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The short version is that those Hellas require more power than the OEM relay supplies, apparently. I don't know why it needs so much more power especially as there's only 6db difference between them and PIAAs. That's a db value difference less than the "volume" of normal human breathing.
That’s not necessarily how the decibel scale works. Its log based not linear so every 10 dB increase is a magnitude increase (x10) in sound intensity. That means that the noise your ear perceives roughly doubles every 10 dB. Because of this, a change 50dB to 56dB is much less than a change of 112 to 118. For comparison 110 dB to 120 dB is like going from a stock car horn to front row at a rock concert.


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That’s not necessarily how the decibel scale works. Its log based not linear so every 10 dB increase is a magnitude increase (x10) in sound intensity. That means that the noise your ear perceives roughly doubles every 10 dB. Because of this, a change 50dB to 56dB is much less than a change of 112 to 118. For comparison 110 dB to 120 dB is like going from a stock car horn to front row at a rock concert.


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Yup! A typical car horn is about 110 dB whereas a typical fire engine siren is 120 dB. I know which one hurts my ears when they go by...
 
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Well, there is a sliding scale when measuring decibels however, db and perception of volume is based on the frequency. With the referenced products sitting within very small range, its very likely that the 6db difference is as little difference to the ear as breathing. Regardless, it’s plausible to assume that the marginally higher frequency Hellas @ 6db more than the PIAAs cannot possibly be in excess of normal speaking volume. I think thats an extremely generous window because apparently thats about 60bd (@ about 85-255 hz) and I think that’s a reasonable estimation.

Electronic sirens, such as fire trucks and police, are much higher in frequency. Therefore, the db level is much higher even if using the same input power and driver, which it’s not. Our referenced horns are diaphragm while the siren is not. My PIAAs use 2.7 amps per horn, that equals about 32.5 watts. Sirens are driven with 100-500 watts. A quick look just now indicates that most emergency vehicle sirens run 200-300 watts. We also have to take directional focus into account. I honestly don’t know how electronic sirens are directed but I assume it’s very effectively while we all know car horns are very poorly directed. My PIAAs direct down while the Hellas project straight out the face.

Also, how are these two products measured? Everything I’ve ever seen says car horns are tested at nearly 7 feet while sirens are at 10 feet. Although marginal, we can safely assume that standing 3 feet closer to the siren will be louder. Unfortunately, I have no source to tell me at what distance a particular rock concert db was measured, nor do I know the acoustics of the facility it was tested in. For all I know, the measurement was taken either in front of the main speaker or in the nose bleed section of a purposefully designed amphitheater.

What I do know is that the perceived volume at the 2 products cannot be large because of the narrow db rating and frequencies used. Just because I’m being pestered to stop writing and go out for dinner; I don’t know about anybody else but I bet my ears would hurt if I stood 10 feet away from either horn and someone laid on it as it if were a siren.
 

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Well, there is a sliding scale when measuring decibels however, db and perception of volume is based on the frequency. With the referenced products sitting within very small range, its very likely that the 6db difference is as little difference to the ear as breathing. Regardless, it’s plausible to assume that the marginally higher frequency Hellas @ 6db more than the PIAAs cannot possibly be in excess of normal speaking volume. I think thats an extremely generous window because apparently thats about 60bd (@ about 85-255 hz) and I think that’s a reasonable estimation.

Electronic sirens, such as fire trucks and police, are much higher in frequency. Therefore, the db level is much higher even if using the same input power and driver, which it’s not. Our referenced horns are diaphragm while the siren is not. My PIAAs use 2.7 amps per horn, that equals about 32.5 watts. Sirens are driven with 100-500 watts. A quick look just now indicates that most emergency vehicle sirens run 200-300 watts. We also have to take directional focus into account. I honestly don’t know how electronic sirens are directed but I assume it’s very effectively while we all know car horns are very poorly directed. My PIAAs direct down while the Hellas project straight out the face.

Also, how are these two products measured? Everything I’ve ever seen says car horns are tested at nearly 7 feet while sirens are at 10 feet. Although marginal, we can safely assume that standing 3 feet closer to the siren will be louder. Unfortunately, I have no source to tell me at what distance a particular rock concert db was measured, nor do I know the acoustics of the facility it was tested in. For all I know, the measurement was taken either in front of the main speaker or in the nose bleed section of a purposefully designed amphitheater.

What I do know is that the perceived volume at the 2 products cannot be large because of the narrow db rating and frequencies used. Just because I’m being pestered to stop writing and go out for dinner; I don’t know about anybody else but I bet my ears would hurt if I stood 10 feet away from either horn and someone laid on it as it if were a siren.
Early dinner! ?

I'd love to understand more about this. The only vehicle that hurts my ears more than a fire engine passing us, Code 3, while we're walking around Santa Monica, is a Harley with what must be an illegal decibel limit...

