I have two 2 cu ft cabs and two 300w plate amps and always figured drivers would come my way at some point in time. Well, I was at a friends house last weekend and he asked if I want two speakers. I assumed he meant speakers in cabs but instead he handed me to JBL GT1041D sub drivers new in the box.
They are car subs so I assumed they might not work in a home system. I did a WinISD this morning and found that they actually might work very well. Here is a screen shot of the Win results and the PDF for the drivers.
Your thoughts???
They are car subs so I assumed they might not work in a home system. I did a WinISD this morning and found that they actually might work very well. Here is a screen shot of the Win results and the PDF for the drivers.
Your thoughts???
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If the Group delay gets to high it can give the low end a muddy or slow as some put it kind of sound.
I don't know exactly how low is good.
But, I typically shoot for 1/2 to 1/4 or lower ms than what the peak frequency is as long is it doesn't hurt my target lowest frequency much.
For 30HZ is 33ms so I try to get below 15ms to 7.5ms as long as the frequency response doesn't hurt to much at this end of the scale.
This is a very hard decision and requires a lot of compromise.
But you can also consider room gain to help compromise for the drop.
I built my 8" subs (optimus CWS-PRO800) in a small .67cu' box like a sealed but then I added a port tuned very low at bout 22Hz to 25Hz.
This added about 2db or so bump/shelve to the extreme low end compared to that of a sealed box.
In my car with the cabin gain this flattened out the response quite nicely and a pair of them really rocked
The bass was nice and tight with no boominess at all.
Kick drums and toms were Awesome!
Later on I used that same sub in my room with my little ESL panel and it matched up perfectly with it as well.
I tried that same little panel with various commercial Hi-Fi cabinets that I have around the house and they didn't match up well.
Including my little Sony 5 1/4" speakers until I sealed up the port and then the melded as one, I couldn't believe it.
Some like the sound of ported boxes and I used too back in the day when good deep bass was hard to come by.
Lately I am liking more the transient response that sealed box or what a small low tuned box has to offer.
Sort of like the dampening that TL's can offer as well, although I have yet to try one out.
Lately I have been studying up on the Aperiodic enclosures as well.
What Roger Sanders said in his paper made a lot of sense to me and I relate this to my own findings,
An Interview with Roger Sanders of Sanders Sound Systems - The Columns - Dagogo
It is always the subject of having a deep and low bass extension but for what cost when it comes to music?
In the plot you had posted by tuning it a bit lower you can reduce the group delay quite considerably to about 10ms at 40 hz and this might bring the peak of the curve at about 25hz to 30hz.
I will enter the data into Winlsd and check it out later tonight.
But I definitely think that you can have a really decent sub system with those drivers.
It had been quite a while since I have looked at the JBL website but these kinda caught my eye as impressive yet affordable as well,
GT5-12 | 12? single voice coil subwoofer | JBL US
this has a higher power handling as it cost more,
GTO1214 | 12? die-cast, 4-ohm voice coil subwoofer | JBL US
I think you scored a pair of really nice drivers there !!!
Cheers !!!
jer
I don't know exactly how low is good.
But, I typically shoot for 1/2 to 1/4 or lower ms than what the peak frequency is as long is it doesn't hurt my target lowest frequency much.
For 30HZ is 33ms so I try to get below 15ms to 7.5ms as long as the frequency response doesn't hurt to much at this end of the scale.
This is a very hard decision and requires a lot of compromise.
But you can also consider room gain to help compromise for the drop.
I built my 8" subs (optimus CWS-PRO800) in a small .67cu' box like a sealed but then I added a port tuned very low at bout 22Hz to 25Hz.
This added about 2db or so bump/shelve to the extreme low end compared to that of a sealed box.
In my car with the cabin gain this flattened out the response quite nicely and a pair of them really rocked
The bass was nice and tight with no boominess at all.
Kick drums and toms were Awesome!
Later on I used that same sub in my room with my little ESL panel and it matched up perfectly with it as well.
I tried that same little panel with various commercial Hi-Fi cabinets that I have around the house and they didn't match up well.
Including my little Sony 5 1/4" speakers until I sealed up the port and then the melded as one, I couldn't believe it.
Some like the sound of ported boxes and I used too back in the day when good deep bass was hard to come by.
Lately I am liking more the transient response that sealed box or what a small low tuned box has to offer.
Sort of like the dampening that TL's can offer as well, although I have yet to try one out.
Lately I have been studying up on the Aperiodic enclosures as well.
