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Discussion Starter #1 (Edited)
Correct me if I'm wrong, but the only reason we see so many 8 ohm drivers, is because they were primarily designed for home, or pro concert use. How about some good, strong mid bass and mid range drivers designed with car audio in mind. No more than 4 ohm, but maybe even a 2 ohm option ?

It just takes TWICE as much amplifier, to make enough wattage playing into an 8 ohm load, and that is kind of a PITA.

Edit; I just found a Class A/B amp that is rated down to 1 ohm, and at that resistance, can make 1350 wts RMS per side ! Too bad nobody makes a 10" or 12", 1 ohm mid bass driver :( Just think how well a 12" mid bass driver with that kind of wattage could fill in between a very powerful sub woofer setup, and a couple of bad ass horns ?
 

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Correct me if I'm wrong, but the only reason we see so many 8 ohm drivers, is because they were primarily designed for home, or pro concert use. How about some good, strong mid bass and mid range drivers designed with car audio in mind. No more than 4 ohm, but maybe even a 2 ohm option ?

It just takes TWICE as much amplifier, to make enough wattage playing into an 8 ohm load, and that is kind of a PITA.

Edit; I just found a Class A/B amp that is rated down to 1 ohm, and at that resistance, can make 1350 wts RMS per side ! Too bad nobody makes a 10" or 12", 1 ohm mid bass driver :( Just think how well a 12" mid bass driver with that kind of wattage could fill in between a very powerful sub woofer setup, and a couple of bad ass horns ?
G'day mate (y)
Do you have a problem with mid bass in your current car(s); or was that just a general question? Are you thinking about the possibility of putting 10" or 12" mid bass drivers in your doors...?
 

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Correct me if I'm wrong, but the only reason we see so many 8 ohm drivers, is because they were primarily designed for home, or pro concert use. How about some good, strong mid bass and mid range drivers designed with car audio in mind. No more than 4 ohm, but maybe even a 2 ohm option ?

It just takes TWICE as much amplifier, to make enough wattage playing into an 8 ohm load, and that is kind of a PITA.

Edit; I just found a Class A/B amp that is rated down to 1 ohm, and at that resistance, can make 1350 wts RMS per side ! Too bad nobody makes a 10" or 12", 1 ohm mid bass driver :( Just think how well a 12" mid bass driver with that kind of wattage could fill in between a very powerful sub woofer setup, and a couple of bad ass horns ?
two things here.

1)most people that just want to get stupid loud, dont give two shits about SQ,
100 watts into a 4ohm driver gets WAY louder than you will listen to it and certianly louder than you can actually hear good music at.
2) higher ohms do have a good use. when you use a class A/B amplifier with something like an HLCD there is one property of that amplifier that makes sound sub-par. lets say you have an HLCD that is 112db 1w/1m. this is much louder than you will listen to it, so you will be listening at less than 1 watt in most cases.

that property is known as zero-cross distortion. on a class A/B there 1 set of transistors for the positive portion of the wave and 1 set for the negative. this issue arrises where the transistors are in the "off-state" below 0.7 volts. and that is for each polarity. so you have a space from -0.7v to +0.7v , 1.4 volts total that the transistors are off.

1 watt into a 1 ohm load would be 1 volt of signal. so you would get literally no sound. at 4 ohms it is 2 volts. so you have 0.6 volts total signal(30%) of "on-state" signal. beleive me it sounds like shit.

I ran 32 ohms on my HLCDs, meant that 1 watts required 5.6 volts of signal. 12 watts required an amplifier that was capable of about 100 watts per channel at 4 ohms. but here is the deal, 1 watt at 32 ohms, with the zero-cross losses makes for 75% signal. massive improvment.
 

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8 ohms isn't all that bad, doesn't take a lot of juice to make something with 96db get loud AF.

Power is pretty cheap these days, grab something like a tried and true jad800.4 and bridge it, that'll give you 250ish watts at 8 ohms.
 

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Discussion Starter #5
G'day mate (y)
Do you have a problem with mid bass in your current car(s); or was that just a general question? Are you thinking about the possibility of putting 10" or 12" mid bass drivers in your doors...?
Hey Captain. No, actually my little $12 Parts Express closeout mid bass drivers do surprisingly well with my current system.

But now that I'm looking into Horns for a future build, my concerns are, 1) I'd be going from 4 mid bass drivers to 2 (not that I'd have to, but one of the criteria for my next build, is going to be as few speakers as possible) and 2) I'll be trying to keep up with Horns on the top end, and an even more powerful sub woofer setup on the bottom. Only one subwoofer too, but at least 18" with 5-8 Kwts pushing it.

So yes, I'm totally thinking about 10"s or 12"s... But to be honest, I think they just need be 2 ohm either way.
 

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Discussion Starter #6
two things here.

1)most people that just want to get stupid loud, dont give two shits about SQ,
100 watts into a 4ohm driver gets WAY louder than you will listen to it and certianly louder than you can actually hear good music at.
2) higher ohms do have a good use. when you use a class A/B amplifier with something like an HLCD there is one property of that amplifier that makes sound sub-par. lets say you have an HLCD that is 112db 1w/1m. this is much louder than you will listen to it, so you will be listening at less than 1 watt in most cases.

that property is known as zero-cross distortion. on a class A/B there 1 set of transistors for the positive portion of the wave and 1 set for the negative. this issue arrises where the transistors are in the "off-state" below 0.7 volts. and that is for each polarity. so you have a space from -0.7v to +0.7v , 1.4 volts total that the transistors are off.

1 watt into a 1 ohm load would be 1 volt of signal. so you would get literally no sound. at 4 ohms it is 2 volts. so you have 0.6 volts total signal(30%) of "on-state" signal. beleive me it sounds like shit.

I ran 32 ohms on my HLCDs, meant that 1 watts required 5.6 volts of signal. 12 watts required an amplifier that was capable of about 100 watts per channel at 4 ohms. but here is the deal, 1 watt at 32 ohms, with the zero-cross losses makes for 75% signal. massive improvment.
Minbari, first off, great post ! I knew a little bit about cross losses and why higher resistance was good for home and pro audio, but your response made that much easier to understand. I think that is great info to know for the horns.

But for just regular mid bass drivers, I dunno..... I'm giving 300 wts RMS to four 8" mid bass drivers and they are not crazy loud. I mean, they keep up to my current 18" sub which is getting 2600 wts, okay..... But I don't think they could keep up to a pair of horns, and an even stronger sub woofer setup.

Oh, but as to your first point..... I guess I'm not like most people 👍 I am really wanting to create an SQL system with a great sound stage, with a beautiful EQ curve, no discernable peaks or valleys, next to zero cross cancellations (hence the super strong system with only 5 speakers total) and yet I want it to be able to hit 140 db's with music.

That's the kind of SQL system that would really me happy 🙂

PS, Most of those 140 db's would obviously come from the 18" sub with tons of wattage..... And that would actually be easy peasy, if it were tuned for SPL's. The hard part will be keeping it pretty loud, but being able to play pretty darn flat from 15-80 hz.
Fortunately, I am close to a guru who can design that.... And then I can build it 😉
 

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Do some more research mr fish. Your subs may output 140db- but full range at 140? You may as well just burst your own eardrums with a pen.
 

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Discussion Starter #8
8 ohms isn't all that bad, doesn't take a lot of juice to make something with 96db get loud AF.

Power is pretty cheap these days, grab something like a tried and true jad800.4 and bridge it, that'll give you 250ish watts at 8 ohms.
Just a lot easier / cheaper with a 2 ohm mid bass driver.....
Even a 4 ohm wouldn't be too bad if your using a bridged four channel amp.
 

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And nothing will ever play flat from 15 80 in a car, the space is too small. Why would you want to? Are you familiar with the differences in desired house curves between between cars and say a room?
 

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Discussion Starter #10
Hey guys, btw, I talked to Eric Stevens by phone this morning, after I made this OP.
Very nice, helpful guy. He does actually have 8" 2 ohm mid bass drivers for sale. Wish they were 10" or even 12"s.... But he says they do really well matched up with a pair of horns. So hen if they can keep up to a super strong sub, that would be impressive
 

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two things here.
..
2) ...
that property is known as zero-cross distortion. on a class A/B there 1 set of transistors for the positive portion of the wave and 1 set for the negative. this issue arrises where the transistors are in the "off-state" below 0.7 volts. and that is for each polarity. so you have a space from -0.7v to +0.7v , 1.4 volts total that the transistors are off.
...
That description sounds more like Class-B?

I thought Class A/B biased the plus side so it goes from say -0.1V up, and the negative side from +0.1V down?


Hey guys, btw, I talked to Eric Stevens by phone this morning, after I made this OP.
Very nice, helpful guy. He does actually have 8" 2 ohm mid bass drivers for sale. Wish they were 10" or even 12"s.... But he says they do really well matched up with a pair of horns. So hen if they can keep up to a super strong sub, that would be impressive
I would trust his advice.
 

