Woofer suggestions for Lampizator OB project

[rockymystic]

Hi,
I am building my first ever DIY project aka Lampizator P17. I have accquired the greencones from ebay and now i am looking for good woofers. Vintage woofers are near around 400$ plus shipping which are not in my price range.

Can someone suggest other woofers than can be used.? I have seen people using eminence alpha 15A. But have also read that they really don't sound good.

Are they any other nice woofers that can be used in this Open Baffle Design?

here are the specs mentioned in the website.
BASS: any bass of size 15 or 18 inches. Maximum value Fs is 37 Hz, optimal is 25.
Maximum Qts is 1, optimum is 0,35
Minimum sensitivity dB/1m/1W is 97 dB

 

[adason]

check out Troels Gravesen's web page for OB woofer suggestion...
OBL11

 

[rockymystic]

check out Troels Gravesen's web page for OB woofer suggestion...
OBL11

Thanks, But seems Eminence DeltaLite II 2515 would still be around 400$ a pair that would be same as the vintage altec ones which lukas suggests.. any other suggestions?

 

[zmyrna]

The Chinese woofers that Lukasz used in his budget builds are widely available under different labels and they are cheap. And instead of the deep U baffle Lukasz suggests, you may try to go Cardioid for the woofer (shallower U and some absorptive material to absorb the back wave).

 

[zmyrna]

UK version
Soundlab 15" Black High Quality 300W 8 Ohm Bass Speaker
French seller
Haut Parleur Basse Soundlab 38 cm 400W 8 ohms Haute Qualite Electrovision

 

[rockymystic]

Hi zmyrna,
Seems they are in UK and France couldn't find one in USA :-(

 

[komigenie]

Maybe this one ...


$64.99


Eminence Speaker ALPHA-15A
15" Woofer for PA

Nominal Basket Diameter 15", 381mm

Nominal Impedance* 8 ohms

Power Rating**

Watts 200W

Music Program 400W

Resonance 41Hz

Usable Frequency Range 46Hz - 3.5kHz

Sensitivity*** 97dB

Magnet Weight 25 oz.

Gap Height 0.25", 6.35mm

Voice Coil Diameter 1.5", 38.1mm

Mounting Information

Recommended Enclosure Volume

Sealed 71-85 liters / 2.5-3 cu.ft.

Vented 106-177 liters / 3.75-6.25 cu.ft.

Driver Volume Displaced 195.9 cu.in. / 3.21 liters

Overall Diameter 15.15", 384.8mm

Baffle Hole Diameter 13.87", 352.3mm

Front Sealing Gasket Fitted as standard

Rear Sealing Gasket Fitted as standard

Mounting Holes Diameter 0.25", 6.4mm

Mounting Holes B.C.D. 14.56", 369.9mm

Depth 5.83", 148mm

Net Weight 6.7 lbs, 3 kg

 

[rockymystic]

Hi komigenie,
I am aware of eminence alpha, but was looking for some other woofers...seems ppl have mixed opinion about alpha speakers.

 

[rockymystic]

check out Troels Gravesen's web page for OB woofer suggestion...
OBL11

Does using eminence 2 delta requires a change in crossover design?

 

[komigenie]

Hi komigenie,
I am aware of eminence alpha, but was looking for some other woofers...seems ppl have mixed opinion about alpha speakers.

Well, dunno really what you want ... there is good but cheap solution ....

 

[DeonC]

I want to ask a question that is related, but different. I am also thinking of building a P17, but want to use the woofers I have (10" and 12" HE woofers). I want to use them in parallel, which makes the woofer impedance 4-ohm, not 8-ohm. What changes do I need to make to the XO for the bass? AFAIK, if you go to 4-ohm from 8-ohm, you halve the inductance and double the capacitance. So for the P17 XO, that standard XO values are 4.7mH and 68uF for the 8-ohm woofer. So, for a 4-ohm woofer, do the values change to 2.35mH and 136uF?

Lampizator Endorphin P-17 speaker XO:

 

[rockymystic]

check out Troels Gravesen's web page for OB woofer suggestion...
OBL11

Thanks everyone,
Although eminence deltalite seems costly i got used ones for cheap, they are being shipped right now...

 

[adason]

So, for a 4-ohm woofer, do the values change to 2.35mH and 136uF?

Yes