What Roger Sanders said in his paper made a lot of sense to me and I relate this to my own findings,
An Interview with Roger Sanders of Sanders Sound Systems - The Columns - Dagogo
It is always the subject of having a deep and low bass extension but for what cost when it comes to music?
In the plot you had posted by tuning it a bit lower you can reduce the group delay quite considerably to about 10ms at 40 hz and this might bring the peak of the curve at about 25hz to 30hz.
I will enter the data into Winlsd and check it out later tonight.
But I definitely think that you can have a really decent sub system with those drivers.
It had been quite a while since I have looked at the JBL website but these kinda caught my eye as impressive yet affordable as well,
GT5-12 | 12? single voice coil subwoofer | JBL US
this has a higher power handling as it cost more,
GTO1214 | 12? die-cast, 4-ohm voice coil subwoofer | JBL US
I think you scored a pair of really nice drivers there !!!
Cheers !!!
jer
I was Messing with Winlsd and I must say that driver models nicely.
Here is what I have with it modeled in a 2 cubic foot ported box at 22.4Hz and 200 watts.
The port is set at a conservative 3.23" dia. and is 18.71" long as this would just fit in a box with 1' X 1' X 2' internal dimensions.
105 db at 20Hz and 110 db at 80Hz that is about a 2.5 db per octave slope....Nice !!!
It works nicely in a range of about 1.5 to 3 cubic feet for a ported and 1 cubic foot for a sealed.
Four of those would suit me very well as I do need to start building a new bass system soon.
My old drivers have now seen their better days...He,he,he,he!!!
Enjoy !!!
jer
Here is what I have with it modeled in a 2 cubic foot ported box at 22.4Hz and 200 watts.
The port is set at a conservative 3.23" dia. and is 18.71" long as this would just fit in a box with 1' X 1' X 2' internal dimensions.
105 db at 20Hz and 110 db at 80Hz that is about a 2.5 db per octave slope....Nice !!!
It works nicely in a range of about 1.5 to 3 cubic feet for a ported and 1 cubic foot for a sealed.
Four of those would suit me very well as I do need to start building a new bass system soon.
My old drivers have now seen their better days...He,he,he,he!!!
Enjoy !!!
jer
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The slight drop is caused by a lower tuning in order to lower the group delay to 12ms at 30Hz.
Here is a comparison of three different tunings,
Winlsd's optimised= blue
My tuning = yellow
My tuning flat= orange
I should have added JBL's tuning for comparison as well.
The drop in response will be compensated by room gain and most likely will be quite flat when measured in the room if not a slight boost depending on the size of your room and its loss factor.
You can also have a more flatter response by increasing the box slightly to 2.3 cubic feet tuned to 27.5 Hz with an added .33 ohm series resistor as shown in the last two pictures in green.
This also raises the group delay considerably as well,almost double at 22.974ms !!
Remember that at 30hz a 33ms of group delay is a full wavelength of delay !!
jer
P.S all of the simulations are for the JBL GT-1041D that you originally posted and not the GT5.
Here is a comparison of three different tunings,
Winlsd's optimised= blue
My tuning = yellow
My tuning flat= orange
I should have added JBL's tuning for comparison as well.
The drop in response will be compensated by room gain and most likely will be quite flat when measured in the room if not a slight boost depending on the size of your room and its loss factor.
You can also have a more flatter response by increasing the box slightly to 2.3 cubic feet tuned to 27.5 Hz with an added .33 ohm series resistor as shown in the last two pictures in green.
This also raises the group delay considerably as well,almost double at 22.974ms !!
Remember that at 30hz a 33ms of group delay is a full wavelength of delay !!
jer
P.S all of the simulations are for the JBL GT-1041D that you originally posted and not the GT5.
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I have a pair of these JBL GT1041D. I must say they are one of the best 10" "car" subs that work well for home hifi. Tested them in 25 Liters (0.9 cu ft) ported boxes. Great dynamic/punchy mid-bass. They do go down low too, so low bass is not a problem.
It's always difficult to get the right balance. Often times, we get too caught up with either low bass extension or lowest F3. After building the speakers, we find that they sound lifeless. That's due to the lack of mid-bass. Nowadays, I would rather sacrifice a little bit of low bass in exchange for superior mid-bass.
Regards
Mike
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Here is the same charts but the JBL's tuning added.
Big difference but still acceptable for music (I guess).
IMHO I would take the drop in response and let room gain compensate for it.
And a lower bass extension with a lower group delay at 30Hz for music use as well.
Were as my tuning shows a 4Hz lower response at 26.3Hz for the same delay.
