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View Full Version : GTI series,car woofers. what Pro or home drivers are the smaller drivers based on?



FE3T
05-17-2011, 11:55 AM
I do strongly belive that the larger models are based on the current SVG models,
But what about the smaller 2 models with 3" coil and 300Wrms powerhandling?

GTI 1800 based on 2241
GTI 1500 based on 2226
GTI 1200 based on 2206
GTI 1000 based on ????
GTI 800 based on ????

I find the 800 especially interesting, are there a JBL pro or home 8" driver with similar specs?

51367
51368

1audiohack
05-17-2011, 10:18 PM
Your right about the big three as far as basket and motor assemblies are concerned. The 1800 is more like a 2240 cone and coil wise and in my opinion out performs the 2241's for sub duties.

I have never had nor seen the little ones and know nothing about them, the one you show the back of is all motor! Should you find out more please post.

Best of luck,
Barry.

FE3T
05-18-2011, 08:18 AM
GTI 1800
Mechanical parameters
Fs = 30hz
Qms = 6,77
Vas = 362,46 Liters
Cms = 0,158 mm/N
Mms = 178,141 grams
Rms = 4,96 kg/sec
Xmax = 7,62 mm
Sd = 1271 sq.cm
Dia = 40,2 cm

Electrical parameters
Qes = 0,456
Re = 2,5 ohms
Le = 1 mh
Z = 4 ohms
BL = 13,6 N/A
Pe = 600 Watts

Kombination parameters
Qts = 0,43
n* = 2,07%
Sens = 96,3 (1 Watt)

GTI 1500
Mechanical parameters
Fs = 35hz
Qms = 5,83
Vas = 188,87 Liters
Cms = 0,173 mm/N
Mms = 119,7021 grams
Rms = 4,515 kg/sec
Xmax = 7,62 mm
Sd = 877,4 sq.cm
Dia = 33,5 cm

Electrical parameters
Qes = 0,36
Re = 2,5 ohms
Le = 1 mh
Z = 4 ohms
BL = 13,6 N/A
Pe = 600 Watts

Kombination parameters
Qts = 0,34
n* = 2,19%
Sens = 95,4 (1 Watt)


GTI 1200
Mechanical parameters
Fs = 37hz
Qms = 5,83
Vas = 56,63 Liters
Cms = 0,133 mm/N
Mms = 139,368 grams
Rms = 5,557 kg/sec
Xmax = 7,62 mm
Sd = 548,1 sq.cm
Dia = 26,4 cm

Electrical parameters
Qes = 0,510
Re = 2,5 ohms
Le = 1 mh
Z = 4 ohms
BL = 13,1 N/A
Pe = 600 Watts

Kombination parameters
Qts = 0,47
n* = 0,54%
Sens = 89,52 (1 Watt)


GTI 1000
Mechanical parameters
Fs = 62hz
Qms = 5,44
Vas = 18,97 Liters
Cms = 0,112 mm/N
Mms = 58,701 grams
Rms = 4,294 kg/sec
Xmax = 7,62 mm
Sd = 345 sq.cm
Dia = 21 cm

Electrical parameters
Qes = 0,72
Re = 2,5 ohms
Le = 0,5 mh
Z = 4 ohms
BL = 10,1 N/A
Pe = 300 Watts

Kombination parameters
Qts = 0,64
n* = 0,89%
Sens = 91,69 (1 Watt)

GTI 800
Mechanical parameters
Fs = 67hz
Qms = 4,773
Vas = 7,79 Liters
Cms = 0,123 mm/N
Mms = 45,803 grams
Rms = 4,04 kg/sec
Xmax = 7,62 mm
Sd = 211 sq.cm
Dia = 16,4 cm

Electrical parameters
Qes = 0,6
Re = 2,5 ohms
Le = 0,5 mh
Z = 4 ohms
BL = 10,1 N/A
Pe = 300 Watts

Kombination parameters
Qts = 0,533
n* = 0,56%
Sens = 89,68 (1 Watt)



All specs are from a JBL car audio brochure released in Europe around year 2000
any anomalies in the specs are probably misprints in that brochure :D

Lee in Montreal
05-18-2011, 08:35 AM
Great info. And surprinsingly, I expected a lower Fs and higher Xmas from the 1800. ;)

It looks like a 2245h remains a better option in 18"

1audiohack
05-18-2011, 09:30 AM
Not for me, I have settled with two GTI1800's in my home main. With room gain and no EQ they easily play flat down to 28-30 Hz and they are WAY tougher than 2245's, we have broken more than one of those by the way, the 1800's still feel, measure and sound as new some six years later.

