy.

 

[hispls 5,000+ posts]

Strapping svcks, gain matching svcks. Sell both Hifonics amps and get a nice 3500-4k amp and be happy.

Strapping is great if you understand what you are doing.

 

[wew lad 5,000+ posts]

a lot of people strap amps lol it works just the way its supposed to and theres a reason why amplifier designers add that functionality