I like it a lot too, it is very simple and from what I read it sounds amazing. I am planning to build it.
But I use the components I already have. They are BC550C and a TIP42C for Q1 and Q2, 43 ohm 5W and 20 ohm 5W for R5 and R6.
Using these the THD drops a bit.
According to LTSpice you can use 16 ohm headphones if you increase the voltage to 18 V. However the temperature of the components also increase because of:
Q2: 830 mW vs 546 mW
R5: 844 mW vs 477 mW
R6: 402 mW vs 227 mW
The harmonics 'profile' also changes, but keeps interesting imo:
Thinking about it it is tempting to use a laptop power supply of 19 Volts...
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The only information I could find was here: https://www.diyaudio.com/community/threads/aspen-headphone-amp.152031/page-57
1. This is how I will build it:
2. These are the results I hope for:
3. Distortion using 16 ohm headphones:
4. Distortion using 16 ohm headphones solved by increasing the voltage to 18 Volts:
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Credits go to Aksa and Nico Ras for the original design.
The resistor represents an automatic fuse, a so called polyswitch.
The yellow ferrite ring for the inductor I got from an old power supply and I wound the gnd and + wire together, 14 turns.
That is a bit of an experiment, but I think it will not hurt:
In LTSpice once you got the graph window with the SIN wave (.tran 0 25ms 0 1u), you right-click that window.
Choose 'View - FFT'. I have these parameters set:
Click 'OK'.
Press 'CTRL-L' and it shows the error log where you see the THD.
I also do not know everything LTSpice and electronics other than what I learned on this forum and at school 100 years ago so keep that in mind.
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@widea, thanks for the hints, I'm slowly going through that also / Nico Ras thread.
just for my understanding, what cans do you (usually) use?
I've got a 20ohm planars audeze LCD,
Sony mdr 7506 with 64ohm
Intime miyabi (Japan) iem 22ohm,
And considering building a 500ohm Aurora borealis clone...
Difficulty is to drive planars, as you can easily imagine.
just for my understanding, what cans do you (usually) use?
I've got a 20ohm planars audeze LCD,
Sony mdr 7506 with 64ohm
Intime miyabi (Japan) iem 22ohm,
And considering building a 500ohm Aurora borealis clone...
Difficulty is to drive planars, as you can easily imagine.
I only got two:
- Beyerdynamics DT770 PRO 80 ohm with a passive correction filter (see https://diyaudioheaven.wordpress.com/passive-filters/ thanks to Solderdude for the schematics)
- Sennheiser HD202 that I only use when experimenting
Yes, I looked at that and considered building something similar. But I am always curious about something 'out of the ordinary', not to say Whammy is not like that. But there is something about that circuit, the simplicity, the harmonics, the comments of Aksa and Nico Ras that points to an exceptional sound quality and that attracted my attention...
My biggest problem is that designers try to chase miniscule harmonic distortion and always end with this clinical character that all sounds the same, boring. it is like an naturally ugly girl stripped of all her make-up. Listeners fatigue is very much related to clinical sound you need warmth and character not bland and lifeless.
What should I look for? The least possible with a nice amount of second?
Where is High (Hugh?)'s paper?
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All my old designs was aimed at zero distortion, it was a sin to add anything to the pureness. You can confirm this with Hugh and our private discussion from almost 20 years ago. I could eventually not listen to music for more than an hour and had to take a break. The simple answer was to add this simple circuit in front of my power amp and all the joy of listening, not hearing (that is when your wife talks to you) came back into my life.
Interestingly, all Hugh's amps are named after his daughters, not some silly name with numbers in it. The reason for this is simple, he created things that he cherishes and have a human, warm and friendly and loveable character. Did I get this right my friend.
Interestingly, all Hugh's amps are named after his daughters, not some silly name with numbers in it. The reason for this is simple, he created things that he cherishes and have a human, warm and friendly and loveable character. Did I get this right my friend.
I fully understand your point.
So I'm looking to implement a higher voltage supply to be able to drive 16ohm cans.
You talk to a diyer who listens to r2r DACs with no filters, no oversampling, and tube output stages. So what I dislike is exactly the boring aseptic sound.
So where can I find Hugh's paper?
So I'm looking to implement a higher voltage supply to be able to drive 16ohm cans.
You talk to a diyer who listens to r2r DACs with no filters, no oversampling, and tube output stages. So what I dislike is exactly the boring aseptic sound.
So where can I find Hugh's paper?
Not only second, but well distributed monotonic degression. That is the biggest problem with differential inputs which tend to cancel the harmonics and creates the sound of everything else. These simple designs dates from the sixties and seventies, call it grassroots if you like, then followed the chase after distortion specifications in marketing literature and hi-fi was ruined forever.