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Discussion Starter #12
Do some more research mr fish. Your subs may output 140db- but full range at 140? You may as well just burst your own eardrums with a pen.
Yes, that's what I was saying....the sub at 140. The rest of the music loud enough to hear well, but certainly not 140 on the horns, even if that was possible 🙂
 

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Yes, that's what I was saying....the sub at 140. The rest of the music loud enough to hear well, but certainly not 140 on the horns, even if that was possible 🙂
Quantifying that SPL may be worthwhile.

For a lot of poeple it is in the 85-95 dB(A) range.
dB(A) specifically ignores the subwoofer range, and that is measured in dB(C).

If you really want 110+ dB(A), then that will be clearly in the OSHA hearing loss range, and require some significant work to achieve.
 

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Actually many Pro Audio drivers that are 8ohm are extremely efficient with sensitivity +/-90db.
Compared to most 4ohm drivers of similar size which measure in the mid 80s and are often measured at ,2.83v instead of 1/1.

What this means is you'll need alot less wattage to achieve the same loudness using an 8ohm vs 4ohm driver.
 

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Discussion Starter #16
Quantifying that SPL may be worthwhile.

For a lot of poeple it is in the 85-95 dB(A) range.
dB(A) specifically ignores the subwoofer range, and that is measured in dB(C).

If you really want 110+ dB(A), then that will be clearly in the OSHA hearing loss range, and require some significant work to achieve.
Learn something everyday :) I've seen dBA and dBC before, but had no idea what it meant. TY.
 

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Discussion Starter #17
And nothing will ever play flat from 15 80 in a car, the space is too small. Why would you want to? Are you familiar with the differences in desired house curves between between cars and say a room?
Its entirely possible, but not easy. If this stereo can do it at 160 dB'ish, and play from 18-80,
140 sounds like a piece of cake ;) Not really. But doable.... and with a LOT less equipment. We know of course the difference between 140 and 160 dB's is night and day.
BTW, I talked to the guy that built this, Brian Chamberlain a few weeks back. I'd consider having him design my sub enclosure. But we have another one of the top sub woofer gurus right here in Sacramento, Bobby Gately, who can design anything that physics allow :) I'd build it though. Building them is easy. The design is what takes skills.

Oh, and to answer your question as to "why you would want to" because hair tricks are fun :) Also, people pay good money for a massage. Why, when you can get one sitting in your car :)..... but then, I'm also one of those guys who likes music too. SQL FTW ;)
 

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Discussion Starter #18
Anyway, I'm glad I posted this, as I've learned a lot. Maybe 8 ohms is not "all bad" :) lol I was just looking at the LONG list of 8 ohm mid bass drivers available, and they have some very impressive specs. Plus, one can find 10"s and even 12"s that are fairly shallow (doable in the doors of an F150)

So now I have another question about powering these things.... class A/B or class D ? What are the differences concerning mid bass. Of course I know that most mids / highs are powered with Class A/B, and most sub woofers with Class D, but what about mid bass ? It would be cheaper, and run cooler, to use class D.... but would that hurt the SQ in any noticeable way ?
 

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Its entirely possible, but not easy. If this stereo can do it at 160 dB'ish, and play from 18-80,
140 sounds like a piece of cake ;) Not really. But doable.... and with a LOT less equipment. We know of course the difference between 140 and 160 dB's is night and day.
BTW, I talked to the guy that built this, Brian Chamberlain a few weeks back. I'd consider having him design my sub enclosure. But we have another one of the top sub woofer gurus right here in Sacramento, Bobby Gately, who can design anything that physics allow :) I'd build it though. Building them is easy. The design is what takes skills.

Oh, and to answer your question as to "why you would want to" because hair tricks are fun :) Also, people pay good money for a massage. Why, when you can get one sitting in your car :)..... but then, I'm also one of those guys who likes music too. SQL FTW ;)
I'm not sure what kind of magic Gately does but I do appreciate how he mounts his subs in the corners of this box, diagonally, rather than straight across. I assume this spaces the woofers out more to get a more efficient coupling of the two drivers.

272426
 

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Anyway, I'm glad I posted this, as I've learned a lot. Maybe 8 ohms is not "all bad" :) lol?..
...
If higher footage amplifiers are not easy to build using 12V input.
Much easier using lower voltage and higher current.

If it was not the case, then you would see less 1-ohm amplifiers,and less 1 and 2 ohm speakers.
 
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