Philips AD70850 M8


I have bought for 15$ a pair of Philips AD70850 M8.

Does somebody have any experience with this driver or have the specifications ?

Best Regards



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AD70850M8 partial spec

Hi Pascal,

For $15, it was a nice buy.

I have the full spec at home, here are some for the start:
70 - Frame size 7"
850 - ceramic magnet nominal dia 45mm
M - Smooth response over a wide frequency range
8 - 8 ohms impedence
Freq response : 105Hz
Freq Range : 60 to 20K
Core dia : 14.5mm
Power Handling : 7W
Mounting Depth : 61.5mm

email me if you r interested for the fullspec.

Hi guys,

I don't know because I have not heard one of these taiwanese drivers, but I do think philips drivers are truly a great deal.

I will try to explain : (even if I'm the one who sold these drivers to Pascal, you may laugh but I really think what I say :angel: )

You can say of most philips vintage drivers that :

They are cheap (even prices are increasing on ebay)
They are made with very light and rigid paper cones
They sound clear whith detailed highs and clean fast bass.

I currently own the Philips AD4200M that is a 12 inch alnico driver with treble cone.

I listened PHY hp (FRENCH !!!) 12 inch alnico drivers with coax tweeters last saturnday. These PHY are around 2000$ the pair.

Even if they are top of the line fullrangers made by a french (my country) maker, THEY WERE NO MATCH WITH MY AD4200M !

Think of it.

PS : I sold these little fullrangers to Pascal for 15$ the pair and shipping included, I don't think there is any driver in the world you can get for the same price which can sound as good
Originally posted by qwad
:D dont waste your time with philips drivers there are better cheap drivers out there from taiwan that would run rings around any philips driver....;) just my 0002cents worth cheers TC

how ironic...
I do have some old fullrange units from Philips at home.
A 12" , the famous 9710m and a 51/2" driver (don't know the snr.)

I measured all of them and was REALLY surprised with the smal 51/2"fullrange unit. It performs up to 20khz with a nice freq. response and the decay diagram is superb (it's as good as the top models of todays leading fullrange manufacturers!).
You can't see any resonances at the decay diagram, a sign for a good membran! it's just plain old paper, but very stable.

Like someone said before, all of the units I have at home sound very open and clear. I haven't heard any other fullrange units sounding so natural. And like most 9710 owners, they swear by them.
Hello qwad,

Taiwanese drivers are cheap but not so good because they don't have the dynamic of old drivers or drivers like Fostex, Audio Nirvana, Moth Audio, Ciare (drivers not very expensive).
I love fullrange drivers and I have some. I prefer Fostex but I have try some old German drivers like Feho, DEW, Klangfilm,... etc . And they are very good and the sound is open, natural and alive.
I have a pair of FEHO 8" as good as models of todays fullrange manufacturers.
I have tested some Taiwanese drivers like Tang Band, they don't have the dynamic of old fullrange or todays fullrange like Fostex.
When you use a single ended of 211, 2A3 for exemple, the FE206E is a real natural cheap fullrange and philips, Feho, DEW could give you the same natural sound of a fullrange for less money.

Of course on Ebay, some prices become crazy. The price for a pair of Philips AD4200M in perfect condition must be 100 euros and not more, some Philips, Feho, DEW, Saba, Klangfilm 8" pair price must be between 30 and 75 euros and not more. When I see a Klangfilm 8" sell for the price of a FE208EZ I think it's stupid.
It's real that on ebay there is a lot of absurdity, like people who pay more for a second hand driver than the price for a new.
But even if people are often insane, we can find sometimes good fullranges for good prices

The problem with todays fullranges except some special manufacturers like Fostex, Audio Nirvana, Lowther,... is that they don't have enough efficiency and they are like all new drivers, flat and without life. A perfect flat curve for a driver give a driver without life.

Best Regards


PS: excuse me for my english ;)
I agree, prices are really increasing on ebay,

Now, I saw 9710M pairs leaving for 300$ and AD5200M for 400$, and I think this is far too high
(two years ago a 9710M pair was 150$ max)
This is incredible for 40 years old drivers...

Coral flat and beta prices are also really high, higher than new fostex ...


Regards to all


Now trying JBL Le8t bought 70 euros the pair with passive radiators just the surrounds in bad shape ...


2006-11-10 8:21 pm
pt2 planar tweeter

hey all... i was reading into these posts about the dayton pt2 planar tweeter... i am currently building a big speaker that consists of 2 12" paper pioneer woofers and 2 pt2s. the crossover is 3rd order for both the woofers and the tweeters.
what i am trying to conquer here is to fix the total response of the tweeter, xover point is at 2k. bombardon73 has posted something to do with this... any suggestions anyone?