Rockford Fosgate 800a2, MA Audio MA121XQ 12's bass testing vid-1

[kskate91]

Great to hear that. Yeah they are powerful little amps I love those .2 series amps. Let me know how the repair turns out man

[kskate91]

Aw sorry to hear that bro it will live to play again trust me. Very easy repair job if the mehsa solder pads are still good your good. Ebay has the original Harris IRF540 fets for I think 1.50 a pop and IR brand P channel fets too. I bought those for a recent repair on a 55.2 with a blown channel and power supply. Works good as new :) I have a million of those chips if you need some I would send you some just in case you know if u get some DSM amps or more .2 / .4 amps with xcards. Make a vid o

[621ELECTRONICS]

@kskate91 Yep, MESHA is good still. Looking at the schematic it seems the Xcard can be bypassed fairly easy for full range. I pulled the bad parts from the blown channel & replaced a missing resistor in the good channel (LEFT) & had to reset the bias as someone fooled with it, but got the LEFT channel running fine & sounds great! Just need some FETs, source resistors & an SMD transistor or two for the bad channel & it will live again! The one channel drove my 15” MTX house speakers ok! Later!

[kskate91]

Ahh bummer, yepperzz mine came today in the morning. And best part it is fully functional! Looks like a small signal trace was repaired bc theres a thin blck wire soldered underneath the board but no prob it works fine. I'm pretty sure yours is probably gonna be another good score that works :) those 55.2's are seriously no joke man! I ran one 2 ohm mono with a CVR 10 it was the best setup at that time.

[621ELECTRONICS]

@kskate91 It works? SWEEEEET! I did not expect that man, I know they said they were untested or something, but that usually means there blown, lol, but not always, sometimes they are truly untested. I can’t wait to get mine for sure, lol. The mail man just came by a few minutes ago & no amp :-(. Our mail people screw around, its probably on the truck & he did not feel like coming to the door, it happens a lot here, haha. I’ll try to post a vid at some point after I get it!

[kskate91]

Yo did your P55.2 come to ya yet?

[621ELECTRONICS]

@kskate91 Nope, still not here yet :-( The tracking shows it was accepted at there local postal facility on 22nd & left there later that day. So I will assume it was shipped the 22nd & won’t be here for a few days yet, was hoping to get it sooner then that, but oh well, no biggie. Did you get yours yet?

[621ELECTRONICS]

@kskate91 Well the 55.2 came today, but its in bad shape :-( Its missing the Xcard which I forgot they used them in the earlier amps. The output FETs for one channel have been replaced & are not even soldered down & are bad, haha, one of the source resistors has been replaced with the wrong one & its missing most of the terminal screws & some MESHA screws & the remote turn on tab is missing. I hope I can rig up something for an Xcard, if not, I am not sure its worth repairing without the card.

[imupabove]

hey .. i just picked up this amp (800a2) locally... are you running to two power wires into the amp? b/c right now im only running one power and ground wire.. what do you think? should i run 2 wires for both power and ground? it sounds fine right now but i think its only showing half its power? thanks.

[621ELECTRONICS]

@imupabove What size power wire are you running from the battery back? You need a minimum of 4 gauge for this amp. I used 4 gauge from the battery into some distribution blocks then into the amps through the 2 runs of 8 gauge. The extra two 8 gauge inputs are for a capacitor (just checked my manual), but can be used for max current into the amp like I did here. As long as you got big enough wire from the battery, you could get away with 1 short run of 8 gauge into the amp.

[621ELECTRONICS]

@imupabove These amps are somewhat difficult since they use 8 gauge inputs & can’t accept bigger wire. You really need to use some distribution blocks to hook them up properly to the electrical system, both the power & ground need it. But, you do not need to use both inputs on the amp for max power, just a good idea though for less resistance & max current capability. I had the extra wire & the distribution blocks with extra outputs & figured I would use it to my advantage.

[621ELECTRONICS]

@RWL2011 It don’t sound too bad, not as loud as I would like, but not bad for the first real bass test. The box is tuned to the low 30’s so it gets pretty low! Not an SPL box by any means. I want to build a box with a changeable port. I got a scope so I can set gains no prob, but I don’t like playing with the stuff in the driveway too much, don’t want it to come up missing! The testing I do is very quick. Once I can get it into the garage and permanently installed, I will fine tune everything.

[kskate91]

@ nextrider haha nooooooo, it's the 1997 Punch 200.2.

[kskate91]

Damn that's a big box! Looks sick! Sounds like it bumps clean! My 200.2 should be here by Monday afternoon for me :) I'm really hoping it's not broken and it works, cuz I got plans for it to put to use, I'm going to try and get a couple 12's and build a nice ported box. Nice install not hating on HU man! Free fits the bill good :)

[nextrider123]

@kskate91 a rockford fosgate punch p200-2?

[621ELECTRONICS]

@kskate91 Monday ain’t too far away, lol, but I do hope the 200.2 works, that thing should do a nice job for ya. Yeah, the box is pretty big, but still not quite big enough actually, I screwed up cutting the wood several years ago & it had to be slightly smaller then planned, but its close. I think a ported box is a must for high output; you just got to tune it to where you want to achieve what you want. This ones tuned low, so not really an SPL box. I want some 18’s since the trunk is so big!

[1FCKiT3]

@621ELECTRONICS - EY WHAT SIZE GROUND WIRE ARE/WERE U USING FOR THIS SYSTEM? I GOT THA SAME AMP PUSHIN 2 12" KENWOOD KFC W3012's, I HAD A PIECE A SHIT SUPER THIN GROUND CABLE HOOKED UP THAT MELTED IN HALF AFTER A FEW MONTHS USE (THEY TOLD ME THIS WAS GONNA HAPPEN). IM JUST WONDERING WHAT GAUGE U GOT HOOKED UP AND HOW BIG I COULD GO WITH THIS AMP IF U KNOW. GET BACK AT ME.THANKS

[621ELECTRONICS]

@1FCKiT3 Its 4 gauge power & ground wires. 4 gauge is sufficient for one of these amps, but larger would be a good idea especially if you run more then one amp. I had the 4 gauge ran into distribution blocks then two 8 gauge wires from the blocks to the dual power inputs on the amp, so two 8 gauge grounds into the amp & two 8 gauge power wires about 1 to 1.5 ft long. Yeah, definitely get at minimum, good 4 gauge oxygen free copper wire. Your power & ground wires should be the same size as well.

[1FCKiT3]

@621ELECTRONICS i heard tha power can be smaller as long as tha ground is as big or bigger? do u know if thats true? but yeah i wouldnt mind going 2 gauge i just dont wanna buy it (especially if i buy online for cheaper prices) and have tha shit not fit know what i mean

[621ELECTRONICS]

And yes, the there is a lot of stuff rattling which will be taken care of in due time. This is one of the first tests I've done with a system in this car, so I am seeing what all needs done. It will take time though.