That room has had 2-2241's, 2-2242's, 2&4 Sub1500's and 2,4&6 2234's and 2,4&6 2235's and the 1800's keep finding their way back as the favorites.

FE3T
05-18-2011, 02:00 PM
My interest in the GTI series was ignited by a search for an uber robust JBL midbass for use betwin a sub and up to about 1khz, therefor i wanted to research the orgin of the GTI 800 and the GTI 1000 in hope of finding a pro version with sligthly better bandwith.

I have currently the options of reconing some 2226`s for that use.
There are also a pair of LE14H-3 and 6 4612 cabaret speakers for sale relatively local, the 4612`s i can butcher for their 2118J drivers, but i am a bit unshure of using 14" or 15" for this and arent the 2118 a bit fragile for use in the 70-80hz region?

The sub octaves are already covered, it involves drivers made in USA a decade or 2 back, but not of any brand spoken of on this site, so i guess ill better not mention much about those :o:

Lee in Montreal
05-18-2011, 04:43 PM
Not for me, I have settled with two GTI1800's in my home main. With room gain and no EQ they easily play flat down to 28-30 Hz and they are WAY tougher than 2245's

Again, good info. So what would be the difference between the 1800 GTi and a good old 2240? Both have Fs30Hz, but on a different generation of basket and coils. Power handling?

Eaulive
05-18-2011, 05:26 PM
Again, good info. So what would be the difference between the 1800 GTi and a good old 2240? Both have Fs30Hz, but on a different generation of basket and coils. Power handling?

If they are based on the 2241 they have VGC technology and can handle more power.

JBL claimed that the 2241 was a direct replacement for the 2240, allowing 3dB more output in the same enclosure.
Same efficiency but more power handling.


In most applications, the 2241G/H can provide more
low frequency response, 3 dB more output and less
distortion than the 2240G/H, with little or no enclosure
retuning.From the 2241 datasheet

HCSGuy
05-19-2011, 12:26 AM
I will preface my comment with the disclaimer that I have not sold Car Audio since about when these woofers came out, and I am running off memory, so I will not defend my comments to the death, so to speak. If I remember from JBL training on these woofers, they were not designed to boom like woofers do today. In-car audio processing was much more rudimentary back then, so JBL tweaked the woofers to get flat frequency response inside the car, versus in a room. It's very different in a car, as you tend to get rising "Room" gain as frequency drops, and you don't have to worry about standing waves, as the dimensions of a car interior are smaller than 1/2 wavelength of all low bass frequencies. If you look at JBL's recommended tunings for the 1500, you will see that it would kind of suck as a home subwoofer - JBL's recommended tuning puts f3 at 38hz and falling fast. With fs of 35hz and VAS of 8 cubic feet, you're never going to get to home subwoofer territory. My experience with these was that they sounded really good installed, but didn't sell because they didn't boom - our demo space was your typical car audio sound room, which is the size of a typical home theater, not a car interior, so we didn't get the room gain JBL built into their design. The exception to this is the 1800GTI, which I've never heard, but which looks much closer to expectations for a home unit, with f3 in the high 20hz range, albeit in their recommended 12 cubic foot enclosure (Never seen a box that big in car audio). I think the 1800GTI was based off the 2240, BTW, with its shorter XMax (5.5mm for the 1800GTI and 2240 versus 7.6mm on the 2241) but I'm not going to war with anyone who feels differently. Anyway, here are links to JBL's tuning for the 1500GTI:
http://www.jbl.com/resources/Brands/jbl/Products/ProductRelatedDocuments/en-US/BoxesandParameters/1500GTI.pdf
and 1800GTI:
http://www.jbl.com/resources/Brands/jbl/Products/ProductRelatedDocuments/en-US/BoxesandParameters/1800GTI.pdf

And a snapshot of their recommended tuning for the 1500GTI:


JBL's recommended tunings for the 1500GTI

FE3T
05-19-2011, 12:04 PM
HCSGuy

1800 GTI
51374
Magnetic gap depth 8,1mm, Voice Coil Winding Depth 19,05mm in both my broshure and your link, Xmax 7,6mm in my broshure, 5,5mm in your link

2241
51375
Magnetic gap depth 8,1mm, Voice Coil Winding Depth 19,05mm, Xmax 7,6mm
Source: http://www.jblpro.com/pages/pub/components/2241.pdf

