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balance/SQ, lossless line voltage?

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what's the kx3 doing exactly? 

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i still have fuses at the battery but its a single 0ga wire going back into a distro block that goes out into 4ga and 8ga. i added fuses to the 4 and 8ga lines in addition to the battery.

the KX3 is doing exactly what it did before. its crossing over the front input to a high and mid range (my alpine tweets and crachendo mids).

i really do not think the amp is a placebo, im going to test the old amps out of the truck today but i do think they are failing.

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You aren't blind a/b testing. No way, no how you are going to have a real result. Absolutely silly to even post anything regarding this. Proven fact that whichever setup that yields you more gain you will perceive as better. Nothing else. Classic trick that people have utilized in stereo demo's in stores for decades.

Of course, your old install was so jacked that it is possible you've "fixed" something, but don't credit the amp.

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i tested the voltage output using a DMM on the amp. i used my ipod with 3.5 to RCA on my bench. i consistently got about 12V less output from the right channel regardless of input volume or configuration. i can easily hear distortion in higher frequencies out of the 6.5 mid-range i hooked it to at 1/4 - 1/2 volume to the amp. i also noticed that if i tapped the case of the amp i would get an audible popping noise from the tweeter in the 6.5 as well as the right channel would cut out from time to time. the amp was truly screwed. i turned up the volume to my kicker amp yesterday and it cut out on me, i found the problem in my right speakers (that were being powered by this old amp) as they have a dead spot at rest and when you tap the cone in or out slightly they hit 1.2 ohm (4 ohm speaker) before dropping out if you press the cone in further. i believe the coil is coming unwound (these are the crescendos that are about 4 months old). its hard to say what caused what to die but in either case ill be replacing the lot.

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i tested the voltage output using a DMM on the amp. i used my ipod with 3.5 to RCA on my bench. i consistently got about 12V less output from the right channel regardless of input volume or configuration. i can easily hear distortion in higher frequencies out of the 6.5 mid-range i hooked it to at 1/4 - 1/2 volume to the amp. i also noticed that if i tapped the case of the amp i would get an audible popping noise from the tweeter in the 6.5 as well as the right channel would cut out from time to time. the amp was truly screwed. i turned up the volume to my kicker amp yesterday and it cut out on me, i found the problem in my right speakers (that were being powered by this old amp) as they have a dead spot at rest and when you tap the cone in or out slightly they hit 1.2 ohm (4 ohm speaker) before dropping out if you press the cone in further. i believe the coil is coming unwound (these are the crescendos that are about 4 months old). its hard to say what caused what to die but in either case ill be replacing the lot.

Clipped to death perhaps, heated the shit out of the coils and burned off the glue.

Efficiency is your friend, you don't need a ton of power to achieve what you're after.

I mean overall efficiency by the way, the whole front stage, not driver parameters.

Edited by SpeakerBoy

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yea thats what im lookin for. better speakers that need less power to give me the volume. shallower mounting and better response curves. i dont know what im going to replace them with yet, still looking around.

got my first lesson on fiber-glassing custom boxes the other day tho. that was very interesting. built a sealed box for a single 200W JL 10", i was surprised to see just how strong a single layer of fiberglass is

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yea thats what im lookin for. better speakers that need less power to give me the volume. shallower mounting and better response curves. i dont know what im going to replace them with yet, still looking around.

got my first lesson on fiber-glassing custom boxes the other day tho. that was very interesting. built a sealed box for a single 200W JL 10", i was surprised to see just how strong a single layer of fiberglass is

Why do you care about power, it is cheap. That also wasn't the point made above.

And a single layer of glass is NOT strong. You need way more.

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yea thats what im lookin for. better speakers that need less power to give me the volume. shallower mounting and better response curves. i dont know what im going to replace them with yet, still looking around.

got my first lesson on fiber-glassing custom boxes the other day tho. that was very interesting. built a sealed box for a single 200W JL 10", i was surprised to see just how strong a single layer of fiberglass is

screw efficiency and small mounting depth, imo. i'm not afraid to cut my doors up. 

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we used 3/4 MDF to hold the front speaker, placed plastic tape to forum a sheet that covered the area to be molded, layered a single layer of glass to get the back of the box and waited for it to set. we then removed the mold, cut the excess off the edges that were not needed, stapled the MDF to the sides of the box that extended properly and then glassed around the wood to the glassed rear mold. tin foil was used to provide support for the open areas between the mold and MDF face while the wet glass was setting. once that was done we used resin mixed with "kitty hairs" (single flakes of glass) mixed up to seal around the MDF on the inside and then patch any holes that were not covered in the single layer for the backing. then a second layer of glass was placed from the inside out on the box. once set over night we sprayed it with contact adhesive and coated it in trunk liner.

