Author Topic: Audi-O-Moron 40W amplifier  (Read 871 times)

Online markc

Re: Audi-O-Moron 40W amplifier
« Reply #15 on: May 06, 2019, 12:22:33 PM »
Well done!! Great looking amp. Something to be proud of!!
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Offline irengineer

Re: Audi-O-Moron 40W amplifier
« Reply #16 on: May 07, 2019, 08:06:58 AM »
Love that steampunk type styling! This is hugely impressive, I hope it sounds awesome too!


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Offline rudie.lamprecht

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Re: Audi-O-Moron 40W amplifier
« Reply #17 on: May 08, 2019, 05:20:24 PM »
Excellent work. Would love to hear what it sounds like.
Rock On
Rudie

Offline Telephono

Re: Audi-O-Moron 40W amplifier
« Reply #18 on: May 09, 2019, 03:43:24 AM »
Magic stuff! Well done.  :2thumbs:

Offline Ufudu

Re: Audi-O-Moron 40W amplifier
« Reply #19 on: May 11, 2019, 11:02:56 AM »
Thanks for the comments.

How does it sound? Well, in my option it sounds good enough for me to replace this setup with the Audiomoron:





Some sound observations:

I am currently running the driver stage pentodes in triode mode, so the loop gain is significantly lower (as you can see from the frequency response curves).

- I can definitely detect a difference in sound between  the output tubes (in this case 6550 and 6l6, I will try others today). This may be because of the lower loop gain; at some stage I will reconnect the driver in pentode mode and see if I can still hear the difference;

- I cannot detect any sound difference when I change the output stage bias from 30 - 60mA, although the simulation shows an improvement in distortion, the difference is too small for me to hear. So I have been running the tubes at the lower bias;

- Initially I was concerned that the high end was "too bright", possibly even distorting certain instruments like cymbals etc.

- The seemingly bright high end was dependent on the source recording, and high end audio files seem to be fine;

- The more I listened the better it seemed to sound. I have worked out that if I am slightly stressed my hearing seems to suffer and music can sound like an annoying noise!

- I have now moved the amp to play into my Jamo C809 speakers instead of the Monitor Audio Silvers and must say I am pleasantly pleased with the sound overall.





Online Nidri

Re: Audi-O-Moron 40W amplifier
« Reply #20 on: May 11, 2019, 07:56:36 PM »
Such an impressive project.
BTW I think Audiomoron is perhaps the most amazing name for an amplifier ever.
It's a name you are guaranteed to never forget.
So delightfully un-PC.

P.S. What's that valve amp on the bottom shelf? Another DIY amp? Maybe that's the AudioNitwit;)
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Offline Ufudu

Re: Audi-O-Moron 40W amplifier
« Reply #21 on: May 12, 2019, 05:43:49 PM »

P.S. What's that valve amp on the bottom shelf? Another DIY amp? Maybe that's the AudioNitwit;)

No, not quite! That's one of Karel Mar's kits (slightly modified)

Offline Mars

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Re: Audi-O-Moron 40W amplifier
« Reply #22 on: May 15, 2019, 10:11:08 AM »
I have worked out that if I am slightly stressed my hearing seems to suffer and music can sound like an annoying noise!

Interesting observation, Ufudu. I have also found that stress reduces perceived audio quality.
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Offline Qualityten

Re: Audi-O-Moron 40W amplifier
« Reply #23 on: May 31, 2019, 10:48:11 PM »
Interesting observation, Ufudu. I have also found that stress reduces perceived audio quality.
And makes tinnitus worse, or at least the perception of it. On the other hand, music almost always reduces stress for me.