JL 10W7 sound quality?

[Duona]

Hello,
i got used W7, visually mint condition, like a brand new, but sound-wise left me confused. Sounds boomy, vague, and not that alive. I have great wires, ported manufacture measurements box, amp with some extra power, good ground, charged battery. What am i missing? If he wasn't used for long a time maybe needs time to play in? Or maybe he was used more than it looks, can i somehow check his condition? What could be wrong?

Using JL 10W7 with Steg k1 2500

Many years ago i had one of the cheapest Jl subs and it sounded better, tho it had three times less power and was four times cheaper.

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[1aespinoza 10+ year member]

Steg k1

This is your problem right here. I have that same sub and played it on a JL HD750/1 and Class A/B amps, and it sounds awesome. I have an USAmps Merlin MD2D that has great power but shitty sound quality. It sounds exactly as you described your Steg.

 

[Jimi77 5,000+ posts]

Hello,
i got used W7, visually mint condition, like a brand new, but sound-wise left me confused. Sounds boomy, vague, and not that alive. I have great wires, ported manufacture measurements box, amp with some extra power, good ground, charged battery. What am i missing? If he wasn't used for long a time maybe needs time to play in? Or maybe he was used more than it looks, can i somehow check his condition? What could be wrong?

Using JL 10W7 with Steg k1 2500

Many years ago i had one of the cheapest Jl subs and it sounded better, tho it had three times less power and was four times cheaper.

w7s tend to sound boomy and muddy ported. It's a high Q, low FS sub, so it's going to sound boomy in the recommended ported enclosure. Given typical cabin gain, the enclosure alone puts you +6-9db at ~40hz. If added any bass boost, then that only makes the problem worse, so make sure bass boost is off. If you've ever heard 12w7 in the JL HO ported enclosure - that thing sounds boomy and muddy as hell.

If you have an EQ, try tuning 40hz down ~6db.

You can try something more like 2cuft ported and tuned to ~25hz to take some of the boom out of it or maybe ~1 cuft sealed, but either of those enclosures will cost you output, considerable output in the case of the sealed enclosure. The ported enclosure will be tricky and big due to the low tuning frequency, so you might have to consider a passive radiator design. Go sealed and you'll be wondering why your w7 is barely louder than the cheap JL on 1/4 power, but the sub will sound much much better.

 

[hispls 5,000+ posts]

What am i missing

Post up pictures of the box as it sits in the vehicle right now. What are you using for a head unit? Have you confirmed you have no EQ, bass boost, or other issues coming from the source?

W7 is a plenty capable woofer and I would suggest that box design/location would be what is going wrong. I do not believe your amp is the problem.

 

[audiobaun 5,000+ posts]

Its also type of vehicle and how the enclosure is set up in the vehicle as well.

 

[audiobaun 5,000+ posts]

What vehicle and where is the sub located? Pic of the enclosure will help also, and dimensions of the enclosure and what it is tuned too

 

[audiobaun 5,000+ posts]

You can pull the sub and check the coils with a DMM to see if its within limitations as well to verify the coils are reading correctly. Push down easily on the sub to feel and or hear and scratching as well. The sub should move freely in and out with movement by hand with a little pressure. Something that can be checked. You could also very well be over driving the sub to its mechanical limitations and clipping/severe distortion with that amp not tuned and dialed in properly?

 

[Duona]

The head unit is PIONEER DEH P4950MP, an old unit but never had an issue with it. The vehicle is very similar to Audi a4 sedan. Tried setting amplifier gain with a multimeter, I set at 47v, but now on full volume, practically nothing happens. Checked the resistance of the speaker, it showed almost 3ohm, so 3*750 is 2250 and the square root is 47.4v That's the right gain? I set that by playing 60hz test tone. I tried equalizer with flat, natural, powerful, and all the possible settings, it just got more or less boomy. Sub moves great by hand. Posting some pictures.

 

[hispls 5,000+ posts]

I set at 47v, but now on full volume, practically nothing happens.

So the sub is barely moving, or it is moving fine but it sounds weak up at your listening position? If the sub is moving I'm going to go back to my theory that it's the position of this box in the trunk. I bet if you put that in a small hatchback or SUV or even on your home theater it would sound pretty nice.

Experiment with position and aiming of that box but have reasonable expectations trying to get good low frequency out of a trunk.

 

[1aespinoza 10+ year member]

That's the right gain? I set that by playing 60hz test tone. I tried equalizer with flat, natural, powerful, and all the possible settings, it just got more or less boomy.

47v is right. Do the gain setting with the bass in the radio eq all the way up, but no bass boost. Set the amp's Slope to 24dB, Frequency to 80Hz, Bass Knob @75%, Subsonic to ~27Hz.
I assume box is s built specifically for the 10w7; otherwise you will not make it sound right regardless of any settings you try.
Also like hispls said, it is not easy to get clear bass out of the trunk.

 

[Jimi77 5,000+ posts]

47v is right. Do the gain setting with the bass in the radio eq all the way up, but no bass boost. Set the amp's Slope to 24dB, Frequency to 80Hz, Bass Knob @75%, Subsonic to ~27Hz.
I assume box is s built specifically for the 10w7; otherwise you will not make it sound right regardless of any settings you try.
Also like hispls said, it is not easy to get clear bass out of the trunk.

Why are we setting gains with maxed eq and near maxed out bass boost? That's the opposite of what most people suggest and there is no reason to believe such settings will make the sub sound any better.

 

[Duona]

Turns out i was reading the multimeter wrong, i bought a new one with auto range detection and didn't notice that it stayed in mV instead of V, tried again with an adjusted range, didn't go over 3V.
So i have gain at zero, hz at the lowest position, head unit completely flat, raise volume to 75% ant play 60hz tune, slowly start raising gain and completely turned shows around 3V. To the amp comes 12.4 DCV through speakers ports comes out 3ACV

 

[1aespinoza 10+ year member]

Why are we setting gains with maxed eq and near maxed out bass boost? That's the opposite of what most people suggest and there is no reason to believe such settings will make the sub sound any better.

That flat eq is for full range amp/speakers. Maxing out Bass eq does not adversely affect full range speakers since they are crossed @ 80Hz and above. Maxing out protects your subs from accidentally playing bass heavy songs to clipping, same thing for maxed out bass knob. As for bass boost, I do not recommend it for setting gains. So doing this is not to make subs sound better, but to giving them exactly what they need.

 

[SlugButter]

Turns out i was reading the multimeter wrong, i bought a new one with auto range detection and didn't notice that it stayed in mV instead of V, tried again with an adjusted range, didn't go over 3V.
So i have gain at zero, hz at the lowest position, head unit completely flat, raise volume to 75% ant play 60hz tune, slowly start raising gain and completely turned shows around 3V. To the amp comes 12.4 DCV through speakers ports comes out 3ACV

You have the crossover turned all the way down? It looks like it has a LPF at 40 HZ when turned all the way down. A 60 HZ test tone will be filtered out. Turn the filter up a little maybe. Is that push button on the left labeled “HP” and “PB” a switch between a high pass filter and a low pas filter?

 

[Jimi77 5,000+ posts]

That flat eq is for full range amp/speakers. Maxing out Bass eq does not adversely affect full range speakers since they are crossed @ 80Hz and above. Maxing out protects your subs from accidentally playing bass heavy songs to clipping, same thing for maxed out bass knob. As for bass boost, I do not recommend it for setting gains. So doing this is not to make subs sound better, but to giving them exactly what they need.

I'm not sure how you use an EQ. Generally they are used to create a flat response and/or reduce hot spots in a given environment. Maxing out boost/EQ options means you'll always have to leave the controls maxed out to get full output from the sub. It also means the sub will be ridiculously boosted at ~45hz (probably by 12db) from the amp plus what ever whatever frequencies his HU boosts. If that HU has another EQ control at ~45hz, he's going to be boosted ~24db at ~45hz. Makes for an obnoxiously loud set up, but not a very good sounding one.