Bottlehead Forum
Bottlehead Kits => Crack => Topic started by: danosol on June 04, 2013, 01:45:19 PM
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Any recommendations as to whether it's better to get the SMD version of the Goldpoint attenuator or the blank and populate it yourself.
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Populated with Dales sounds best.
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Thanks Doc I remember you telling me that but i wanted to make sure. They are pretty high on their SMD resistors.
By the way 1/4 or 1/2 watt resistors?
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By the way 1/4 or 1/2 watt resistors?
1/16 or 1/8 watt are great, and easy to fit on the switch. The RN55D's are solid, as are the little red PRP's.
Populating the switch yourself is vastly more rewarding than just throwing in a replacement pot.
-PB
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Do they make the Dale's in 1/8 watt.
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There's an RN50 that's smaller, but they cost a lot more. A 1/4 watt Dale is a good size for those switches, just bend a lead over on one side.
-PB
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I may be mistaken here but I believe that there have been a few posts which relayed that some Bottleheads preferred the Sweetest Whispers over the Goldpoints with preinstalled SMD resistors. I believe the threads were related to the Foreplay pre. This doesnt translate necessarily as a comparison to the stock Alpha carbon pot in Crack ... although you never know. Always thought the Alphas sounded better than their price, assuming a good one and channel imbalance at lower levels not taken into account. Anyway, while I have no experience with the Goldpoints installed in Crack and I also lean toward preferring a continuous countrol rather than a stepped for a headphone amp, if I were to go with a Goldpoint I'd definitely take the advice in this thread and build my own with leaded resistors.
For what it's worth anyway.
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Just curious after listening a bit tonight I noticed that the bass on my Speedball equipped Crack tends to get a bit muddy at the 12:00 position on certain tracks. At 10:00 it sounds better. I'm wondering if that has to do with the stock pot.
Also when calling GP the guy there said that even an Chinese stepped attenuator would sound better than what I have currently. If that is the case which one should I get?
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Just curious after listening a bit tonight I noticed that the bass on my Speedball equipped Crack tends to get a bit muddy at the 12:00 position on certain tracks. At 10:00 it sounds better. I'm wondering if that has to do with the stock pot.
Also when calling GP the guy there said that even an Chinese stepped attenuator would sound better than what I have currently. If that is the case which one should I get?
The bass muddiness may have to do with power output and your particular headphones, what impedance are they?
Yes, there are Chinese stepped attenuators that sound rather good. I have a couple rolling around in some of my gear, and after four or five years, certain parts have rusted and oxidized to an unpleasant level. Arn's switches (Goldpoint) don't do this.
-PB
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It's the HD 600 300 Ohms I believe.
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The problem with the inexpensive Chinese attenuators is the quality of the switch. Many you will find seem to use the same white and blue plastic cased no-name switch. They also use all different types of resistors, some cheap, some well regarded so keep an eye on that aspect. I know they sell those switches for cheap so you can install your own resistors. But that particular switch sells for under $10 which tells much of the story. Of course there are probably several others that use a different switch. Regardless, there are still some that are supposed to sound pretty good but they arent going to hold up like a Goldpoint or other brand that uses a high quality switch. I have one that I bought based on reviews, was supposed to be good bang for the buck. I cannot recall the seller but I believe it may have been Valab. And I havent used it yet so cant comment on sonics. I decided not to install it in Crack because I wanted the finer control of a rotary volume pot. I will eventually install it in an amp I have. I know that some here dismiss the stock Alpha pot so I guess Im in the minority in saying that I never thought they sounded bad. They wont last forever, tend to get scratchy, arent the smoothest and they do tend to have the imbalance at the lower listening levels. For that reason, I replaced with an Alps "Blue" which I think are pretty good at the price ($14 at Mouser electronics) although some also dismiss the Alps. I've never heard the Alpha pot change the character of the sound at certian listening levels.
Do some internet searching for related terms concerning chinese stepped attenuators, you should come up with some hits. Or better yet, search ebay and then search for comments based on what you find from certian sellers. Valab and, I believe, 8audio, are a couple pretty popular chinese sellers. There are others. You can always pick up a cheap chinese stepped or two and just do some experimenting/listening. Maybe an Alps "blue" ($14 at Mouser) if you want to try a different rotary pot later on. If they dont suit you, you wont be out much, you'll have some spare parts and can go with a Goldpoint. Or just bite the bullet and go with the Goldpoint ;)
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I recently replaced my Alps Blue with the Goldpoint Mini-V (stock SMD resistors) recently, though it may or may not have been a better than the Alps/TKD pots or even a custom mini-v with dale resistors, I find the most obvious improvement was the blackness of the background ("clean sounding") and am very satisfied otherwise. Although, an Alps Blue pot is a definite upgrade over the stock Alpha pot for starters, the low level imbalance and sudden gain with the stock pot was unbearable after awhile.
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the low level imbalance and sudden gain with the stock pot was unbearable after awhile.
Nick I think that's what I'm noticing a bit, not so much the channel imbalance but the sudden gain. Gonna get a pot soon.
I saw on GP's site the resistors needed to populate the attenuator, but I was not able to find some of the values in Mouser's catalog.
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I gotta tell ya guys, it's not painless putting out the money for the GP switch, but it's worth it. They are also easy to work with. As I have mentioned before, sometimes you can get a good ceramic non-shorting switch at fleabay, but no promises. The Russian military ones seem to be the best if the size is right.
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Does the Crack chassis have to be modified to accommodate the GP.
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Does the Crack chassis have to be modified to accommodate the GP.
I would be interested to know if it will fit as well. It looks like the mounting hole for the GP is around 10mm and the mounting hole on the chassis is 8mm, can someone confirm this?
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It looks like there's enough room in the chassis. The hole in the Crack chassis is just shy of 9mm, and you can get a large round file to enlarge it slightly. Due to the anti-rotation slot attached to the hole, drill bits may want to snag if you use them.
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Thanks for the help PB! Will follow your advice on that
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I have One of the blue and white switch based pots with Dale resistors. And it works fine sounds good. I got it when it first came on the scene I don't know if the switch has changed over the years but I do crank it through it range a few times every now and again to keep the contacts clean...John
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Thanks for the insight and suggestion 2wo!
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I installed the goldpoint attenuator a week ago and I think it sounds fantastic. However, I am getting some popping sounds when I raise it up or down. I read that this is fairly common in stepped attenuators, but is there a way to get rid of this noise? Arn from Goldpoint said to try adding coupling caps, what kind do I need, and how do I install it?
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A Valab or a Khozmo attenuator won't pop. Goldpoint attenuators have been used for decades in our Foreplay preamp without popping (which has the same first gain stage tied to the attenuator that the Crack does). Perhaps just try a Valab instead?