This is what Mark Eldrige's wrote about seting up the 2118:
"Sealed or ported. Either one will need about 0.5 cubic foot if possible. Generally, keep them between ~70 HZ and 2.5 kHz. Lower is possible, but be careful, as they are not designed to be played really low with a lot of power applied. I ran mine down to around 45 Hz, but was very careful with power, and used 48 dB/octave slopes. The 2118, in my opinion, is the best sounding midbass driver I've ever used. Incredible transient behavior, very efficient, and blends well with a horn, or conventional driver system."
The 2118 is an 8" version of the 2123, a 10".
The 2118 could play at 100 db at 70 Hz w/35 watts in a. 5 cu/ft box before reaching full excursion! How can he possibly run them this low? Cabin gain?
"Sealed or ported. Either one will need about 0.5 cubic foot if possible. Generally, keep them between ~70 HZ and 2.5 kHz. Lower is possible, but be careful, as they are not designed to be played really low with a lot of power applied. I ran mine down to around 45 Hz, but was very careful with power, and used 48 dB/octave slopes. The 2118, in my opinion, is the best sounding midbass driver I've ever used. Incredible transient behavior, very efficient, and blends well with a horn, or conventional driver system."
The 2118 is an 8" version of the 2123, a 10".
The 2118 could play at 100 db at 70 Hz w/35 watts in a. 5 cu/ft box before reaching full excursion! How can he possibly run them this low? Cabin gain?
Doug's car is pretty badassed...one of my favorites. He is running a 2 way front. Doug told me his were crossed at 90 hertz 6 dB/octave.
Steve Head is using the 2118s in his Civic in a 3 way with Scan 4s and Hiquphon tweeters. I think Steve has his crossed at 70 hertz.
The 48 dB/octave slopes will help to cross them over lower. Mark probably had a couple different system settings that were volume dependent...seeing as he had a SMPTE machine in there, I wouldn't doubt he could make changes on the fly with some of the other black boxes that he had going on.
Steve Head is using the 2118s in his Civic in a 3 way with Scan 4s and Hiquphon tweeters. I think Steve has his crossed at 70 hertz.
The 48 dB/octave slopes will help to cross them over lower. Mark probably had a couple different system settings that were volume dependent...seeing as he had a SMPTE machine in there, I wouldn't doubt he could make changes on the fly with some of the other black boxes that he had going on.
Thanks Winslow, very useful info. I think I may have confused names and setups when doing my research on ‘Car Sound & Performance’.
It seems that at those crossovers and slopes max volumes for the 218 would be at 102 db or so and max useful power would be about 60watts into 8 ohms. Does that bear out with what you have heard/know? Is 102 db so more than sufficient for dynamic bass in a moving car? What is your opinion on the best crossover for the 2123 and the DIYMA12? I know that you are very familiar with that sub.
It seems that at those crossovers and slopes max volumes for the 218 would be at 102 db or so and max useful power would be about 60watts into 8 ohms. Does that bear out with what you have heard/know? Is 102 db so more than sufficient for dynamic bass in a moving car? What is your opinion on the best crossover for the 2123 and the DIYMA12? I know that you are very familiar with that sub.
I know some of you a very familiar with the Orion GX amps. Do you think having the GX280 running the 2123 40w/ch @8 ohms, being supplied power by an 8 ga. wire is a mistake? The 280 for the sub will produce 360w and will have it's own 4 ga. Although after looking at Perry's site (BCAE) it seems that a single 4 g could supply power to everything, (360w@ 4 ohms + 80w@ 8 ohms +100@ 8 ohms +50@ 8 ohms = 590 watts.
Also is it benifical to have extra power beyond your max speaker excursion.
Also is it benifical to have extra power beyond your max speaker excursion.
mitchyz250f said:
Hi
It's when the voice coil former hits the back plate or rips from the spider causing actual physical damage to the driver.
EDIT> It's good to have headroom on your amp and speaker excursion. what is 3dB (2x power) not really going to be that much louder. Loud is good only if it sounds clean.
Hey thank again for your answers.
Sorry for being so dense, but what you are saying is that the extra power is headroom but that anything beyond xmax is non linear, not so good sounding. And that damage occurs at 19mm 'when the voice coil former hits the back plate or rips from the spider causing actual physical damage to the driver'. And I would assume that 'excursion' in this case means peak-to-peak.
TSmith - I am thinking about running a separate bridged GX280's to each JBL to get the extra headroom. That should get me about 160 watts each @ 8 ohms. How hot will they get in this application? How much ventilation will they need? I think in almost all situations I will only be using 10 watts or so.
I am still working on the box. With a job and family it doesn't leave much time for hobbies.
