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Old 7th October 2010, 10:23 PM   #3551
udailey is offline udailey  United States
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Stuart,
I think he has 100uf BiPolar Nichicons and a .1uf Russion K73-16 across each.
Uriah
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Old 10th October 2010, 11:28 AM   #3552
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Originally Posted by udailey View Post
Stuart,
I think he has 100uf BiPolar Nichicons and a .1uf Russion K73-16 across each.
Uriah
Uriah

You mean bypass with 100uF+0.1uF = 100.1uF or just 0.1uF each leg of the LED...???

How far this improves to the LDR in your opinion?

What actually we try to do here...is it more current to the LED or just to stabilized it???
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Old 10th October 2010, 02:01 PM   #3553
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I'd like more clarification on this too... I think Uriah means 100u bypassed by .1u (like in 4th picture in post 3543). But, not sure.
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Old 10th October 2010, 02:13 PM   #3554
udailey is offline udailey  United States
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Gaba and Ray,
I have not yet tried the Russian caps so how much this improves over other .1uf caps I dont know. However I put 100uf and .47uf on each of mine and yes there is an audible difference. Look, the Lightspeed is incredible as is. All these modifications/changes can help but each will be small. The best change is a super quiet power supply. For the low low price of a 10uf up to 100uf cap on each LDR and a little film to bypass that its worth trying and I think you will find a slightly smoother character.
Uriah
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Old 10th October 2010, 02:58 PM   #3555
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Originally Posted by udailey View Post
Gaba and Ray,
I have not yet tried the Russian caps so how much this improves over other .1uf caps I dont know. However I put 100uf and .47uf on each of mine and yes there is an audible difference. Look, the Lightspeed is incredible as is. All these modifications/changes can help but each will be small. The best change is a super quiet power supply. For the low low price of a 10uf up to 100uf cap on each LDR and a little film to bypass that its worth trying and I think you will find a slightly smoother character.
Uriah
Yes. I agreed LSA is excellent as it is. Tested and proven.

Looks like the cap mod would be a weekend project....

Regarding you suggestion for quiet PSU for the LDR, I'm a bit confuse because I've been using your LDR for a quite a while since I got it from the first batch for matched pairs (100K). As I recall from the earliest pages of the LSA thread you've mention that quiet PSU is not necessary since the signal is 'flowing' along the resistor only but now why needed...?
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Old 10th October 2010, 03:10 PM   #3556
udailey is offline udailey  United States
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Gaba,
I didnt know what I was talking about then. I thought I did but I had no idea that there could actually be improvement by changing the supply. I thought we were ONLY lighting an LED, which... yes that is what we are doing but there is more to it than that. If the supply has 'dirty' electricity then the diode (LED) somehow transfers some of that to the resistor. I dont know if they are capacitively coupled because they are so close together or what, but if the supply is a switcher, for example, it might sound wonderful but when you put a better linear supply on it THEN you can tell the difference.
Uriah
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Old 10th October 2010, 03:19 PM   #3557
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Originally Posted by udailey View Post
Gaba,
I didnt know what I was talking about then. I thought I did but I had no idea that there could actually be improvement by changing the supply. I thought we were ONLY lighting an LED, which... yes that is what we are doing but there is more to it than that. If the supply has 'dirty' electricity then the diode (LED) somehow transfers some of that to the resistor. I dont know if they are capacitively coupled because they are so close together or what, but if the supply is a switcher, for example, it might sound wonderful but when you put a better linear supply on it THEN you can tell the difference.
Uriah
So bottom line LSA need a good PSU....

Looks like some mojo works when you don't need it sometimes...
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Old 10th October 2010, 03:49 PM   #3558
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[QUOTE=udailey;2328162]Gaba,
I didnt know what I was talking about then. I thought I did but I had no idea that there could actually be improvement by changing the supply.

Love this honesty !!
How very refreshing.

My kit hasn't arrived yet so I'm saving up my questions.
Great to know there are upgrades and tweaks once it's all up and running.

Andrew
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Old 10th October 2010, 05:53 PM   #3559
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I agree with Uriah. I've used an Andrew Weekes Super Reg (ALWSR) with my LSA clone (MkII circuit) and it sounds great. My theory is that a ripply supply will light the LED less perfectly, which is then replicated across the resistive element.

Then again, I usually don't have a clue what I'm talking about WRT electronics!!

Try a decent supply, though. Can't do any harm, can it?
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Old 10th October 2010, 05:59 PM   #3560
udailey is offline udailey  United States
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Originally Posted by jonclancy View Post
Then again, I usually don't have a clue what I'm talking about WRT electronics!!
Lies! Dont let this guy try to convince you he is ignorant Probably one of the nicest guys in DIYaudio and pretty smart to.
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