precision devices pd 1550

[back]

i am planing to use this driver 40hz-200hz at bass reflex enclosure.

people say that low qts drivers are meant for horn loading but the

datasheet says it will work for bass reflex too.

i don`t mind using some eq to make it flat.

is there any other flow except that?

i believe the cone control will be awesome because of the very high bl.

is there a reason i shouldn`t use it that i can`t see?

how many litters and tuning would you recommend?

george.

 

[djk]

The Qts is too low for good performance in a vented box.

Fs 31 Hz
Xmax 8 mm
Revc 6.4 Ohms
Vd 7x10-4 m3
Qts 0.21
No 3.14%
Qms 5.55
Pmx 600 Watts
Qes 0.22
Cms 215 µM/N
Vas 242 Litres
Mms 123.4 grams
Sd 890 sq cm
BL 26.34 T/m

But if you want to try it, build a 140L box and tune it to 40hz.

 

[tinitus]

well, PD1550 is cheap right now because of new model
with EQ its probably a fantastic woofer
but that takes power
the new model does have higher Qts
but hifi, I guess the 18" PD186 could be a better choice, and still affordable

and btw, I think EQ is best done with closed designs

 

[tinitus]

how many litters and tuning would you recommend?

george.

its easy to find find software, and not very difficult to use
its more difficult to 'predict' the actual sound

 

[Rojoh]

If you haven't bought drivers yet, I can recommend the neo-15 from PD: The PDN-15BR40. Very nice soundig driver for BR.

Fs 35.678 Hz
L1 0.820 mH
L2 1.851 mH
Res 79.625 Ohms
RMSE-load 1.945 Ohms
Qts 0.338
RMSE-free 0.430 Ohms
Qms 5.727
Vas 224.800 Litres
Qes 0.359
Mms 90.949 grams
Sd 855.35 Sq Cm
Cms 218.797 µM/N
R2 5.017 Ohms
BL 16.836T/m
Xmax 10.5 mm
Re 5.106 Ohms

The PD-186 is also a good (and bigger) driver for BR.

 

[back]

pd 186 looks very good.

i couldn`t find price for pdn15br40

 

[tinitus]

I reckon all the PD neo woofers are more less obsolete by now
the PD 186 may have been obsolete as well
could be there have been a 'demand' for it

among the PD woofers, the PD186 has pretty good Xmax
probably why its at the lower end of the SPL efficiency scale
which btw often gives better low end efficiency
strange upsidedown logic

 

[chris661]

A variable output impedance amplifier would enable you to increase Qes (and thus Qts) to be more usable.
Download winISD Pro and play with the Added Series Resistance to get it right.

 

[back]

it seems that pd1550 is doing well at 110L 40hz.

it needs only 3db boost 40-70hz (40hz is fine for me) and with the room placement

maybe no eq at all and can give 118db at 1m.

i think i will give it a try because pd 186 results to very big box.

 

[bjorno]

Hi, FYI:

b

 

[tinitus]

i am planing to use this driver .....
george.

me too
and beat the crap out of it with seriously heavy cone modding/coating
my first subwoofer

hey, back, how did it go with your project ?

 

[tinitus]

........ cone modding/coating

well, I got 'second thoughts', and looked at better options

but yesterday I spotted a new software tool
it calculates new Fs and Qts values

lets try adding 100gr mass to the original mms 125gr of the PD1550
with the lowish original mms it gives
should result in Fs 23hz and 0.28 Qts, and 94db SPL

a real heavyweight pro woofer with those specs, isnt that just cool

 

[tinitus]

tried to ad 100gr mass to the PD186
interesting driver for this because it already have relatively low Fs, and highish Qts
aiming at closed box, ofcourse

same thing as the PD1550
only difference, the PD186 does it in a closed box
150 liter, -3db/40hz, -6db/30hz
nice

now thinking about how best to ad exstra mass

 

[tinitus]

wondered how much 100gramme is
and this is what it is

 

[tinitus]

Ps:

In another thread we talked about adding cone weight to a PD.1550 and
PD.186 in order to increase the Qts, thus making these speaker drivers to suit HiFi subs:
Ive lost track of the original thread but posting my suggestions here instead.
Very high quality performance can be attained if using driver with exceptional low distortion and quality spider systems like the PD's have by keeping the added cone-weight not exceeding the nominal values.
IMO only rugged drivers (low nominal cone-weights to start with) with known or documented low distortion should be candidates.
Picture#2:

moved from another thread


moderation

 

[tinitus]

hey, bjorn, did you notice I posted about a new simple software calculating new Fs and Qts specs when adding mass
makes quite a difference, being ably to do it correctly

 

[bjorno]

hey, bjorn, did you notice I posted about a new simple software calculating new Fs and Qts specs when adding mass
makes quite a difference, being ably to do it correctly

tinitus,

Thank you for moving my picture and text.

Where can I find this software?

b

 

[tinitus]

www.mh-audio.nl

 

[back]

me too
and beat the crap out of it with seriously heavy cone modding/coating
my first subwoofer

hey, back, how did it go with your project ?

i wasn`t following this thread after so match time and i just saw this.i went with jbl gti 1200 car subwoofers.

great bass.

 

[tinitus]

maybe we have to continue without you then