Sorry for being so dense, but what you are saying is that the extra power is headroom but that anything beyond xmax is non linear, not so good sounding. And that damage occurs at 19mm 'when the voice coil former hits the back plate or rips from the spider causing actual physical damage to the driver'. And I would assume that 'excursion' in this case means peak-to-peak.
TSmith - I am thinking about running a separate bridged GX280's to each JBL to get the extra headroom. That should get me about 160 watts each @ 8 ohms. How hot will they get in this application? How much ventilation will they need? I think in almost all situations I will only be using 10 watts or so.
I am still working on the box. With a job and family it doesn't leave much time for hobbies.
mitchyz250f said:
Now you're talking!
At an effective 4 ohm load, they will stay pretty warm. Hot if they're getting a workout. If there isn't enough room for convection around them, add fans. At least a couple of inches all the way around, more on top. (Obviously you were able to stay awake through heat transfer, unlike me-
)Have you decided where to put them?
And what amp will you be using on the sub in this case?
. We should form a club.
mitchyz250f said:
Behind the rear side panels? Use a fan and if reasonable, provide a way for air to come in from elsewhere. Don't make it complicated, just keep the air moving and keep it from acting like a sealed enclosure back there.
Nice "extras". If you have leftovers you don't want, I'd be interested -there's an empty Orion spot in my collection!
So that puts you at (1) 280GX/4 ohm mono + (2)280GX/8ohm mono + D200/8ohms + D100/8ohms.
Is that getting close to your alternator's ability to keep up? If so, that's where the old Orions tend to fail. Be sure you can supply their demands or the numbers 6488 and 6491 will become significant to you.
I’ll keep the three GX280’s and the D200 under the seats. I’ll move the tweeter amp to the spare tire area. No fans, this is getting too complicated.
Thanks for your input TS regarding current load. I think it is important to keep the math at the forefront here. I know the GX's are pretty bullet proof as long as you don’t short them out or can not provide the current the needed. Heavy duty power wires aren’t going to help if the alternator can’t supply the power.
Please tell me if these actions mitigate the current requirements somewhat;
-I will be going with a D60 for the tweets instead of the D100.
-I think I am going to be crossing the midbass to midranges at 400 Hz. This (I think?) should reduce the amount of power I need for them since they will not need to produce sounds below 400 Hz. Do you think I will still need the D200 or could I use the D100 for the mids?
- The midbasses playing at 5 watts should get me to 102 db for each speaker, plus 3 db for the 2nd speaker, plus s5 db cabin gain, should get me to 110 db.
I used some serious extrapolation here so if this does not make any sense let me know.
Thanks for your input TS regarding current load. I think it is important to keep the math at the forefront here. I know the GX's are pretty bullet proof as long as you don’t short them out or can not provide the current the needed. Heavy duty power wires aren’t going to help if the alternator can’t supply the power.
Please tell me if these actions mitigate the current requirements somewhat;
-I will be going with a D60 for the tweets instead of the D100.
-I think I am going to be crossing the midbass to midranges at 400 Hz. This (I think?) should reduce the amount of power I need for them since they will not need to produce sounds below 400 Hz. Do you think I will still need the D200 or could I use the D100 for the mids?
- The midbasses playing at 5 watts should get me to 102 db for each speaker, plus 3 db for the 2nd speaker, plus s5 db cabin gain, should get me to 110 db.
I used some serious extrapolation here so if this does not make any sense let me know.
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mitchyz250f said:
What sparked the comment was simply the move from 8 ohm single 280 operation to effectively 4 ohm on two, plus the third bridged into 4 ohms. It was a gut reaction, maybe unfounded. I don't remember current draw for them, but would estimate about 35A+2*20A at full power.
I don't *think* the Soundstreams will be significant contributers no matter which 2 you choose, because of both the 8 ohm load and the frequency range. The 8 ohm drivers would sway me to use the bigger amplifiers.
UNLESS they are very inefficient and/or draw heavy idle current.
Personally, I've only had a D200 and not in a situation that caused me to pay attention to such things. Anyone else have experience to share with these?
Of course if they're delivering significant amounts of current, the small speakers will act as fuses.
(Unrelated - be sure to use caps in series with the tweeters for DC and amp turn-on protection, since they will have no passive x/o)
5W could be a reasonable average power for an amp that's cranked and delivering 160W transients, depending on the music. 20log(160W/5W) = 30dB of dynamic range.
If it were me, I would proceed as planned and add a voltmeter (cheap and easy) to watch while getting to know the system.
Ts - Why are 6488 and 6491 numbers? Are they transisitors that have to be replaced when the Orions don't get enough current?
I have made draft baffles out of pink insulation form from HD. I use it inplace of MDF when just trying to get an idea of what works. It looks like .5 cu/ft will not be a proplem.
I have made draft baffles out of pink insulation form from HD. I use it inplace of MDF when just trying to get an idea of what works. It looks like .5 cu/ft will not be a proplem.
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