Edit: This CA vehicle code doesn't help much:

27000.
(a) A motor vehicle, when operated upon a highway, shall be equipped with a horn in good working order and capable of emitting sound audible under normal conditions from a distance of not less than 200 feet, but no horn shall emit an unreasonably loud or harsh sound. An authorized emergency vehicle may be equipped with, and use in conjunction with the siren on that vehicle, an air horn that emits sounds that do not comply with the requirements of this section.
 

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I didn't read the comments in this thread.. really don't care about anyone else's opinion on decibels or anything.

I happened to see this sale on Hella horns for $14 for as long as it lasts https://sellout.woot.com/offers/hella-loud-super-tone-electric-horn-3

I had these horns on my old car, and while they are generally regarded as one of the best horn upgrades, I did not notice any difference between them and the stock horn at the time. Had them wired directly to the battery and everything... seemed to be the same.

If you are looking for a horn project, you might as well save some cash on this sale. Then combine them with any of the harnesses/mounting options that might be available on any Subaru accessory sites....
 

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Discussion Starter #26
Yeah, that's about how I read it but I don't think the total price would be much different.



The short version is that those Hellas require more power than the OEM relay supplies, apparently. I don't know why it needs so much more power especially as there's only 6db difference between them and PIAAs. That's a db value difference less than the "volume" of normal human breathing.

I haven't seen an installation but YouTube can probably walk you through both PIAA and Hella's installation. That may also address some questions, even if not Subaru specific.

You can expect to loose your warranty on the immediate wiring harness because you cut it but, as I understand it, they'd have to prove that the changes you made are what caused a reported problem. However, that is probably country specific and I have no idea how the Republic of the Philippines, Subaru Philippines or Motor Image Pilipinas, Inc handles that.
Subimods has the whole kit for the Hella Sharptone at around $100+ but the PIAA's are just around $60+, right? Am I missing something?

Aren't there sort-of male-to-female adapters that would convert the OEM wiring harness connectors to standard connectors? Most people here don't follow any kind of standard and they splice/tap anywhere possible. I'm far from being like that which is why I'm super strict in any mods I try to do (or at least have a local installer do). Plus I took up Electronics Engineering in college so I understand as much. I just asked a local installer that I know and he said that he just taps on to the OEM wiring harness when installing horns.

I didn't read the comments in this thread.. really don't care about anyone else's opinion on decibels or anything.

I happened to see this sale on Hella horns for $14 for as long as it lasts https://sellout.woot.com/offers/hella-loud-super-tone-electric-horn-3

I had these horns on my old car, and while they are generally regarded as one of the best horn upgrades, I did not notice any difference between them and the stock horn at the time. Had them wired directly to the battery and everything... seemed to be the same.

If you are looking for a horn project, you might as well save some cash on this sale. Then combine them with any of the harnesses/mounting options that might be available on any Subaru accessory sites....
That's definitely a good price but I was hoping they were for the Sharptones. Based on the videos I'm watching, I don't like the sound of the Supertones.
 

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Recently purchased Hella Twin Tone Trumpet Horn Kit 01122583.
It was $30 on Ebay.
Going to replace stock ones with the new Hella Twin Tone ones.
The new ones have two terminals... so one goes to ground / car metal body.
Thinking of making a custom ground wire harness from a grounding bolt (close to air filter box) all the way to both horns.
Going to zip tie in a few points to the stock horn harness.

Will make a few pics as I finish the project.
 

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I'd like to know more about the science of it for sure. Yeah, one thing a forum like this is good for is side debates about a topic. We have to be careful to not overpower the intent of the thread, as a number of us have done form time to time :rolleyes:.

I haven't seen any adapters to convert Subaru OEM horn connectors to standard connectors. I'd be surprised if they exist. It took me maybe 5 minutes to cut the OEM harnesses, solder standard clips and heat shrink them. You could use a tap instead, I just didn't want the loose connector.

If you hit the Hella and PIAA (and others) website, you can hear each of their products.
 

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I'd like to know more about the science of it for sure. Yeah, one thing a forum like this is good for is side debates about a topic. We have to be careful to not overpower the intent of the thread, as a number of us have done form time to time :rolleyes:.

I haven't seen any adapters to convert Subaru OEM horn connectors to standard connectors. I'd be surprised if they exist. It took me maybe 5 minutes to cut the OEM harnesses, solder standard clips and heat shrink them. You could use a tap instead, I just didn't want the loose connector.

If you hit the Hella and PIAA (and others) website, you can hear each of their products.
Moi?

I just went to the sites as it's been on my list for a while. Maybe a Christmas present for OAK. I like the PIAA bass horns...
 
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I'd like to know more about the science of it for sure. Yeah, one thing a forum like this is good for is side debates about a topic. We have to be careful to not overpower the intent of the thread, as a number of us have done form time to time :rolleyes:.

