Anyone built an attenuator?

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Miza
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Anyone built an attenuator?

Post by Miza »

Been thinking about buying or building an attenuator for my Fender Pro Jr, just to match it better to my Vox AC4HW for home use when playing in stereo. Since I've built a few pedals, I figure I'll try and save some coin and go DIY.

Has anyone built one before? Any tips or warnings?

Some of the L-Pad designs look pretty simple. Jansen has this on their website, but it's only rated for 10 watts:
https://jansen.nz/product/alps-8-ohm-l- ... 22381.htmx

Then there's this part, which is 15 watts, but is it better to overcompensate rather than match the wattage?
https://www.parts-express.com/L-Pad-15W ... hm-260-248
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Re: Anyone built an attenuator?

Post by sizzlingbadger »

You want a 30W attenuator to be safe, you may as well build a 50W attenuator and then it will be more useful in the future.

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Re: Anyone built an attenuator?

Post by calling card »

I bought a couple of those Lpads from Parts Express once, 50w - 75w power handling? (memory is poor). I went down the THD Hotplate path instead. Nuisance though as you need a lot of THD's to match different amp types/impedance.

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Re: Anyone built an attenuator?

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Re: Anyone built an attenuator?

Post by Miza »

Cheers for the link.
Looks easy enough, the hard part will just be finding all the parts (that is to say, avoiding $$ shipping fees).
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Re: Anyone built an attenuator?

Post by TmcB »

I have built a couple of Brakelite's – the parts are annoying to source, the testing is stressful but it's good

I actually have a bunch of parts to make one still if you'd like me to dig them out
*UNIQUE* wrote:Tony, your taste is, as always, very refined. Or as HG would say, "bloody awful".

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Re: Anyone built an attenuator?

Post by TmcB »

43067686-EB94-4D55-86F4-E30A6B81E7D9.jpeg
43067686-EB94-4D55-86F4-E30A6B81E7D9.jpeg (671.13 KiB) Viewed 361 times
Innards of a brakelite
*UNIQUE* wrote:Tony, your taste is, as always, very refined. Or as HG would say, "bloody awful".

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Re: Anyone built an attenuator?

Post by wavesofffear »

I haven't, but if I did, I would probably build one like so: https://www.marshallforum.com/threads/s ... ing.98285/

"JohnH" is in Aus, so he has some good advice on which parts can be sourced from Jaycar in there too!

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Re: Anyone built an attenuator?

Post by Molly »

I once looked inside my Dr Z attenuator and there seemed nothing to it.

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Re: Anyone built an attenuator?

Post by StrummersOfThunder »

L pads sound poos

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Re: Anyone built an attenuator?

Post by Miza »

TmcB wrote: Mon Aug 01, 2022 4:49 pm I have built a couple of Brakelite's – the parts are annoying to source, the testing is stressful but it's good

I actually have a bunch of parts to make one still if you'd like me to dig them out
Yeah cool, let me know what you got!

I need to place an order with Tayda sometime soon, so I'll be able to get an enclosure and jacks easy enough.
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Re: Anyone built an attenuator?

Post by calling card »

TmcB wrote: Mon Aug 01, 2022 4:49 pm I have built a couple of Brakelite's – the parts are annoying to source, the testing is stressful but it's good

I actually have a bunch of parts to make one still if you'd like me to dig them out
Is the impedance variable on the Brakelite?

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Re: Anyone built an attenuator?

Post by TmcB »

calling card wrote: Tue Aug 02, 2022 7:24 am
TmcB wrote: Mon Aug 01, 2022 4:49 pm I have built a couple of Brakelite's – the parts are annoying to source, the testing is stressful but it's good

I actually have a bunch of parts to make one still if you'd like me to dig them out
Is the impedance variable on the Brakelite?
Sort of – it's variable in the sense that its method of working varies the impedance to achieve the attenuation. But yes, it's not like the Hotplates where you have a fixed impedance
*UNIQUE* wrote:Tony, your taste is, as always, very refined. Or as HG would say, "bloody awful".

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Re: Anyone built an attenuator?

Post by griff »

Molly wrote: Mon Aug 01, 2022 5:54 pm I once looked inside my Dr Z attenuator and there seemed nothing to it.
Open up ya power station, different story.

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Re: Anyone built an attenuator?

Post by wavesofffear »

TmcB wrote: Tue Aug 02, 2022 9:02 am
calling card wrote: Tue Aug 02, 2022 7:24 am
TmcB wrote: Mon Aug 01, 2022 4:49 pm I have built a couple of Brakelite's – the parts are annoying to source, the testing is stressful but it's good

I actually have a bunch of parts to make one still if you'd like me to dig them out
Is the impedance variable on the Brakelite?
Sort of – it's variable in the sense that its method of working varies the impedance to achieve the attenuation. But yes, it's not like the Hotplates where you have a fixed impedance
The Brake-Lite is a resistive load (as opposed to a reactive load).

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