2240
51376
Magnetic gap depth 9mm,Voice Coil Winding Depth 19mm Xmax 5,5mm
Source: http://www.jblpro.com/pub/obsolete/2240gh.pdf

I belive that since the motor on the 1800 GTI looks identical to a 2241, and have the same Magnetic gap depth and both also share the same Voice Coil Winding Depth
they should also share the same Xmax, so my conclusion are that 7,6mm are probably the correct number on the 1800, 1500 and 1200 GTI`s

1audiohack
05-19-2011, 12:14 PM
I concur, for what little it's worth. ;)

hjames
05-19-2011, 12:47 PM
I did a quick web search but there doesn't look to be many of these JBL GTI 1800 speakers around
- I gather its an older model and perhaps out of production?

HCSGuy
05-19-2011, 12:58 PM
I agree - the bumped back plate is definitely 2241, not 2240.

Heather, these are long gone - I think they came out in '92-93 or so...

1audiohack
05-19-2011, 02:44 PM
When the C4RGTI1800 became obsolete, the C4R2241 kit became the option to repair them. The basket / motor assembly is absolutely identical to the 2241.

John W
05-19-2011, 09:12 PM
Here are some pictures of my 10 inch 1000GTI woofers.
It would be great if there was a way to recone them as mid drivers, like 2123.

1audiohack
05-19-2011, 09:22 PM
Oh yeah?

PM sent.

maxwedge
05-19-2011, 09:23 PM
Not for me, I have settled with two GTI1800's in my home main. With room gain and no EQ they easily play flat down to 28-30 Hz and they are WAY tougher than 2245's, we have broken more than one of those by the way, the 1800's still feel, measure and sound as new some six years later.

That room has had 2-2241's, 2-2242's, 2&4 Sub1500's and 2,4&6 2234's and 2,4&6 2235's and the 1800's keep finding their way back as the favorites.
That's a heck of a lot of woofer action there!:bouncy: That must be a pretty large room there. :rockon1:

Lee in Montreal
05-20-2011, 10:47 AM
That's a heck of a lot of woofer action there!:bouncy: That must be a pretty large room there. :rockon1:

The more subs, the less each one is stressed. :D

Eaulive
05-20-2011, 11:48 AM
The more subs, the less each one is stressed. :D

Yup, BTW we picked up another pair of 4530 for a friend of Stéphane on wednesday.
We now have four 4530, two 4520 and two CW 18" subs for the party this summer :applaud:

FE3T
05-27-2011, 09:05 AM
Seems like McKenzie have a aftermarket recone kit for the 1800 GTI.
http://reconekits.com/jbl1800gti.aspx

God news for those with a blown 1800 GTI or for those with a blown 2241 who are lusting for a 1800 GTI (sort of, depending on how close the kit are to an oem kit)

JBL 4645
07-31-2011, 12:25 PM
I did a quick web search but there doesn't look to be many of these JBL GTI 1800 speakers around
- I gather its an older model and perhaps out of production?

Doesn’t show up Google shopping looks like a discontinued model? Can’t find any listed on ebayUK ether, nor ebayUSA.

What’s JBL game they make a model then pull it out after year or so??

Lee in Montreal
07-31-2011, 01:04 PM
Doesn’t show up Google shopping looks like a discontinued model? Can’t find any listed on ebayUK ether, nor ebayUSA.

What’s JBL game they make a model then pull it out after year or so??

Isn't the 1800GTi a 15 year old product? JBL had a recone kit (C8R1800GTI) 15 years ago. Do they still have one now? If not, basically the dead baskets have probably been sent to the junkyard.

Plenty of 2241 though, which is the same basket. MacKenzie makes a recone kit if one wants to try a recone.

JBL 4645
07-31-2011, 02:34 PM
Isn't the 1800GTi a 15 year old product? JBL had a recone kit (C8R1800GTI) 15 years ago. Do they still have one now? If not, basically the dead baskets have probably been sent to the junkyard.

Plenty of 2241 though, which is the same basket. MacKenzie makes a recone kit if one wants to try a recone.

It is? I was looking around over and hour and ago and found thread on different site going back to 2009 and thought to myself it must be 2000’s model didn’t know it went back as far as late 1990’s.

