Kac-8152d i recently got the amp to turn on. i replaced the in line fuse and the turn on lead wire, but now i can't get any sound out of my woofers. i have turned up the gain and teh woofers move but only a little. please help!!

Hello whit_hughes,

Just received your request for some information regarding Bose 501's......... Series III. Your looking for te manufacturers part # for the fuse which is in line with the woofer? The fuses used ON the Series III Crossovers (hard wired/soldered directly to crossover board/componants) have been Identified as BUSS #2494, 2amp, Quick-Blow Glass Tube Type Fuses. The fuse which is in-series with the woofer & the fuse which is in-series with the pair of tweeters are the same! In theory this means that the woofer is capable of twice the wattage of the tweeters due to the tweeters being wired in series with each other..... which in turn divides the power beween the two equaly. On the woofer circuit there is only the one speaker or voice coil obsorbing the power. The woofer circuit being wired in parallel with the tweeter circuit again splits the power between the two cuircuits..... so in an ideal situation the woofer sees 50% total input power while the tweeters each see 25% total input power;;;; totaling 100% total. The way Bose has fused them in the Series III's is such that each branch can obsorb a total of 2 amps before shutting down each indivigual branch. This can be adventageous..... should peak power be exceeded causing loss of full load abruptly, Amplifier Power Output Transistors usually blow..... however when only half of the full cuircuit shuts down due to peak power exeeding limits causing one fuse to open (blow) ... the actual impedance (resistance) of the speaker increases protecting the Amplifiers Output Transistors! Thats the reason for the 2 fuses. Each of them are identical. They are soldered into place.... via the wire which is attached to each end of the fuse. (Note; the fuse "kit" Bose is trying to sell you is an external in line fuse holder for each speaker {costing 1.29 each} & 2 fuses for each holder, One for now & One for Later aftr it blows {costing 1.00 each}..... costing Bose 6.58, neting Bose $13.42 Profit!!!! Keep in mind that this fuse WILL NOT FIX YOUR PROBLEM EITHER! DUE TO THE FUSE WHICH IS PRESENTLY BLOWN HAS NOT BEEN REPLACED!!!!! ) The one that has to be replaced is on the crossover... not between the Amplifier & the Speaker Enclosure. Tools required = 1 Long Big Straight Blade Screwdriver to pry off speaker grill, 1 Phyllips Screwdriver to remove screws seccuring woofer to encloser... be carefull not to damage/tear gasket, 1 pair side cutters to cut blown fuse out of crossover curcuit, 1 pair needle nose pliers to attach NEW fuse to crossover curcuit, 1 soldering Iron & a small piece of solder to re-solder fuses leads securly to crossover curcuit. ( replace gasket, woofer, screws, & speaker grill. ENJOY! Should additionaL informaton be required please let me know.... you'll have to leave me your e-mail address for pictures or drawings.... as I don't think they can be sent through this site. Hope this helps ya..... Its an EASY JOB...... you CAN DO IT! & will be glad you did when your done, they'll sound GREAT! ) GOOD LUCK!

Did you find a solution? Dunno if it's much help, but I just today picked up some 501s - Series I I think - ugly heavy brown material grilles - but with a manual! No fuses in these, but booklet recommends installing your own in-line fuse holders (!?). Specifies a BUSS AGC-3 fuse for amps under 50wpc; or a MDL-2 fuse for amps over 50 wpc. Can be placed is series with either or the two signal wires. Very strange.... Robin

Wire the power connection from the amp to the fuse box that is only live when the ignition switch is switch on and or the accessory is on.
When the ignition switch is off then there won't be any power to the amp. Connect this power lead with its own in-line fuse and on the power side of the fuse box before the fuses.

are you running separate amps for the woofer and speakers??? sounds like you have the woofer amp being turned on be the amp remote wire (blue/white) and the speaker amp turned on with the power antenna remote wire (blue). if this is the case you need to use the blue/white to turn both amps on.

That blue wire needs to be connected to both the receiver and the amp. It is what tells the amp to turn on when you turn the receiver on.

Your amp could be in protection mode! Sometimes turning up to high or wires touching will put in protection mode! It will have to be unplugged for a day or two to drain all power out of the memory. Leave accessorie/ignition wire hooked up, just not power and ground wiring. It should reset itself.

first of all is the amp a four way amp? if so then you need to know what the watts of the subs are (you dont want to melt them) wire + and - of channels 1 and 2 to one sub and + and - of channel 3 and 4 to second sub, nice thick lead from battery positive (fused) to positive terminal on amp thick lead from a good earth point to negative terminal on amp run a set of rca leads down the opposte side to the positive wire to prevent interference, run thin wire from remote wire of radio to the remote terminal of amp, rca's are plugged in at stereo and at the am. may need a RCA splitter to be able to power all four channels

Good luck Davelee

First check the speaker wire from the amp to the sub, see if it's connected right. Second check the rca cables that goes from your amp to the back of the deck. I f both wires are still connected fine try to replace the rca cables. If it still doesn't work the rear out put at the back of your deck, where the rca's are connected are bad. FYI deck is bad.

The sub contains the amp for the other speakers. But it sounds like the amp has a seriously damaged section and will probably have to be serviced by Bose.

check the fuse box and make sure there is no loose connection there. also check the wire that feeds power to that amp. good luck