I haven't seen any adapters to convert Subaru OEM horn connectors to standard connectors. I'd be surprised if they exist. It took me maybe 5 minutes to cut the OEM harnesses, solder standard clips and heat shrink them. You could use a tap instead, I just didn't want the loose connector.

If you hit the Hella and PIAA (and others) website, you can hear each of their products.
Yeah, I like the sound of both the PIAA and the Sharptone. What made you say that they don't differ much in price though? You won't lose any OEM part of the harness when you use taps, right? I've never tried using taps except for add-a-fuse taps when I installed my Viofo dashcam, so there's that.
 

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Yeah, I like the sound of both the PIAA and the Sharptone. What made you say that they don't differ much in price though? You won't lose any OEM part of the harness when you use taps, right? I've never tried using taps except for add-a-fuse taps when I installed my Viofo dashcam, so there's that.
I can get the Hellas for $48 CAD and the PIAAs for $64 from Amazon; less than $20 difference isn't significant.

I quickly Amazoned behind the grill mounting brackets and they appear to be $20-30 CAD. That puts the Hella behind the grill installation $4-16 more than the PIAA OEM install. You could use a bracket to install the PIAAs behind the grill if you want too but I also don't know how much wire you'll have to purchase (if any) to install out of OEM location.

Correct, you will not loose the OEM connectors when using taps like theses:

298369


I just didn't want to deal with any lose ends so I cut off the connectors.
 

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Discussion Starter #32
I can get the Hellas for $48 CAD and the PIAAs for $64 from Amazon; less than $20 difference isn't significant.

Correct, you will not loose the OEM connectors when using taps like theses:

View attachment 298369

I just didn't want to deal with any lose ends so I cut off the connectors.
Ah. I was talking about the kit. Like I said above:

Subimods has the whole kit for the Hella Sharptone at around $100+ but the PIAA's are just around $60+. So the total overall cost for the Sharptones would be more.
 

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Significantly, if you order from there. Check out what Amazon can do for you but confirm that Subimods comes with all necessary wiring. I'll probably have a look later but I just got tagged for a meeting.

edit: Kinda looks like Subimods charges a premium to add some covered wire. However, it would be easy to install.
 

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I managed to get denso clamshell that sounds similar like hella or fiamm with half the price, they claim their product is more waterproof but let see how long it last. The italian one so far always die within 3-5 years
 

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Discussion Starter #35
I can get the Hellas for $48 CAD and the PIAAs for $64 from Amazon; less than $20 difference isn't significant.

I quickly Amazoned behind the grill mounting brackets and they appear to be $20-30 CAD. That puts the Hella behind the grill installation $4-16 more than the PIAA OEM install. You could use a bracket to install the PIAAs behind the grill if you want too but I also don't know how much wire you'll have to purchase (if any) to install out of OEM location.

Correct, you will not loose the OEM connectors when using taps like theses:

View attachment 298369

I just didn't want to deal with any lose ends so I cut off the connectors.
I see. So I guess if I was to be more on a budget with less "modifications", I would need to go with the PIAA's. The metal bracket that you needed to bend when you installed them was the bracket on the horns themselves, right? Not any bracket in the car?

Also, what are those taps called?
 

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I see. So I guess if I was to be more on a budget with less "modifications", I would need to go with the PIAA's. The metal bracket that you needed to bend when you installed them was the bracket on the horns themselves, right? Not any bracket in the car?

Also, what are those taps called?
the taps are generally refereed to as tap-in wire splices. Here's a link for a store local to me.

The metal bracket was on the horn itself; see the blue circle below.

298373
 

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I believe if you want to swap out the original horns you have to remove the front bumper. I put Supertones on our ‘11 outback when we got that but only had to remove the grill to put them in and remove OEM horns.
 

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I believe if you want to swap out the original horns you have to remove the front bumper. I put Supertones on our ‘11 outback when we got that but only had to remove the grill to put them in and remove OEM horns.
it is probably easier to drop the bumper but I didn’t have to.
 

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it is probably easier to drop the bumper but I didn’t have to.
I had Fiamm air horns on my Impreza but left them on the car when I sold it. Very nice sound. Moved the pedestrians right smartly! I'm considering them again for my present vehicle.

Wouldn't it be easier to leave the OE horns in place and just cut them out of the circuit and connect the new ones into the circuit?
 

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I believe if you want to swap out the original horns you have to remove the front bumper. I put Supertones on our ‘11 outback when we got that but only had to remove the grill to put them in and remove OEM horns.
No, you dont need to open bumper, just remove the plastic shield above radiator will do. I am not sure how many people are aware that crosstrek comes with 2 horns that are installed on separate location. The other one is near the dash within the engine bay.
 
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