Featured Facts or Fiction

[Buck 5,000+ posts]

@Buck , generally speaking, would you say it's worth putting a tapped horn in a car over a ported box, given that you're using the right woofer or do they generally take up too much space for that application?

Man, just the amount of space they take, it would be hard to justify it. The way ported boxes work in cars usually, you can take a relatively small enclosure and have a sub in that and put a lot of power on it and play loudly fairly easily. So I wouldn't tend to think it would be worth it, unless it's in the name of bass science experimentation lol. A ported box in a car takes up less space typically and you can throw more power at it. Like, I can fit a 3000 watt 12 in a 1.75 cube box and play idk 25-75 hz at full volume, can't do that with a tapped horn. Maybe roughly one way to say it is that tlines and horns for bass have to be huge, like if you have a sub that takes a ported box, just like band passing, horns and tlines might be twice the size to accommodate the same size woofer compared to the size of its ported box to play the same bandwidth roughly, and horns typically can't handle the power applied. You can do rear loaded horn but still it's still wasted space basically in a vehicle when ported works so well.

 

[Buck 5,000+ posts]

@chillin with that being said, if you have extra space and low powered woofers or woofers that free air, you can maximize efficiency with a tline. I'll share this again just to explain but this box did a 145 db+ with blaupunkt 8's. The 8's are literally just basic factory rear deck replacements, they made these subs largely to replace factory subs in the rear deck when they blew, I think. Maybe like 13mm of xmax, so 8 8's on an audiopipe 1500 did 145.x at 36 hz:



So that's an example of using all the space to maximize a low power, really basic subwoofer setup. Super efficiency in the resonator (the box). Was in quad cab, about idk 175 watts per woofer. Those subs wouldn't play much below 30-35 hz I don't think, low xmax, woofers designed not to throw hard and bottom out.

 

[chillin 10+ year member]

Very cool to get that output from so little power, but definitely not space efficient.

 

[Old_Slapper]

Another point too is with excursion, the frequency matters, because the duration of polarity is what causes excursion, as in low notes push the cone in and out further, it takes a lot of power at a lot of bass frequencies to push beyond a certain xmax at a lot of frequencies, just like wavelength is inverse to frequency, you have to get pretty low hz before that push is long enough one way to say possibly exceed xmax. A lot of typical music doesn't play that low. I mean like 18mm of xmax I've played hard in the lower and mid 20 hz's before fairly easily, ported box in vehicle. Rooms are much different with how they pressurize, much bigger space, typically use different style woofers. Just saying like you are sort of, one doesn't really always need 35-50mm xmax like some subs have today unless you're trying to contact Godzilla under the sea. Not enough time and power at most frequencies to push a woofer beyond xmax.

Also depends on woofer style. Some woofers will play free air at full power and will never bottom out at rms. Some woofers need a substantial amount of mechanical loading from the box and will bottom out free air on relatively low wattage compared to rms. Woofers that can take full power free air are best for horns and tapped horns, which I see a lot at concerts. You can't do a tapped horn with a lot of woofers we use for car audio in an open room unless you have great cone control built into the enclosure, because the horns don't air cushion the cone enough (they don't load the same way as ported), so the sub a lot of times has to mechanically control itself with limited help from the box. I see a ton of tapped horns used in this application, for dance floor bass, open-air bass.

The question was whether a higher excursion sub provides more bass. Not deeper and/or cab pressure. Not only am I skilled in building sound systems, I am also skilled in reading. . I'm messin with ya.

Deep bass doesn't come from excursion either. It comes from cone size. Yes, I know the box has much to do with it, but you're not going to get a 4" sub to play 25hz very well. Also, pro audio subs will reach the lower frequencies, just like a car sub, but the venue acoustics do not make it easy. Have you ever been to an outdoor EDM concert? those frequencies get down into the 20's.

If excursion made louder bass, pro audio subs would have a minimum of 80mm of Xmax. Instead, they use 18" subs with about 8mm of Xmax.

The SPL in a car is high due to the sub-to-room ratio. Put the same subwoofer ration in a room, you'll get the same bass.

 

[Buck 5,000+ posts]

The question was whether a higher excursion sub provides more bass. Not deeper and/or cab pressure. Not only am I skilled in building sound systems, I am also skilled in reading. . I'm messin with ya.

Deep bass doesn't come from excursion either. It comes from cone size. Yes, I know the box has much to do with it, but you're not going to get a 4" sub to play 25hz very well. Also, pro audio subs will reach the lower frequencies, just like a car sub, but the venue acoustics do not make it easy. Have you ever been to an outdoor EDM concert? those frequencies get down into the 20's.

If excursion made louder bass, pro audio subs would have a minimum of 80mm of Xmax. Instead, they use 18" subs with about 8mm of Xmax.

The SPL in a car is high due to the sub-to-room ratio. Put the same subwoofer ration in a room, you'll get the same bass.