No thanks I don’t want to rip my sub apart yet :D

While looking around most JBL car Hi-Fi stuff goes down to 18Hz but the upper portion is limited to 400 or 450Hz on some models JBL W12GTi not bad if used up to 450Hz then have smaller high powered JBL to handle below the range and use crossover and so on make 4 way or 5 way :D 5 way would be too costly with active crossovers and amps.

Lee in Montreal
08-15-2011, 09:13 AM
I am surprised that the 1800Gti and 1500Gti have high Fs values of 30Hz and 35Hz respectively. I would have expected at least 5Hz lower. Basically, an old and venerable 2225h could almost pass as car sub with the room gain...

I just bought an 1800gti for the sake of comparing it with my 2245.
I wonder what a set of 1500Gti would do in a 4520 scoop. The 4520 is tuned to 35Hz, which is where the 1500Gti resonates at. Basically, I suspect it has more meat from 30 to 50Hz than the 2225, and that it would help compensate for the 60-100Hz peak of the 4520. The small compression chamber can probably help in term of power handling too... Hmmmmm ;)

Eaulive
08-15-2011, 01:56 PM
I am surprised that the 1800Gti and 1500Gti have high Fs values of 30Hz and 35Hz respectively. I would have expected at least 5Hz lower. Basically, an old and venerable 2225h could almost pass as car sub with the room gain...

I just bought an 1800gti for the sake of comparing it with my 2245.
I wonder what a set of 1500Gti would do in a 4520 scoop. The 4520 is tuned to 35Hz, which is where the 1500Gti resonates at. Basically, I suspect it has more meat from 30 to 50Hz than the 2225, and that it would help compensate for the 60-100Hz peak of the 4520. The small compression chamber can probably help in term of power handling too... Hmmmmm ;)
I think it won't fit physically... too deep.

Lee in Montreal
08-15-2011, 02:02 PM
I think it won't fit physically... too deep.

1800Gti and 1500Gti are based respectively on the 2241 and 2226 baskets. Therefore they should fit. It is the later subs that have insane depth. And I mean insane.

1500gti
52471

W15gti
52472

subwoof
08-15-2011, 02:15 PM
The "scoops" are not tuned to any frequency.

The single and double just roll off at different rates and just about any driver would energize them to astounding output. Even the thin 2220/130 cones work quite well.

*if* you were worried about extreme excursion damage then maybe the 1500GTI would work well but the cone is VERY thick and therefore heavy / less efficient than the 2226.

sub

Eaulive
08-15-2011, 03:01 PM
1800Gti and 1500Gti are based respectively on the 2241 and 2226 baskets. Therefore they should fit. It is the later subs that have insane depth. And I mean insane.


Ok, you're right then, I was thinking about the latter.
Even the neodymium dual VC 2265H used in newer SR products won't fit. I checked :(

Dr.db
09-04-2011, 03:08 PM
Great discussion"" :)

I own a pair of GTI-800`s for caraudio-use. They really are great. But at home-use just a nice midbass....
Couple years ago I owned a GTI-1000 which I ran at home in a 50liter bassreflex cabinet. That actually worked quiet well.

Is there an equant to the GTI-1000 in home or pro Serie`s ??

pos
09-04-2011, 03:24 PM
Couple years ago I owned a GTI-1000 which I ran at home in a 50liter bassreflex cabinet. That actually worked quiet well.
Would you mind sharing some details about that speaker?
I have a friend that just bought a pair of GTI-1000 he plans to use with an econowave top end (selenium + PT waveguide)

1audiohack
09-04-2011, 03:35 PM
I now have the pair pictured in post #15. I have not measured them in any way yet. I stacked together a slightly larger bedroom system and just dropped the GTI1000's in a pair of .7ft3 sealed boxes with one pound of fiberglass until I get around to building some that fit in the bookcase and they sound surprisingly good just like that.

I have never seen a pro or consumer counterpart of this speaker, that surely doesn't mean there isn't though.

I'm not using them above 100 Hz but if there was something I could measure that would help you out let me know.

pos
09-04-2011, 11:43 PM
Thanks! That would be very helpful if you could measure the top end behavior, so my friend can adjust the low pass section of the econowave network knowing what he is doing (he does not have any measurement tool or knowledge, and live ~700km from here).

Did you change the dustcap, or just painted it black?

1audiohack
09-05-2011, 04:15 PM
The top line on both graphs is mic on axis, the lower line is 45° off axis. In case the small print is hard to read the top graph is frequency response the lower is phase, all from one sweep with two mic's@ 1meter. The data is rock solid down to 200Hz and believable to 100 Hz, no smoothing applied.

