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Old 12th April 2013, 07:07 PM   #121
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Well 3v is ~10% . I need to recheck it in different times of the day to see whether this is the cause for the decrease in voltage . Anyway , I am using 6l6gc tubes and the measuremens were taken without the tubes .
Regarding the max volume , Is it possible that the POT is not covering the full scale of the available volume ?
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Old 12th April 2013, 07:38 PM   #122
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Quote:
Originally Posted by sagi4422 View Post
Is it possible that the POT is not covering the full scale of the available volume ?
Not really, here's why:

The pot is a passive device, and it can only subtract (attenuate) the signal. When the pot is turned fully clockwise, it is essentially a short circuit, ie no attenuation/subtraction.

If you measure the pot wiper to the end terminals with the wiper at full travel clockwise, you will get zero ohms (or very close to it) from the wiper to one end, and the value of the pot in ohms from the wiper to the other end. Turn the pot fully CCW, and measure again; you will reverse the above. The pot needs to be out of the circuit to measure the various R's.

So, in summary, with the pot fully clockwise it's like no pot at all, ie zero attenuation. That's as loud as your amp is going to get for a given input signal. Keep in mind that different sources have different output levels as well, ie your ipod may play louder than your CD player, etc.
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Old 12th April 2013, 07:49 PM   #123
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Thanks . I will check this issue.
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Old 12th April 2013, 08:25 PM   #124
PDL is offline PDL  United States
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Quote:
Originally Posted by sagi4422 View Post
Well 3v is ~10% . I need to recheck it in different times of the day to see whether this is the cause for the decrease in voltage .
3v is .6% of 500v, I wouldn't worry to much about it.
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Old 12th April 2013, 08:32 PM   #125
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The change in voltage was not seen in the PS secondaries . It was seen in a place where formerly was 34v and now 31
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Old 15th April 2013, 05:45 PM   #126
rknize is offline rknize  United States
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You were measuring the heater filament's DC offset to ground. It's not all that important. Did you see my previous post? I don't think that you measured the correct pins.
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Old 19th April 2013, 05:26 AM   #127
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Originally Posted by rknize View Post
You were measuring the heater filament's DC offset to ground. It's not all that important. Did you see my previous post? I don't think that you measured the correct pins.
I double check it and compared it to the schematics I got. It seems that I was measuring the right pins.
Anyway, the voltage values are OK.
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Old 19th April 2013, 05:30 AM   #128
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Almost finished, with the chassis.
Left are some painting issues and templates for the switches.
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Old 29th April 2013, 09:03 PM   #129
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Hi.
Another interesting question, can I use the Simple SE as preamp (in a certain configuration)?
I just got a nice vintage Sansui AU717 and I dont know how to handle more than one amplifier
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Old 30th April 2013, 12:48 AM   #130
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Default Can the Sansui be run as a power amp?

Quote:
Originally Posted by sagi4422 View Post
Hi.
Another interesting question, can I use the Simple SE as preamp (in a certain configuration)?
I just got a nice vintage Sansui AU717 and I dont know how to handle more than one amplifier
Bi-amp with the SSE driving the tweeters (with proper protection) and use the Sansui for the woofers. You can also change the value of the coupling caps in the SSE for a higher cutoff freq when just powering the higher freq drivers. This makes life easier on the amp (and allows additional "apparent" power) since it does not have to pass the higher powered low freq signals.

Taking it one step further, you can throw an active eq between the source and the amps for easy x-over tailoring.
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