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Philips 9014 and 9015

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Posted on November 2, 2020 at 20:16:31
ChasLieb
Audiophile

Posts: 284
Joined: April 7, 2002
 The 9014 was an OTL amp but apparently only output into Philips own 800 ohm speakers. The 9015 added an output transformer to drop from 800 to 8 ohms. Does anyone have experience with these amps or modifying these designs to run with more modern speakers? Maybe inserting an autoformer on the older 9014 to do away with the OT but boosting the reflected impedence to the amp. For 10w these little amps may work well with high efficiency speakers.

 

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RE: Philips 9014 and 9015, posted on November 3, 2020 at 11:14:40
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 The problem is you need an 800 ohm speaker, which only Phillips made for their products.

So if you're going to use a real-world speaker you'll need an output transformer. Or a different power tube.

 

RE: Philips 9014 and 9015, posted on November 3, 2020 at 16:29:37
ChasLieb
Audiophile

Posts: 284
Joined: April 7, 2002
 Thanks for checking in Ralph. The later 9015 does have an output transformer so in addition to the 800 ohm output it can output at 8ohms. I don't know anyone who has heard these amps and the schematics, shown here https://philipsag9015home.files.wordpress.com/2019/07/ag9015_sch.png are interesting and suggest room for part upgrades. Given the low output power of about 10w they are only of use with high efficiency speakers. If I can get one cheap I may try it out with a set of Gallo Strada IIs and a subwoofer. Maybe even worthwhile to get a set of vintage philips drivers to play with. Hoping someone who has seen these in person can chime in.

 

RE: Philips 9014 and 9015, posted on January 31, 2021 at 11:42:25
Altainefficienza
Audiophile

Posts: 1
Joined: January 31, 2021
 Hello, I'm new in this Forum and am checking the interesting threads...
My two cents on this one.
I own some AG-901x Philips amps. I am still trying to make the 9014 work (some issues with the switches), but have a pair of working 9015 and an 9018. They are very good amps both connected with the 800 Ohm speakers (most tipically the 9710 in the AM version), and when used with conventional ones (a switch can select between 8 or 16 Ohms). Apart from its limited 15 Watts output, only issue is the non svitchable loudness feature, but it can easily be solved desoldering this feature from the volume pot.
They are complex but solidly built, and perfectly on a par with modern good amps soundwise.
They have a great hystoric value, being the archetype of most modern solid state amps with their SEPP output circuit.
Best regards,
Piero

 

RE: Philips 9014 and 9015, posted on January 31, 2021 at 12:13:20
rivervalley817
 cheers ...

 

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