Hello,
Few weeks ago the Audio Lab DQ40TZF-02 drivers i ordered arrived, but have been nuts too to try them. So finally yesterday I had couple of hours spares and made a pair modest 18mm ply 260x150mm baffle boards for them. Now i realize the baffle boards are small but i must admit that i am really disappointed with the sound from them, also they seem to required quite a lot of power to get even modest volume from them compared to a pair of old BR 5" missions.
Single piano notes maybe not too bad, but speech and multiple instrument is just a jumble.
So I am wondering are these drivers truly that bad and not worth building proper cabinet for, or is this test simply invalid considering the modest size of the baffle boards?
Many thanks IMK
Few weeks ago the Audio Lab DQ40TZF-02 drivers i ordered arrived, but have been nuts too to try them. So finally yesterday I had couple of hours spares and made a pair modest 18mm ply 260x150mm baffle boards for them. Now i realize the baffle boards are small but i must admit that i am really disappointed with the sound from them, also they seem to required quite a lot of power to get even modest volume from them compared to a pair of old BR 5" missions.
Single piano notes maybe not too bad, but speech and multiple instrument is just a jumble.
So I am wondering are these drivers truly that bad and not worth building proper cabinet for, or is this test simply invalid considering the modest size of the baffle boards?
Many thanks IMK
Putting a pair of 4" drivers on a baffle the size of a cutting board, and comparing them to a pair of commercial vented boxes with 5" woofers. That was bound to be a failure.
Get the T/S or better yet measure the drivers, make whatever you plan to do with them, but make it right.
Last thing, the QC on these Chinese drivers is hit or miss. You might get a pair that is well put together, or not.
But before blaming the drivers, give them a chance to perform in the right settings.
Get the T/S or better yet measure the drivers, make whatever you plan to do with them, but make it right.
Last thing, the QC on these Chinese drivers is hit or miss. You might get a pair that is well put together, or not.
But before blaming the drivers, give them a chance to perform in the right settings.
I'd take the TS found online with a (huge) grain of salt. These things vary quite a bit within the same production.
Many thanks for all the inputs.
After bit of searching i found this How to measure Thiele Small parameters using your SOUND CARD - YouTube
So seems fairly easy to measure these DQ40TZF-02 so think i'll run em in for a few hours and get setup to get the TS data. BTW I wrapped a pair of hand towels over the back of the driver/baffle boards and they sound much better, I guess it is stopping the rear sound killing the front sound. Onward and upwards.
When i get the TS's I'll publish them on this thread. All i need to find is a 100R in my bits box and big lump of Blue Tack 🙂
After bit of searching i found this How to measure Thiele Small parameters using your SOUND CARD - YouTube
So seems fairly easy to measure these DQ40TZF-02 so think i'll run em in for a few hours and get setup to get the TS data. BTW I wrapped a pair of hand towels over the back of the driver/baffle boards and they sound much better, I guess it is stopping the rear sound killing the front sound. Onward and upwards.
When i get the TS's I'll publish them on this thread. All i need to find is a 100R in my bits box and big lump of Blue Tack 🙂
+1^10 at that price point/pr.
That said, is the whizzer some type of plastic as it sure looks like it in a blow-up?: 2pcs/lot Sounderlink Audio Labs Top end 4 inch Full Range monitor Speaker tweeter woofer Aluminum Bullet 2 Layer kapton Cone - Sounderlink professional pro drivers and speakers
Also, really need the $0.98 tweak with whizzers in general and especially with such small drivers: Modifications
GM
That said, is the whizzer some type of plastic as it sure looks like it in a blow-up?: 2pcs/lot Sounderlink Audio Labs Top end 4 inch Full Range monitor Speaker tweeter woofer Aluminum Bullet 2 Layer kapton Cone - Sounderlink professional pro drivers and speakers
Also, really need the $0.98 tweak with whizzers in general and especially with such small drivers: Modifications
GM
Put them in a closed 7-8L with a bit of damping material and eventually some serial inductivity against the baffle step and rise in treble.
81.6dB - baffle step gives you a mere 76dB/W, but good quality 100Hz f3
probably operating the speakers without box has the coil bumping against the pole plate creating this distortion, hope they are not killed already
81.6dB - baffle step gives you a mere 76dB/W, but good quality 100Hz f3
probably operating the speakers without box has the coil bumping against the pole plate creating this distortion, hope they are not killed already
I agree that a basic sealed box with stuffing and a BSC will let you know how the mids and highs sound and if worth pursuing into a vented box. Foam core or even a shoe box and tape is better than nothing.
Hello and again many thanks for all the useful input.
I have used three apps to do the seal box sizing and 7.9lt seem to do it.
I think/hope i have not damaged them as only used very low power of couple of watts or so and no major cone movement.
I like the idea of the foam cone infill, looks fairly easy and reversible so high on my list of thing to try and tweak.
I have model the box in Alibre Design and exported it as 3D PDF that i have attached. Click on it and you should be able to rotate it about.
Going to be a week or so before i have made the enclosures as need sort the router table for the rebated joints. Best excuse I have had in long time to get the carpentry tools out 🙂
again thanks for all the help, real nice forum this. 🙂
I have used three apps to do the seal box sizing and 7.9lt seem to do it.
I think/hope i have not damaged them as only used very low power of couple of watts or so and no major cone movement.
I like the idea of the foam cone infill, looks fairly easy and reversible so high on my list of thing to try and tweak.
I have model the box in Alibre Design and exported it as 3D PDF that i have attached. Click on it and you should be able to rotate it about.
Going to be a week or so before i have made the enclosures as need sort the router table for the rebated joints. Best excuse I have had in long time to get the carpentry tools out 🙂
again thanks for all the help, real nice forum this. 🙂
Another possibility is to make a 2,8L closed box (f=133Hz, Q=1) and put a bipolar series Capacitor of 620uF (2x220u + 180u).
The lower f3 will now be 94Hz.
Not so bulky, more power, subsonic filter included
The lower f3 will now be 94Hz.
Not so bulky, more power, subsonic filter included
Bansuri, many thanks for the idea would be ideal solution for the PC speaker solution i have in mind. But why use (2x220u + 180u) as 620uf is a preferred value and available off the shelf at Farnells, RS, Mouser etc.
Or I have missed something please?
imk
You have to consider 1,5 times your amp voltage, so for a 100W amp the caps should withstand 30Vrms. or 100Vdc,
with 40W or less the the 50V will do
It is also better to have several in parallel for higher current capability and cooling.
Capacitors
with 40W or less the the 50V will do
It is also better to have several in parallel for higher current capability and cooling.
Capacitors
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I think for a back to back cap as bipolar high pass, the DC voltage rating is not related to the max AC swing of the amp. The DC offset of most amps is very close to 0v and the AC variations can be much higher than the DC rating.