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Old 1st April 2012, 02:12 PM   #381
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Default whats the status?

did you make another amp? and make it stereo.and how's the new dawn 1diffqc amp?

regards,
joel
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Old 1st April 2012, 04:14 PM   #382
PauloPT is online now PauloPT  Portugal
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Quote:
For an EF output stage expect 20 to 25mVre through 0r22re.
That comes out at ~100mA of bias through each pair.
Yes, the big improvement was moving from 13 to 26mV. There's not much difference going higher, at least that I can perceive.

Quote:
I just stayed at 46mv. across two resistor emitter.theres something I read in books about gm doubling.when you try to bias a class b output as same as class a.besides my heatsink could not handle more heat.height is 3.75" which is very small.
Perhaps it's better to go with only 26 mV for safety. I have big heatsinks but as I said above there's little difference going higher.

Quote:
did you make another amp? and make it stereo.and how's the new dawn 1diffqc amp?
Yes, I did. The 1DIFFQC sound similar to the SYMEF but there are some differences. I don't know how much the TIP outputs are contributing for a different sound or if it's just because topology is different, but the DIFF sounds a little more mellow and with a little less treble. They are both very good performers and it's hard for me to pick one over the other.

Quote:
p.s.
next time be aware of the polarity and stick to safety region.
The poor guy saw 35V reversed at his terminals! It was hot as hell!

Guys, I need your help in this: I'm going in circles soldering and desoldering capacitors, deciding wich to use. The truth is that I don't fully like any electrolytic I've tried. The industrial types like lelon and panasonic seem more fluid but there's something wrong tonaly with them. The Silmic's, althout very smooth, kill the energy of the sound. The Nichicons KZ are almost good but the top end is a bit harsh or confused - I don't know what words to use to better explain this. So I ask you guys: what is your advice? And is there any bypass that works as a solution (electrolytic + film)? What are your feelings about electrolytic caps - how do you choose wich ones to use? You built the SYMEF and perhaps the DIFF with wich types of caps?

Thanks.
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Paulo.
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Old 1st April 2012, 04:52 PM   #383
PauloPT is online now PauloPT  Portugal
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I have 4 black gates 47uF 16V. Could I use them in place of the 100uF in the current sources across zeners?
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Paulo.
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Old 2nd April 2012, 08:58 AM   #384
AndrewT is offline AndrewT  Scotland
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Quote:
I just stayed at 46mv. across two resistor emitter.
Quote:
Originally Posted by PauloPT View Post
Perhaps it's better to go with only 26 mV for safety.
46mV across two emitter resistors is the same as 23mV across one emitter resistor and gives ~100mA of bias.
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regards Andrew T.
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Old 4th April 2012, 02:29 AM   #385
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Default ....packages

Packages should start landing at your door any time soon, mrsavage check your mail, they told me you would get it today
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Old 4th April 2012, 02:31 AM   #386
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....I don't know how fast your customs is Paulo, maybe you get it between now and 5th
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Old 4th April 2012, 02:39 AM   #387
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Default .....more builders needed

.......your opinion counts, This amplifier is based on a model that predicts you will like it , a lot. But don't take my word for it, try it and let us know your opinion. You could always checkout the good job done by Drow and Paulo by reading the whole thread or visiting Gallery

Last edited by OnAudio; 4th April 2012 at 02:42 AM. Reason: typo
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Old 4th April 2012, 02:32 PM   #388
PauloPT is online now PauloPT  Portugal
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Hi Harrison,

Quote:
....I don't know how fast your customs is Paulo, maybe you get it between now and 5th
It would be a birthday gift

Portuguese customs are slow, it takes about 2 months for things to get cleared. But not every package is picked for inspection and tax - I'm hoping boards isn't because should be a small package looking like a letter or documents and not be inspected.
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Old 4th April 2012, 03:04 PM   #389
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Happy birthday, you share one with my cousin within 3 days
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Old 4th April 2012, 03:10 PM   #390
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now I sing for you.... use text to speech

Happy birthday to you, happy birthday to you, happy birthday dear Paulo, happy birthday to you, how old are you now, how old are you now, happy birthday dear Paulo happy birthday to you, I went to the zoo, I went to the zoo and I saw a ..... and I thought.....
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