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Old 27th March 2013, 10:28 PM   #191
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What's the extra resistor for again?
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Old 28th March 2013, 02:21 AM   #192
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You need a pair of resistors to set the input impedance and to make sure a voltage doesn't build up between the output caps of your source and input caps of your amp.
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Old 28th March 2013, 02:40 AM   #193
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Imo :-) Inappropriate caps, the Goofy tone circuit is semi intact. The tone pots are still there . Did you physically remove the op amps (or One(?) on that earlier version board?
If not, they/it are Still impacting the sounds.. while the Resistors are IMO pointless.
But Hey! it's your amp .
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Old 28th March 2013, 02:59 AM   #194
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I've been wondering why it isn't just some traces cut and jumper wires placed from point A to point B. Desoldering practice?
But in the end it is pretty cheap DIY fun for those so inclined.
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Old 28th March 2013, 12:34 PM   #195
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R34, R35, R36, R37, C30, C31, C20 and C21 have been removed so the tone/pot circuit is completely out of the game...
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Old 1st April 2013, 11:21 PM   #196
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Default power supply

Quote:
Originally Posted by sofaspud View Post
I'm building a dedicated linear regulated supply for mine, so I may just remove and jumper that location.
Have you built one for this project yet? Curious as to what you used for a transformer. -thanks
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Old 2nd April 2013, 12:43 AM   #197
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There was a change in plans.
I ended up taking the power supply I was using for a T-amp (an old Radio Shack #22-124; 2.5A/5A surge) and using that with the Lepai. Then I built a new supply for the T-amp.
If I needed to acquire something new for the power supply, I'd look for a 12VDC SMPS brick rated for 3 or 4 amps output, or a 12V 3A to 5A transformer for a linear supply.
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Old 4th April 2013, 03:07 PM   #198
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What is the role of the output caps (near the inductors) I see in the pictures?
Are they worth to be changed?
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Old 4th April 2013, 03:13 PM   #199
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Originally Posted by Fukinagashi View Post
What is the role of the output caps (near the inductors) I see in the pictures?
Are they worth to be changed?
AFAIK, they filter DC. But there is more going on than that, because the white paper specifies different cap values depending on impedance of speakers. See the white paper for details.

And yes, even if you just stick to the existing values, replacing with some polyprops is a great idea.
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Old 4th April 2013, 03:15 PM   #200
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Quote:
Originally Posted by cogitech View Post
AFAIK, they filter DC. But there is more going on than that, because the white paper specifies different cap values depending on impedance of speakers. See the white paper for details.

And yes, even if you just stick to the existing values, replacing with some polyprops is a great idea.
Is there a suggested value for a 6 ohm speaker?
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