An Inside Look at Our Stepped Attenuator

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Wolf Ear Audio

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An Inside Look at Our Stepped Attenuator
« on: 14 May 2016, 11:01 pm »
Here's the inside picture of our stepped attenuator we offer as an optional upgrade for all of our amplifiers.
These are 24-step, ladder-type attenuators. Ladder types are by far the best performing type of attenuators and are made with no audio compromises, unlike shunt and series type attenuators.
The downside is that they require twice as many resistors to build because each step is its own volume control circuit with only one resistor in series with the signal path.
Our attenuators are hand made in house with 92 Vishay/ Dale Military grade, ultra-low noise and a rugged, silver plated 24-step attenuator switch.



EDIT Feb 27, 2018:
We got a bit better at making our attenuators over time, so I included some pictures on how our new 24 step attenuator is made (this one comes stock with all amps)  8)




This is just a bare switch



This one has its first row of resistors soldered in. We clip the leads and then do the other side.



This is a completed attenuator, tested and working perfectly!  :wink:
« Last Edit: 27 Feb 2018, 11:24 pm by Wolf Ear Audio »

Audiophile58

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Re: An Inside Look at Our Stepped Attenuator
« Reply #1 on: 4 Jul 2017, 10:33 am »
Hello many professional builders like Shunt ladder type attenuator s.
Khozmo comes to mind ,and relay controlled 63 step, only the last 2 are in the signal path
And are Vishsy Naked-  many people say Shunt is better.in my  DHT- preamplifier  that is preferred.
Thank you,Paul.

Audiophile58

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Re: An Inside Look at Our Stepped Attenuator
« Reply #2 on: 4 Jul 2017, 10:38 am »
Takes look here All Shunt types are not bad ,actually Very good. If you build yours this hood and use Vishsy
Naked pair on outputs you are doing Very well.

http://www.khozmo.com/products_dale_shunt.html

Wolf Ear Audio

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Re: An Inside Look at Our Stepped Attenuator
« Reply #3 on: 10 Jul 2017, 07:30 pm »
Shunt types aren't too bad, I just don't like volume controls that present a varying input impedance depending on where the volume is set.
I'm not using Khozmo atm (though I hear the new ones are nice), but I ordered some Elma attenuators (the 47 position type) to use in a custom build i am making for a client :)
I am flexible, so any amps I make (custom or not) can be made with any of these kinds of parts (or any others) if a client desires.

earwig

Re: An Inside Look at Our Stepped Attenuator
« Reply #4 on: 19 Jul 2017, 12:35 pm »
Had grey hill ones like the bottom picture on an arc sp6a,

Mike B.

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Re: An Inside Look at Our Stepped Attenuator
« Reply #5 on: 19 Jul 2017, 02:08 pm »
I have purchased two of the top example of ebay in the past. Nice attenuator.

Wolf Ear Audio

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Re: An Inside Look at Our Stepped Attenuator
« Reply #6 on: 19 Jul 2017, 08:13 pm »
I have purchased two of the top example of ebay in the past. Nice attenuator.
Probably not mine though ;)
I designed the attenuation curve on these and build them myself with RN Vishay resistors. Most you can find on eBay are made in China/ Thailand with fake name brand resistors and uneven attenuation between steps.

Wolf Ear Audio

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Re: An Inside Look at Our Stepped Attenuator
« Reply #7 on: 19 Jul 2017, 08:17 pm »
Had grey hill ones like the bottom picture on an arc sp6a,
I actually changed the way I build those ones now to be a bit more compact so the resistors don't stick out so much anymore.
I'll upload a new pic sometime :)

earwig

Re: An Inside Look at Our Stepped Attenuator
« Reply #8 on: 20 Jul 2017, 01:04 pm »
Watch the tolerances ohms match up very tight on both sides or you might get an uneven balance if you do the series version. Holco resistors are a good sounding brand for that too.You like the Totem speakers?

Wolf Ear Audio

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Re: An Inside Look at Our Stepped Attenuator
« Reply #9 on: 20 Jul 2017, 03:35 pm »
Watch the tolerances ohms match up very tight on both sides or you might get an uneven balance if you do the series version. Holco resistors are a good sounding brand for that too.You like the Totem speakers?
Channel matching is very good on these. Much better than any potentiometer. All the resistors are 1% or better tolerance (most of the resistors are much better than this)
I've never tried Totem speakers, but I have heard good things about them :)

earwig

Re: An Inside Look at Our Stepped Attenuator
« Reply #10 on: 21 Jul 2017, 01:22 am »
I mentioned Holco due to a Micheal Percy catalogue that mentioned ,copper leads ,gold plated end caps and he found the tolerance as good as 0.25%.Is that an Electroswitch?Yes Im fixing and upgrading some caps in my Totem Forests right now.
« Last Edit: 25 Jul 2017, 10:56 am by earwig »

Wolf Ear Audio

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Re: An Inside Look at Our Stepped Attenuator
« Reply #11 on: 27 Feb 2018, 11:25 pm »
I updated the build for our standard attenuators and included new pictures for anyone interested  :)

Folsom

Re: An Inside Look at Our Stepped Attenuator
« Reply #12 on: 28 Feb 2018, 02:55 am »
The ones on eBay have bad sibilance, and so do some others... In fact I think it might be a problem with the actual mechanical device.

Mr. Wolf Ear, have you used a DACT from eBay?  You might prefer it over the ones you build. They are that good. Only downside is they aren't as robust with more steps.

Wolf Ear Audio

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Re: An Inside Look at Our Stepped Attenuator
« Reply #13 on: 28 Feb 2018, 06:37 pm »
The ones on eBay have bad sibilance, and so do some others... In fact I think it might be a problem with the actual mechanical device.

Mr. Wolf Ear, have you used a DACT from eBay?  You might prefer it over the ones you build. They are that good. Only downside is they aren't as robust with more steps.
I do not use the same parts as eBay. I know the switches you are speaking of since I have used them for quick prototypes before and they really are not great, but these switches I have been using are made better and have very solid contact on each step (there is a gigantic quality difference between the solid blue switches on eBay and the brown ones I use). I also don't use any Chinese resistors anywhere in this amp, not even in the attenuator.
On the other hand, DACT makes very good products, but even their potentiometers would increase the price of this amp. I chose to build these attenuators because they offer the best value for performance, much better than any potentiometer I have ever used, though not as good as some premium stepped attenuators such as those made by DACT and other premium parts manufacturers.
However, if anyone wanted to use a different part than those I use, that can always be arranged too  :thumb: