Vintage 6" fullrange, Philips AD2700M

[IG81]

Hi there,

I post this as a way to get some info out there on these drivers I pulled from a Philips console, since I found practically no valuable info on them online.

Model is Philips AD2700M, 6" paper cone and suspension, with whizzer cone, AlNiCo motor and octogonal frame.

4 drivers.jpg

driver front.jpg

driver back.jpg

Here are the T/S parameters I measured, averaged from the 4 drivers:

Znom 4 ohm
Re 3,2 ohm
Fs 78 Hz
Qms 2,61
Qes 1,38
Qts 0,9
Vas 20,09 l
Sd 126 cc
SPL 90 dB
BL 2,32 N/A

I'll first try them on test open baffles to see if I like their sound to know if I should go further with a more serious build, but their high Q might limit me.

If anyone has some experience with similar Philips fullrangers, I'd like to hear about it, thanks.

Best regards,

IG

[chris661]

Hmmm...

I've seen a couple of designs where a vintage wide-range driver is supplemented by a super-tweeter and a 15" bass driver on OB. Works well, as the crossovers aren't in the sensitive human hearing area.

[grantnsw]

Try this site: mfbfreaks : Official Site
in the drop-down box 'Luidsprekers' then Passief then Speaker Info,

if no luck, try their forum. They are very helpful if you google translate into Dutch.
cheers, Grant

[IG81]

Originally Posted by chris661

Hmmm...

I've seen a couple of designs where a vintage wide-range driver is supplemented by a super-tweeter and a 15" bass driver on OB. Works well, as the crossovers aren't in the sensitive human hearing area.

Yes, that is a possibility for me. I have two Foster 12" from Sears Professional boxes I trashed, but I measured their Qts (0.55) to be lower than what others have measured (~0.69). Might still work, but I'd wish for something closer or above 1.00. But that's what OB's are great for, cheap cheap cheap experiments!

The only way I tried them so far was in the 2.34 liter box I built to measure Vas and, although bass was severely rolled of with an f3 of ~220Hz, they sounded promising for mids and highs.

Originally Posted by grantnsw

Try this site: mfbfreaks : Official Site
in the drop-down box 'Luidsprekers' then Passief then Speaker Info,

if no luck, try their forum. They are very helpful if you google translate into Dutch.
cheers, Grant

Yes I did already check out that site. My drivers predate the papers they have online though. I might try to look into the forums for fun, as I did not do that yet, thanks!

IG

[planet10]

Originally Posted by IG81

I have two Foster 12" from Sears Professional boxes I trashed, but I measured their Qts (0.55) to be lower than what others have measured (~0.69). Might still work, but I'd wish for something closer or above 1.00.

When i was doing mostly vintage stuff people would be looking for this philips for OB use.

The Foster 12" is a nice driver. My measures, IIRC, give me a Qt similar to yours sample size >10 units). These should work well in a ripole. (my plan for Foster attached)

dave

[IG81]

Originally Posted by planet10

When i was doing mostly vintage stuff people would be looking for this philips for OB use.

The Foster 12" is a nice driver. My measures, IIRC, give me a Qt similar to yours sample size >10 units). These should work well in a ripole. (my plan for Foster attached)

dave

Hi,

I'll be putting the Philips in quick and dirty OB's tonight hopefully to see what they can do.

You mentionned the Ripole application for the Foster's in the dedicated thread I had a while back, which I might end-up doing. I wanted to measure them before I do anything, which I only did last weekend (still have to build a box for Vas...). I'll have to see if it's better to fill the bottom end with a Ripole or mount them in the same OB as the Philips, but chances are I'll do the Ripole, since I don't have much room, especially not for 3' wide OB's. That and their not quite-suitable Qts.

IG