Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Leevi on October 24, 2016, 09:05:39 am

Title: Fender Twinolux EC
Post by: Leevi on October 24, 2016, 09:05:39 am

The Twinolux EC has an output power control which can be used to drop power.


Does anyone know how this function has been implemented?
Is it a passive attenuator only, voltage regulator or something else?


http://intl.fender.com/en-FI/series/artist-signature/ec-twinolux-230v-eur/ (http://intl.fender.com/en-FI/series/artist-signature/ec-twinolux-230v-eur/)


/Leevi

Title: Re: Fender Twinolux EC
Post by: SILVERGUN on October 24, 2016, 07:24:55 pm

Switchable power attenuator with the ability to cut off one speaker for reduced volume.

From a pdf I found published by Mercury Magnetics by Googling "twinolux output power control"
Cant post link cause Im on my phone and its way smarter than me

Title: Re: Fender Twinolux EC
Post by: PRR on October 24, 2016, 08:10:31 pm

> a pdf I found published by Mercury Magnetics

http://www.mercurymagnetics.com/pages/news/misc/EC-Series-amps.pdf (http://www.mercurymagnetics.com/pages/news/misc/EC-Series-amps.pdf)

But this says the same thing as the Fender sales-sheet you can find everywhere. No tech details.

Title: Re: Fender Twinolux EC
Post by: SILVERGUN on October 24, 2016, 09:22:33 pm

Yeah, Im ass-uming a lot, but it does seem pretty obvious...
Take away a speaker and put a resistor in itz place and you'll be seriously db deprived in no time.
Add a third positon and youve got a marketing masterpiece
VVR in this amp would be like variable valve timing in a snow blower

Title: Re: Fender Twinolux EC
Post by: Leevi on October 25, 2016, 01:43:35 am

Thanks for your replies. If I interpret this correctly it seems to be a passive way supported by the
Mercury Magnetics OT?
/Leevi

Title: Re: Fender Twinolux EC
Post by: VMS on October 25, 2016, 01:44:48 am

It could be much simpler.

I'm guessing it's the same that is on the EC vibrochamp with added position to switch the other speaker off.


vibrochamp schematic can be found on this thread:


http://el34world.com/Forum/index.php?topic=15254.0 (http://el34world.com/Forum/index.php?topic=15254.0)

Title: Re: Fender Twinolux EC
Post by: PRR on October 25, 2016, 10:40:25 am

> guessing it's the same that is on the EC vibrochamp

Yeah, that seems reasonable. Same brand and series, nothing complicated or costly.

But doesn't Eric bless each one?

Title: Re: Fender Twinolux EC
Post by: shooter on October 25, 2016, 10:47:48 am

Quote

would be like variable valve timing in a snow blower

:l2:
how fortuitous, I'm booting the snow blower today, maybe i'll do some mods before the 1st big'n