Yes. I should have but thought people who ae able to build their own amp really understand science and engineering of making an amp. For others, amps are works of art and need to be appreciated using words like "musical", "smooth", "fluid", "open", "airy" and words like that. Those words do not help me select an amp or decide if I need to upgrade my amp.You should start your own thread with these questions. This thread is about Apex amps which are DIY. You will get far more folks looking at your questions.
Most of those Audiophiles give me advise like "buy the best amp you can afford". That assumes that if I can afford $20,000 I should buy one. What I wanted to understand is what additional sound quality I get for the additional money. Isn't that a fair question.
Yes. I should have but thought people who ae able to build their own amp really understand science and engineering of making an amp. For others, amps are works of art and need to be appreciated using words like "musical", "smooth", "fluid", "open", "airy" and words like that. Those words do not help me select an amp or decide if I need to upgrade my amp.
Most of those Audiophiles give me advise like "buy the best amp you can afford". That assumes that if I can afford $20,000 I should buy one. What I wanted to understand is what additional sound quality I get for the additional money. Isn't that a fair question.
The best excuse in the whole world is still and excuse. Most, if not all of the folks in this thread could care less about the amps you asked about. We are builders, not buyers. Suit yourself.

Yes. I should have but thought people who ae able to build their own amp really understand science and engineering of making an amp. For others, amps are works of art and need to be appreciated using words like "musical", "smooth", "fluid", "open", "airy" and words like that. Those words do not help me select an amp or decide if I need to upgrade my amp.
Most of those Audiophiles give me advise like "buy the best amp you can afford". That assumes that if I can afford $20,000 I should buy one. What I wanted to understand is what additional sound quality I get for the additional money. Isn't that a fair question.
Only DIY amp give you additional sound quality for the additional money rest is advertising.
Regards
Good news,my A23 amplifier it's playing nice , but it's to late to give volume on input .....😎 Until tomorrow, some pictures . Rail voltage only +/-36V for testing . Offset voltage after 45 min, +27 mV
Regards ,Alex
Nice work, offset must be about +/-1mV, do some voltage measurements and replace 3k3/2W with 1k/2W with +/36V rails,
Regards
🙂 thanks for answer i'l try to change 3k3 /2w resistors . Rail voltage for IC it's only 8V instead 15V . Link to movie https://www.youtube.com/watch?feature=player_detailpage&v=4I6khZgsI4o
Regards,Alex
Regards,Alex
🙂 thanks for answer i'l try to change 3k3 /2w resistors . Rail voltage for IC it's only 8V instead 15V . Link to movie https://www.youtube.com/watch?feature=player_detailpage&v=4I6khZgsI4o
Regards,Alex
Nice work, but you must have +/-15V rail voltage for IC, this voltage determinate current thru diamond buffer and VAS.
Regards
Zenner resistors changed to 1K1/2W ,also IC from LME49713 to TL071 and resistor from bias pot from 680 ohm to 750 ohm .With this values , offset it's only 0.5 mV , current through OT set to 65 mA /device and magic sound can be hear from my speaker . For testing purpose rail voltage +/-36V . I think I will build also A33 amplifier . 😀
Regards,Alex
Regards,Alex
Zenner resistors changed to 1K1/2W ,also IC from LME49713 to TL071 and resistor from bias pot from 680 ohm to 750 ohm .With this values , offset it's only 0.5 mV , current through OT set to 65 mA /device and magic sound can be hear from my speaker . For testing purpose rail voltage +/-36V . I think I will build also A33 amplifier . 😀
Regards,Alex
APEX vs Goldmund?
Awesome!
Did you build them in pairs so you can listen in stereo?
Only a few. I built ready AX14 (my favorite), quasi complementary for beginners, AX11, LM3886, AX6. SR100 I have two channels...
It's an exciting hobby 🙂
perfect
made in Germany
Just for fun - update of the actual gallery for 2014 (AX20 built in 2013) 🙂
regards Olaf
made in Germany
i mostly use old and cheap cassete-deck inclosures,that way i get almost the whole box - i only need to do front and rear side wich is a lot easier than to do it all:
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"best buy" are the one made in mid 80´s and early 90´s,cheap but still well made,strong and heavy enough to carry larg transformer and heatsinks... that is how i made APEX A23 to...
they will not win AMP-Olympics,but they look good enough for me - and the best of all i know what is inside 🙂
they will not win AMP-Olympics,but they look good enough for me - and the best of all i know what is inside 🙂
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APEX vs Goldmund?
I have to build, the second channel ,first .....😉
"best buy" are the one made in mid 80´s and early 90´s,cheap but still well made,strong and heavy enough to carry larg transformer and heatsinks... that is how i made APEX A23 to...
they will not win AMP-Olympics,but they look good enough for me - and the best of all i know what is inside 🙂
This looks very good. At least you have housing, not as I do 🙂.
But a few I've also built. I use plywood and perforated sheet of aluminum. If I have, then, a right front panel made of aluminum or last trial of Plexiglas.
Because I need a long time for that, I have a lot more amps than housing 😀
regards Olaf
edit: VU should mounted behind the Plexi. It is Apex-VU from 1000W-Thread.
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it will be all right when you do a few enclosures "in a roll",you wil see that you´re doing them fine and than you will get even maybe to like that part od DIY - that is how it was with me. i believe that you will find your way/path to do it easy,fast enough and to be satified how it looks.
i like the way you did AX14,specially top of the inclosure - perforated Al all arround means a lot of air to cool things inside 🙂
the thing with VU meter behind darkened plexy also promises,it is almost erotical - in it´s own way : you can see it,but not quite all of it... 🙂
i can´t see anything but a lot of pleasure for you in a near next future... see it and take it as a fun - and than you will have a fun! 🙂
i like the way you did AX14,specially top of the inclosure - perforated Al all arround means a lot of air to cool things inside 🙂
the thing with VU meter behind darkened plexy also promises,it is almost erotical - in it´s own way : you can see it,but not quite all of it... 🙂
i can´t see anything but a lot of pleasure for you in a near next future... see it and take it as a fun - and than you will have a fun! 🙂
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Christmas is coming soon, then we will see, it is a bit more time for diy-audio 🙂
Good Night
Olaf
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