How do I set up the low/high pass, level, and other things on my amp?

[imbored408 10+ year member]

I have mm6501 component in the front and mm651 coaxial in the rear. no sub yet.

I have the components on channel 1,2 and the coaxial on 3,4.

pic of amp control panel

I am pretty sure I turn the base boost and bass frequency to the lowest since I am not using a sub on this amp.

I have no idea what Level is and what should I set everything as?

Click to read more...

 

[disturbed471985 5,000+ posts]

MBQ 150.4???? I almost bought that amp but at the last moment I went with a different amp. U should like it had the 125.4 and it was pretty good. To much plastic for me and felt alil light compared to other amps in it power range but It did its job so you should be happy with this amp. Give me a few to look up those speakers.

 

[keep_hope_alive Premium Member]

since you have no sub, this is easy. set crossovers to full.

Level is input sensitivity. you tell the amp how strong of a signal you are giving it. set to the voltage that corresponds to the pre-out voltage of your head unit.

 

[imbored408 10+ year member]

I had them on HP FULL but I will change the Level to 4v.

What should I change the High/low pass too? Or do are they not read since I put the crossovers on HP FULL?

 

[imbored408 10+ year member]

Today my amp was getting really hot and my music would just shut off and then turn on 10 mins later. This repeated several times. Why is it doing this?

The impedence on my speakers are 2.7ohm. Did I not wire it correctly or something??

I have each speaker in their own channel. So in channel 1, one speaker has it's pos and neg in the slot. channel 2,3,4, same thing but with a different speaker.

What's going on?

 

[tommyk90 5,000+ posts]

Whats your electrical system consist of?

Where are you grounds located?

 

[imbored408 10+ year member]

I have stock cable on my battery. 0 gauge with 150 amp fuse going to distribution block in trunk with 80 amps fuses then 4 gauge into amp. 4gauge ground coming out of amp to a bolt near spare tire. Not touching paint, bare metal.

 

[keep_hope_alive Premium Member]

how long have you had the system connected and working?

use a DMM to measure between the speaker wires and from each wire to ground (disconnect from amp first). you are looking for a short circuit.

 

[imbored408 10+ year member]

I had the system for 1 hour but it cut my music off since I got it.... The amp has its green light on and two green lights at top. When the music cuts off only the bottom green light is on. When the music cuts out the amp remains on (bottom green light and MBQUART is illuminated still). The red light never turns on which would indicate it going into protect mode.

I went to my car felt the amp it was midly warm. Turned on the radio and within 1 min it started to get really ****in hot.

12.36volts from my amp ground to its power wire. High 13's with car on.

For Ohms between each speaker terminal on the amp to my negative ground I got these readings. Channel 1+. 2-, 3+, and 4- were all about 2.7Ohms while all the other speakers wires were really close to 0.

Channel 1 and 2 read about 3.5Ohms when I read them as a pair(both speaker wires on the pos stick) on the multimeter while Channel 3 and 4 had about 4.5Ohms.

When the amp was playing music I read for Channel 1+ -30ohm, Ch1-,2+,2-,3+,3-,4+, to be about 26ohms, and Ch4- to be about 50ohms. I had the negative on the amp ground terminal and the pos on each channel terminal.

The resistance of my ground location reads .2ohms

I checked my speakers and crossovers and they have tight and secure connections on them.

Also the car was parked in my garage the whole time so it isn't like the wires or amp are getting pushed around everywhere. When the music turns off it comes back on if 5 mins then turns off 5 mins. It just keeps on repeatedly doing that.

What do I do to fix it?

 

[keep_hope_alive Premium Member]

thanks for taking the measurements. sorry for the delay, i was out of town in a rural area without internet access. yes, it was nice. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

the measurements of resistance make sense. the amplifier is bridged, so only the 1+, 2-, 3+, and 4- have signal (typical for a bridgeable amp). the others are just referencing ground inside the amp. which that tells me you took that measurement with the speakers connected to the amp.

resistance between a speaker wire and ground should be near infinite (with wires disconnected from the amp) when you put the red DMM lead on one speaker wire and the black DMM lead on chassis ground. this should be the case for all 8 wires (+ & -). this test is looking for a short circuit - i.e. any wire strands that are touching the speaker basket or any wire that was pinched and shorting at metal. most wiring issues i see are at the speakers from stripping too much wire back or not using proper terminations.

it doesn't do any good to measure resistance with the amp on... and the multimeter might not like that.

it's possible the amp is bad and has an internal issue. it does sound like protection with the combination of heat, but you would expect the protect light to come on. except you say the music cuts out when the bottom power light is on. you get music when the bottom power light is off? that is interesting and a clue.

if all of your wires measure out ok then you may need to have the amp tested. MB Quart isn't the company they used to be, and are known for lower quality equipment as a result of cost savings. They are decent when they work.

 

[Lowflyin 10+ year member]

I had a directed 650 amp that did the same, my problem was grounding which you already said was good but I would recheck it to be safe if you haven't already

 

[imbored408 10+ year member]

The bottom light is always on as long as the car is on. Doesnt matter if music is playing or not. When it gets hot and the music turns off, it's still on.

Pretty sure the ground is fine. I touched many spots on the ring terminal, bolt, and the unpainted surface its on. The readings were all the same.

I sent the amp back today and not sure what amp I should get.

Front speakers are 125RMS and rear are 100RMS at 2.7ohms

Kicker zx650 (seems to be pushing it)

4 ohms: 120 watts x 4 chan.

2 ohms: 170 watts x 4 chan.

JBL GTO1004

4 ohms: 100 watts x 4 chan.

2 ohms: 150 watts x 4 chan.

Kenwood eXcelon X600F

4 ohms: 100 watts x 4 chan.

2 ohms: 150 watts x 4 chan.

Realm A600.4 (was going to get this but someone said it is flea market trash. is it really?)

4 ohms: 90 watts x 4 chan.

2 ohms: 150 watts x 4 chan.

Also some other amps seemed good but they were Class D amps, which I heard are terrible for highs.

If you know any better amps for 300 or less let me know. It has to be from a certain site that SONIC the hedgehog likes. (not sure if allowed to say site name)

 

[TheUnderFighter 10+ year member]

The JBL seems to have the right amount of power and are pretty quality. And yes, you can say Sonicelectronix all you want?

 

[imbored408 10+ year member]

just dont know if it would be considered advertising or something.

also the Kicker is a little bit too powerful right?

JBL and Kenwood one are out of stock and I dont know when or if they will restock.

 

[TheUnderFighter 10+ year member]

Hah, no worries man. We're not in the fascist regime yet.

And I didn't even notice your speakers are 2.7ohm

Yea, the Kicker is a bit too beefy, and I'd just avoid Kenwood's amps. though I don't suppose they're bad, I just don't much care for them.

I would also check Amazon, and Woofersetc, I believe they both carry JBL.