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Phil Allison[_3_] Phil Allison[_3_] is offline
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Default Speaker Matching transformers.


"John Byrns"
"Phil Allison"
"Lord Valve"

http://taweber.powweb.com/store/zmatch.htm



** Hmmm: from what I can find using Google, it's an E-core, multi-tapped
auto tranny in a box.

Ought to work OK with valve / tube guitar amps - but maybe not so well
with bass amps.

And a definite NO NO with solid state amps, cos the core will saturate at
low frequencies and overload the output transistors, something fierce.



I have a 50 Watt solid state amplifier that is rated at 75 Watts into 2.4
Ohms.


** That's a bit of an oddball ?


You seem to be saying that I can't use a "multi-tapped auto tranny" to
deliver
75 Watts, how can I match an 8 Ohm speaker to 2.4 Ohms?



** You better not use that Weber unit unless your 75W amp has VERY good
overload and short circuit protection - ie VI limiting.

An auto tranny is not out of the question, but it would be wise to add a 50W
rated series resistor of about 3 ohms on the 2 ohm input and bypass that
with a pair of 1000uF, 50V electros wired back to back. Ideally, the core
ought to be toroidal too - for way less losses and better bandwidth.

The 8 ohms tapping needs to be rated at 50Vrms at 60Hz ( so 25Vrms at 30Hz)
for true hi-hi.

A simple centre tap should be close enough 2.4 ohms.


..... Phil