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i tested the voltage output using a DMM on the amp. i used my ipod with 3.5 to RCA on my bench. i consistently got about 12V less output from the right channel regardless of input volume or configuration. i can easily hear distortion in higher frequencies out of the 6.5 mid-range i hooked it to at 1/4 - 1/2 volume to the amp. i also noticed that if i tapped the case of the amp i would get an audible popping noise from the tweeter in the 6.5 as well as the right channel would cut out from time to time. the amp was truly screwed. i turned up the volume to my kicker amp yesterday and it cut out on me, i found the problem in my right speakers (that were being powered by this old amp) as they have a dead spot at rest and when you tap the cone in or out slightly they hit 1.2 ohm (4 ohm speaker) before dropping out if you press the cone in further. i believe the coil is coming unwound (these are the crescendos that are about 4 months old). its hard to say what caused what to die but in either case ill be replacing the lot.

 

how you managed to kill the amp will be important to understand so that it doesn't happen again. The speaker was probably killed by thermal failure. cut it up and take a look. 

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we used 3/4 MDF to hold the front speaker, placed plastic tape to forum a sheet that covered the area to be molded, layered a single layer of glass to get the back of the box and waited for it to set. we then removed the mold, cut the excess off the edges that were not needed, stapled the MDF to the sides of the box that extended properly and then glassed around the wood to the glassed rear mold. tin foil was used to provide support for the open areas between the mold and MDF face while the wet glass was setting. once that was done we used resin mixed with "kitty hairs" (single flakes of glass) mixed up to seal around the MDF on the inside and then patch any holes that were not covered in the single layer for the backing. then a second layer of glass was placed from the inside out on the box. once set over night we sprayed it with contact adhesive and coated it in trunk liner.

 

so basically the rear of the enclosure is molded into a pocket in the corner of the trunk? and the rear of the box only consists of TWO layers of glass? 

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that is correct. 1.5-2 layers (ish). i had thought it needed a few layers but i guess not. the back of the box was very ridged as it had a good deal of bends and edges in it where it fit the trunk. the bottom however i felt may have been a little weak but as it was explained to me the hulls of fiber glass boats are only 1/8" thick so a 200W sub is not going to cause significant deflection in the glass. it was a .6 cubic box.

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that is correct. 1.5-2 layers (ish). i had thought it needed a few layers but i guess not. the back of the box was very ridged as it had a good deal of bends and edges in it where it fit the trunk. the bottom however i felt may have been a little weak but as it was explained to me the hulls of fiber glass boats are only 1/8" thick so a 200W sub is not going to cause significant deflection in the glass. it was a .6 cubic box.

 

i'd say thats still way too thin. maybe you can get away with it for that sub but it seems like a poor practice. you'll often see people stand on their box to test/demonstrate how strong it is. 

 

i've personally never done big fiberglass work but i would think 1/4 inch minimum thickness would be a good target. 

Edited by lithium

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I wouldn't even feel good using 1/8" anything in a tight spot let alone as common practice. My woofer snaps screwheads off in 3/4" wood, and it's only on double that power.

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the JL did not have any where near that much power. the only part i would say might need more is the bottom as it did have a good deal of flex to it. imo anyway, i do not know much about glassing but ill be doing quite a bit of it this year im sure.

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that is correct. 1.5-2 layers (ish). i had thought it needed a few layers but i guess not. the back of the box was very ridged as it had a good deal of bends and edges in it where it fit the trunk. the bottom however i felt may have been a little weak but as it was explained to me the hulls of fiber glass boats are only 1/8" thick so a 200W sub is not going to cause significant deflection in the glass. it was a .6 cubic box.

You seriously need to stop listening to who ever you are learning from. Most kayaks are thicker than 1/8 inch and even those use some sort of foam or wood in their laminant.

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Hell I used significantly more layers than that to house my midranges in my kickpanels. Midranges.

I think you need to find a new job. Every single thing anyone there has ever told you has been wrong. And not just a little wrong.

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Perhaps my comment on local shops somewhere near page 1 now makes more sense to everyone. For once I was not being an asshole. tongue.png

That shop sounds like an utter bumblefuck of retardedness though.

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LMFAO "dumblefuck" i will need to remember that one... well it does give me access to many vehicles and products so at least thats a plus. who knows, maybe after some time here i will find my way into a more upscale establishment. regardless of the future my reasons for being on here is to keep an open mind and check everything against everything else. some where in the mess of conflicting information there is something useful.

The enclusure seemed perfectly fine on some parts but was flappy on others. when i build my first enclosure solo i will be using more layers. i am interested in what types of foam or wood is used in glass construction.

i would like to thank you all for sounding off your opinions on everything i say, this is the only place i know of to lay out what i "know" for others to tell me how incorrect i am.

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Rule of thumb is use as much wood and as little fiberglass as possible.

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