Ok friends, again there.
Treble rolloff doesn't appear on the left channel.
Last time I measured only right channel.
On the right channel -3dB point shifted to 22kHz.
I have an idea on what's happening... Let me make some order here and I guess it'll be fine.
Now it's a mess!
Treble rolloff doesn't appear on the left channel.
Last time I measured only right channel.
On the right channel -3dB point shifted to 22kHz.
I have an idea on what's happening... Let me make some order here and I guess it'll be fine.
Now it's a mess!
Attachments
Well, that escalated quickly 😀 (somehow my notifications did not work..)
Thanks for all the input, I will read through it and look which could help me for my task
Sure, but I thought its called DIYaudio 😛
Thanks for all the input, I will read through it and look which could help me for my task
Sure, but I thought its called DIYaudio 😛
I reserve my DIY efforts for projects that I can't find commercially or that save me a significant amount of money. It seems to me the Asgard II, which I own, would satisfy both criteria.
I admire that you want to implement your own design, but it's not where I would spend my time or money. OTOH, maybe you can do better.
Audiobomber, what you say is an absolute valid approach, The idea is not spending money on DIY but finding out what different designers characteristic sound is and by tinkering create the sound signature that you really enjoy. Then compare this with your commercial Asgard and then establish which one you like more, not looks but sound. Now you gained a bit of experience in sound signature and you may be able to tweak the Asgard to sound more the way you want. Every designer adds his own flavour of sound signature, else every amplifier built to rigid specs will sound the same.
My headphones/line preamp with no GNFB and nice harmonic profile is here https://www.diyaudio.com/community/threads/gainwire-line-phone-non-gnfb-preamp.395695/#post-7546815
and if you like to put some "makeup" lok here https://www.diyaudio.com/community/...ne-non-gnfb-preamp.395695/page-2#post-7591547.
Gerbers are here https://www.diyaudio.com/community/...ne-non-gnfb-preamp.395695/page-3#post-7733838
Damir
and if you like to put some "makeup" lok here https://www.diyaudio.com/community/...ne-non-gnfb-preamp.395695/page-2#post-7591547.
Gerbers are here https://www.diyaudio.com/community/...ne-non-gnfb-preamp.395695/page-3#post-7733838
Damir
Thank you! And if I may add: with this approach I have the chance to add more features (DAC/Streamer..) in a single enclosure which I can design to my liking and dont havt to stack multiple "boxes" from different manufactuers on my desk.
Another important point is the joy of learning something new, since I want to improve my simulation skills a bit I probably will simulate a few of the suggested circuits in LTSpice and than decide which one to finally build. At the moment I am collection ideas, I still want to use the good weather in the summer and really dive into this project in autum/winter 🙂
Caveat: picture heavy, but thumbnails.
Friends, in the end i would call this little amp "the wire". It is a really really nice small amp, with tons of power. Incredible. My 20ohm planars are now singing.🤩
Target was using everything I had stocked (apart 2sa1387 or was it 1384?), and so be.
I used a case from a Chinese raspberry+DAC which lied abandoned, and very few components.
Apart from the usual pictures, let's have a look at the scope:
This is the beginning to the end result
Rolloff is gone. Perhaps it was the capacitance of all these cables in the wild configuration, I don't know. Something around 57khz has a small dip, but who cares?
Now, I'm no good at using fft in the scope, to get the second picture I had to give a 2Vrms signal in and pump at full volume. Now, I can't discern how it is, but at low volume setting (which is LOUD, believe me) harmonics disappear. I can't just use it. These two are with R load 56ohm
These three are for R16ohm load.
As said, big signal, big volume, no harmonics? What did I do wrong?
However, now my 20ohm planars sing, find them no more shy.
It's like you get what you have, with a poor quality recording, you will get poor quality amplified.
I am happy.
Let me thank @adason, @Nico Ras , @widea , and the great @AKSA for this small but great sounding "wire".
Who has questions, I'll be happy to respond.
Power resistors are 56 10W non inductive and 22 (or 20, don't remember) 5W non inductive.
Keep cabling short, and that's it! 😁
See ya 😎
Friends, in the end i would call this little amp "the wire". It is a really really nice small amp, with tons of power. Incredible. My 20ohm planars are now singing.🤩
Target was using everything I had stocked (apart 2sa1387 or was it 1384?), and so be.
I used a case from a Chinese raspberry+DAC which lied abandoned, and very few components.
Apart from the usual pictures, let's have a look at the scope:
This is the beginning to the end result
Rolloff is gone. Perhaps it was the capacitance of all these cables in the wild configuration, I don't know. Something around 57khz has a small dip, but who cares?
Now, I'm no good at using fft in the scope, to get the second picture I had to give a 2Vrms signal in and pump at full volume. Now, I can't discern how it is, but at low volume setting (which is LOUD, believe me) harmonics disappear. I can't just use it. These two are with R load 56ohm
These three are for R16ohm load.
As said, big signal, big volume, no harmonics? What did I do wrong?
However, now my 20ohm planars sing, find them no more shy.
It's like you get what you have, with a poor quality recording, you will get poor quality amplified.
I am happy.
Let me thank @adason, @Nico Ras , @widea , and the great @AKSA for this small but great sounding "wire".
Who has questions, I'll be happy to respond.
Power resistors are 56 10W non inductive and 22 (or 20, don't remember) 5W non inductive.
Keep cabling short, and that's it! 😁
See ya 😎
I am happy to see you did it and you like the sound!😀 😀👍👍 The case I am planning to use is a bit bigger, I will build it modular including a filter, but appearently that is not really needed looking at the way you built it. May take a few weeks before I can finish and listen to it, can't wait!
Harmonics are too low for the scope, probabilmente.
Try soundcard and REW!
Depends on what you want to measure and the max input of your audio interface (considering eventual voltage divider).
Congratulations, Michelag!
Here's a picture of my preamp using the same topology and presently under listening tests. I use a high beta series pass regulator to remove the grass from the laptop, and delivers about 16.75V to the circuit. Can do up to 10Vpp into 250R, so can actually drive a Beyerdynamic DT880-250 with ease. The pot is a RK27 ALPS of 20k log curve.
HD
Here's a picture of my preamp using the same topology and presently under listening tests. I use a high beta series pass regulator to remove the grass from the laptop, and delivers about 16.75V to the circuit. Can do up to 10Vpp into 250R, so can actually drive a Beyerdynamic DT880-250 with ease. The pot is a RK27 ALPS of 20k log curve.
HD
Hugh, nice PCB. I use a MC7824 on my amp and it has been happy for 17 years, The whole box is the heat sink and I run it off a USB topping DAC. I look back at my layout and some of our e-mails and see 02/02/2007 so yes 17 years ago. Also played around with binaurial circuits.
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Small thing, when it gets hot, it plays normally with high impedance cans, then I plug the 20ohm planars, it starts motorboating. Guess have to solder the 22pF cap between B and C. After my holidays
Oh, yes, for testing I was using a lousy 24V 1A brick. Already ordered a 3A one...
Ok, I'll give more than 2200uF per channel
Ok, I'll give more than 2200uF per channel