Understanding stepped attenuator choices

dobbykins · 23633

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Offline mcandmar

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Reply #15 on: October 18, 2013, 09:50:30 AM
Make-before-break is a term i have seen looking at various options.

I am leaning towards the Goldpoint from a quality/tactility point of view even though they no longer offer a ladder style, series only.

I priced up dale resistors from Mouser to populate a Goldpoint and they are ~

M.McCandless


Offline Paul Birkeland

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Reply #16 on: October 18, 2013, 12:48:05 PM
1/4W resistors are totally overkill.  1/100W resistors would be more than sufficient, and they are much easier to install on the switches.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


4krow

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Reply #17 on: October 18, 2013, 05:03:23 PM
I have used Goldpoint and just have nothing but good to say about them. I do believe that there a few others out the that are quite good. Wish I could think of the brand that I saw a while back. It just blew me away. It was up there with GP.



Offline mcandmar

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Reply #18 on: November 01, 2013, 04:45:42 AM
After reading good reviews on various sites i cheeped out and went for the $42 ebay kit.  I also opted for the DIY version as i'm a sucker for punishment  ::)   I'm more curious to hand measure/match the resistors more than anything.

I have yet to assemble and fully test it but the quality seems alright, doesnt feel that flimsy and all the resistors look like the real deal vs the stock of Dales i have on hand.  Amazing really as i couldn't have bought the resistors alone for $42 shipped. Its also much smaller than i was expecting, it looks coke can size in the photos, but in reality if more like those little cans you find in mini-bars. We will see how positive i am after i've soldered 90 odd resistors to it...

http://www.ebay.com/itm/DIY-kit-Dale-23-Step-Attenuator-for-Volume-Control-100k-/280321499342?pt=US_Amplifier_Parts_Components&hash=item414476a0ce

M.McCandless


Offline mcandmar

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Reply #19 on: November 01, 2013, 09:48:13 PM
If anybody is interested i have attached a list of the supplied resistors plotting the input impedance and resistance curves. It aint the best but i'm working on smoothing things out by swapping out a few resistors.

I also pulled it apart to look at the mechanism and its just regular plated steel contacts, time will tell how well it lasts.  I also advise you buy the ready assembled version as it took forever to build and can be rather tedious. The instructions (which are a bit vague) can be found here http://kikitronic.blogspot.ie/search/label/Attenuator%20for%20volume%20control

/edit: Added in the resistor values / charts as used in the Goldpoint ladder attenuator kits.
« Last Edit: March 09, 2014, 04:19:13 PM by mcandmar »

M.McCandless


Offline dobbykins

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Reply #20 on: November 10, 2013, 10:47:23 AM
Hi mcandmar,

Sorry that I didn't notice this before today, but I just wanted to give a quick message.  I'm glad to hear you went with the (non-assembled version of) the same attenuator I went with.  A couple things stood out to me when I installed this.  First, the detail was noticeably improved.  And second, on closer listening, the channel balance is better throughout the volume range.  I'm sure, if you don't have it installed yet, you'll be very happy with it.  I would not be surprised if a nice (expensive) attenuator was compared, that this would show some deficiencies, but for the price, I think it's hard to beat.  Maybe one day I'll be able to do a no-holds-barred amp, but for now, I'm happy to be able to use mid-level upgrades to gauge the importance of each component in the design.

Also, as you say, I'd definitely suggest getting the assembled version.  It's just not worth my time to solder in 90 resistors to save $10 or so.

Best of luck!

Guy Hilburn


Offline mcandmar

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Reply #21 on: November 13, 2013, 04:42:54 AM
Here's a question for Doc.B, have you considered making a BeeQuiet stepped attenuator upgrade for the Crack/S.E.X. amp?

I'm looking at the upgrade kit for the BeePre (shown below) and wondering if it would fit, looks like it could easily be condensed width wise by an inch or two, then all that's needed is a small top plate to cover the original volume pot hole and make it pretty.

Just a thought..

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.bottlehead.com%2Fsc_images%2Fproducts%2F464_large_image.jpg&hash=d8dc488fbe5dd6893f1bcce0127c9e4431fa0b55)

M.McCandless


Offline kgoss

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Reply #22 on: November 13, 2013, 05:15:39 AM
You can get that attenuator by using the submissive in front of the amp with the amp's volume at 100% or by replacing the amp's volume pot with a resistor.

Ken Goss


Online Doc B.

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Reply #23 on: November 13, 2013, 07:11:50 AM
Ken gets the gold star here. The Submissive is a pretty neat all purpose attenuator that sounds better than an awful lot of other controls out there. You can use it in all sorts of situations where you need a better attenuator or where you don't have one and you need some attenuation. As an example we have been experimenting with an active stepup preamp for moving coil cartridges that ended up with more gain than we could use so PB put a Submissive between the step up and our Eros phono pre to keep the signal from clipping the Eros. 

Dan "Doc B." Schmalle
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Bottlehead Corp.


Offline mcandmar

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Reply #24 on: March 03, 2014, 07:44:10 AM
Quick question, is there any advantage or disadvantage to using a 75k attenuator vs the stock 100k?

M.McCandless


Offline Paul Birkeland

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Reply #25 on: March 03, 2014, 07:53:51 AM
Quick question, is there any advantage or disadvantage to using a 75k attenuator vs the stock 100k?

For the majority of situations, these will be roughly equivalent.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline mcandmar

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Reply #26 on: March 03, 2014, 08:05:44 AM
Thanks Paul, just wanted to check that before i changed it in case it messed with the the amps operation in any way.  My source will only be DAC's so i assume the load difference wont matter to them.

M.McCandless