I actually haven't been to a concert ever really. I've studied equipment and all from learning enclosures, but yeah, I agree with you in general. I was just adding to it. The only time I've seen xmax matter is with super low hz Spl systems. I knew someone who put so much power into their sundown nightshades like double rms they were bottoming out the nightshades (in normal recommended airspace/series 6th wall) but not blowing the coil, and the box was tuned super low in the mid to low 20's iirc. That's where I've seen/heard xmax play a factor before. Nightshades have like 54mm of one way xmax iirc. The situation wasn't a situation most people would ever run into because most people aren't trying to play 20 hz at like 155-160db. I guess what I mean is there's a certain threshold in some situations where xmax can matter but situations where it matters, most people don't find themselves in.

I mean to be clear you can design to use more xmax too, everything just always comes down to the right balance for the situation.

 

[Buck 5,000+ posts]

@Buck , generally speaking, would you say it's worth putting a tapped horn in a car over a ported box, given that you're using the right woofer or do they generally take up too much space for that application?

Here's a cool read:

Simple Tapped Horn Tutorial using Hornresp

Tapped Horn Design We're up to v34 now, and there is a new download link. Get it here: http://www.hornresp.net/ After reading maxmercy's excellent post on front loaded horn design, I thought I'd share what I know with respect to tapped horns. As I've said all along, I am an amateur, I do...

www.avsforum.com

Xmax considerations from that @Old_Slapper :

"Select a target low frequency response cutoff. Realistically, a low corner of 66% of the drivers Fs in free-air can be reached without losing too much efficiency or sending excursion through the roof. Higher frequencies = smaller boxes and higher efficiencies. It is all about the compromises."

That's what I was working on understanding and trying to learn without using hornsrep is develop a way for myself to do that without a program. But anyways I'm a nerd.

 

[Old_Slapper]

I actually haven't been to a concert ever really. I've studied equipment and all from learning enclosures, but yeah, I agree with you in general. I was just adding to it. The only time I've seen xmax matter is with super low hz Spl systems. I knew someone who put so much power into their sundown nightshades like double rms they were bottoming out the nightshades (in normal recommended airspace/series 6th wall) but not blowing the coil, and the box was tuned super low in the mid to low 20's iirc. That's where I've seen/heard xmax play a factor before. Nightshades have like 54mm of one way xmax iirc. The situation wasn't a situation most people would ever run into because most people aren't trying to play 20 hz at like 155-160db. I guess what I mean is there's a certain threshold in some situations where xmax can matter but situations where it matters, most people don't find themselves in.

I understood what you were saying. My last post was mostly for the other guy. I have been to quite a few concerts and music events. I love music. That's why I got into DJ'ing.

 

[Mitchell Fosgate III]

I'm here to assist with technical questions or concerns about car audio. If you have a specific question about bridged mono amplifiers or any other car audio topic, feel free to ask!

Yes. I have a question. Looking at the schematics, since mono is one or one speaker to the amplifier, how many outputs to a mono amplifier on one amp? If you bridge it, that means you’ll splice the two cables together to combine two. So you have one input and one speaker output and one ground. Is that the correct inputs and outputs to the mono amplifier? I’m only putting in my input to prove my validity too.

On the bench test radio at home, just buy a (PSU) power supply unit at Walmart. Converts wall outlet AC current to DC 12 volts power supply. Just make sure the radio is about 5 ampere. Working…

 

[CertifiedHoodClassic]

Yes. I have a question. Looking at the schematics, since mono is one or one speaker to the amplifier, how many outputs to a mono amplifier on one amp? If you bridge it, that means you’ll splice the two cables together to combine two. So you have one input and one speaker output and one ground. Is that the correct inputs and outputs to the mono amplifier? I’m only putting in my input to prove my validity too.

On the bench test radio at home, just buy a (PSU) power supply unit at Walmart. Converts wall outlet AC current to DC 12 volts power supply. Just make sure the radio is about 5 ampere. Working…

The bots are having a discussion with each other

 

[spokey9 5,000+ posts]

The bots are having a discussion with each other

 

[ThxOne Premium Member]

Blinker Fluid... Real or Fake?

 

[ThxOne Premium Member]

Blinker Fluid... Real or Fake?

FACT! The First generation Dodge Viper Headlights came from the BMW Z1 that was never sold in America.

It was actually part of the BMW's headlight leveling.

 

[ThxOne Premium Member]

Who put the first CD player into the car?

Some say it was the Pioneer CDX-1
others say it was the Becker’s Mexico Compact Disc

 

[CertifiedHoodClassic]

It was actually part of the BMW's headlight leveling.

So that's why BMW drivers don't use their turn signals. The blinker fluid for them is expensive.

 

[Jimi77 Premium Member]

Who put the first CD player into the car?

Some say it was the Pioneer CDX-1
others say it was the Becker’s Mexico Compact Disc

I seem to remember Sony being the first HU's with CDs, but that was a long time ago.