If this isnt what you're after let me know. I don't have my scope or Fluke at the house so I can't give you drive voltage, I will get it if you need it.

The dust caps were on them when I get them.

All the best,
Barry.

Eaulive
09-05-2011, 04:34 PM
The top line on both graphs is mic on axis, the lower line is 45° off axis. In case the small print is hard to read the top graph is frequency response the lower is phase, all from one sweep with two mic's@ 1meter. The data is rock solid down to 200Hz and believable to 100 Hz, no smoothing applied.

If this isnt what you're after let me know. I don't have my scope or Fluke at the house so I can't give you drive voltage, I will get it if you need it.

The dust caps were on them when I get them.

All the best,
Barry.

What's the purpose of having two microphones? Better averaging of dips and peaks? No need for smoothing?

Interesting curves you have, I never get them so clean unless I apply smoothing :applaud:
Of course my environment is always less than ideal.

1audiohack
09-05-2011, 05:12 PM
My measuring environment today is my driveway between rains.:bouncy: We love rain!!!

I swept this at 2000 Hz/second with a 20 Hz wide filter, not much time to include noise. Anechoic by definition to 150 Hz.

The mic off axis is for indicating directivity.

pos
09-05-2011, 11:55 PM
Thanks a lot Barry!!

That broad 5dB peak at 650Hz will have do be delt with in the passive crossover, as the crossover point will probably be around 1200Hz :hmm:
How large is the baffle (to assert the baffle step) ?

Thanks again, that is very helpful :bouncy:

1audiohack
09-06-2011, 06:59 AM
Hi Thomas;

The baffle on this test box is almost nonexistent at only 10 high and 11 inches wide. It was measured 2M above ground in free space. If something else would be helpful please let me know.

All the best,
Barry.

mtchyz250f
12-08-2011, 12:27 PM
What is the top end extension of the 1500Gti, 100, 200, 400hz?

grumpy
12-08-2011, 12:35 PM
the spec sheet claims a frequency response of 20Hz-300Hz ...
likely insufficient information to be of much use,
but it matches up with dimensionality of the question.

http://www.jbl.com/resources/Brands/jbl/Products/ProductRelatedDocuments/en-US/BoxesandParameters/1500GTI.pdf

mtchyz250f
12-09-2011, 07:05 AM
Thanks grumpy. But I find those to be very optimistic in most cases. Specifically do you think in can be used to 200Hz?

grumpy
12-09-2011, 07:14 AM
Keeping in mind that the impedance drops quite low,
-if- you're actively crossing over and the amp is up to it,
then sure... 200Hz would probably still work OK.

If what you're intending to cross them over to can handle
lower frequencies, it would be worth trying.

Keep in mind the the driver was designed as a subwoofer,
not a mid-bass driver.

mtchyz250f
12-09-2011, 08:03 AM
Thanks again grumpy. I appreciate your patience with me. Let me get into the application a little more to save some time. I have a friend who teaches music part time and wants a simple and inexpensive system for critical listening. He has an old SoundStream Rubicon 5ch amp with built in 12 db active crossovers.

My thinking was with the GTI he would get great sensitivity needed for the low power amp and be able to cross to the OEM door speakers a little higher so as not fry them when he turns the volume up a little; while still getting great sound. Later he can upgrade the door speakers to something a little better. Do you think the GTI is the right speaker, is my thinking correct?

Thanks again for your time.

grumpy
12-09-2011, 08:32 AM
one of the 5ch amps with a dedicated sub channel (more power on the sub amp)?

If you want efficiency, go for the vented example in the pdf, I prefer the sealed
sound, but it takes more power to drive it (up to 10x at 50Hz)... and I'm not a
"boomer" :)

I'd still recommend going lower in the crossover frequency if you can... the JBL
box examples are using 70Hz for a smooth-ish blend and crossover. So somewhere
between there and 100Hz is what I would be trying. You'll also likely need to adjust
the levels between the sub channel and the others... hopefully there are controls
on the amp for that.

All that said, the GTI sub is massive overkill for pairing up with a set of stock
in-door drivers, but that shouldn't stop you from having some fun.

Cheers.

mtchyz250f
12-09-2011, 09:41 AM
Thanks grumpy, that is everything I needed to know.

Lee in Montreal
12-09-2011, 09:45 AM
BTW I have a 1800GTi and found that anything above 100Hz was pretty muddy. It'll be used as a 2 octave driver. 20-80Hz.