The JBL tuning is not bad as well as I didn't even look at it until now.
But I personally don't really consider anything below about 25hz to 30hz to be of any use for music although some do.
Cheers !!
jer
Big difference but still acceptable for music (I guess).
IMHO I would take the drop in response and let room gain compensate for it.
And a lower bass extension with a lower group delay at 30Hz for music use as well.
Were as my tuning shows a 4Hz lower response at 26.3Hz for the same delay.
The JBL tuning is not bad as well as I didn't even look at it until now.
But I personally don't really consider anything below about 25hz to 30hz to be of any use for music although some do.
Cheers !!
jer
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I would Like to see some THD measurements of this driver if anybody has some they would like to post.
Or any of the other JBL series as well.
I was going to get some of GTO 1204's or 1214's back a few years ago and now I wish I had, As inflation has really taken a hit on raw drivers lately.
jer
Or any of the other JBL series as well.
I was going to get some of GTO 1204's or 1214's back a few years ago and now I wish I had, As inflation has really taken a hit on raw drivers lately.
jer
Thanks for your work Jer, it looks like these will work very well for my purposes. I don't do HT so it is music only and these will actually be 3rd and 4th subs in the room. When Joe handed me these, I took them to be polite.....I'm glad I did!
P.S., you should stop by if you are ever in Waterford area. Cheers, Dennis.
P.S., you should stop by if you are ever in Waterford area. Cheers, Dennis.
Cool, Thanks Dennis, if you are ever out here in the Jackson area feel free to get a hold of me in a PM and I will give you my info.
And we can visit and show you my setup as I can't drive at the moment.
I think those subs will work nicely.
I had 4 x 12's and 4 x 10's going of some average speakers but sadly I just lost 3 of the 12's.
It would reach 110db tight and clean when it all was working right.
Here is a picture of my system after I had just rebuilt it.
I don't have any big ESL's made yet.
jer
And we can visit and show you my setup as I can't drive at the moment.
I think those subs will work nicely.
I had 4 x 12's and 4 x 10's going of some average speakers but sadly I just lost 3 of the 12's.
It would reach 110db tight and clean when it all was working right.
Here is a picture of my system after I had just rebuilt it.
I don't have any big ESL's made yet.
jer
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I would be interested in them however I am not working still.
I have been building my own for quite some time, only I just haven't made any larger ones yet.
Right now I am concentrating on perfecting my desktop model and then I will be applying all of what I have learned into some that will fit the stack.
jer
I have been building my own for quite some time, only I just haven't made any larger ones yet.
Right now I am concentrating on perfecting my desktop model and then I will be applying all of what I have learned into some that will fit the stack.
jer
COOL!!! I have been going back and forth about these ESL panels. I know I can build the power supplies no problem, but my new room is small and the panels are large....and, I just finished my horns in May and just got a pair of Lambda woofers to replace the JBLs I have now.
I would like to hear your desktop ESLs sometime.
I would like to hear your desktop ESLs sometime.
I had though you had all ready got those running.
After I finish my desktop model I will focusing on a medium sized application just to suit the needs of situations like yours.
I am thinking of two sizes in the 2 foot and 4 foot tall range and my bigger ones will be 6' to 8' tall.
They will be of a hybrid design so that the won't have to be so wide.
I am also starting to play with electrically segmenting them as this will help to widen their horizontal dispersion.
From what I have read this works very well as the wider the panel gets the more directional they become.
Here is a picture of my latest mini panel.
It is 12 inches tall and 5 inches wide.
All that is needed is to mount the diaphragm and get the resistors needed for the segmentation.
I will be having a First test of this one some time this week.
jer
After I finish my desktop model I will focusing on a medium sized application just to suit the needs of situations like yours.
I am thinking of two sizes in the 2 foot and 4 foot tall range and my bigger ones will be 6' to 8' tall.
They will be of a hybrid design so that the won't have to be so wide.
I am also starting to play with electrically segmenting them as this will help to widen their horizontal dispersion.
From what I have read this works very well as the wider the panel gets the more directional they become.
Here is a picture of my latest mini panel.
It is 12 inches tall and 5 inches wide.
All that is needed is to mount the diaphragm and get the resistors needed for the segmentation.
I will be having a First test of this one some time this week.
jer
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If you are talking about the horns, yes, they've been up and down again. I made legs for them and they are out at the copper coater for copper platting. Those panels look very nice. The only experience I have with ESLs are my buddies top of the line SoundLabs. I don't have that kind of money.
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