Mofo

What people are working on at the moment
simon
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#121 Re: Mofo

Post by simon »

The advice at B&Q was not to use a rattle can but furniture paint as they felt I'd get a better finish. 4 coats later, it's okay. From a distance. It doesn't seem to be particularly resilient though.
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With cheapo magnetic computer vents to allow ventilation.
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Finished
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Last edited by simon on Mon Apr 15, 2024 2:32 pm, edited 1 time in total.
simon
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#122 Re: Mofo

Post by simon »

One more as it wouldnt go on the last post.
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Under £200 all in. I use it with bass drivers so it was interesting to hear it full range at Dave's. It does lose out to a SET in the mid and treble, but the bass is nice and clean.

The 2A3 amp though... beautiful. All the wonder of valves in the mid and treble but the bass was nicely controlled too.
steve s
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#123 Re: Mofo

Post by steve s »

Loverly simon, not used mine for a year or so.. Will need to give the px4 a rest after my hols

I bought a nice 1930 pye sunburst radio case a couple of weeks ago and can't stop thinking what I could fit in it
... or I could take it down to retrotech and sell it for a £10'r next month? .. That would keep me focused on the crap I already own !
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
simon
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#124 Re: Mofo

Post by simon »

Thanks Steve, I've been trying to make more of an effort to box stuff up the last year or so...

If you do want to get rid of that old radio I might be interested, always fancied the retro look but never had one.
steve s
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#125 Re: Mofo

Post by steve s »

Its a big case simon, and needs restoration but it not wormed.. let me know if you want it
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
simon
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#126 Re: Mofo

Post by simon »

Thanks Steve, I've sent you a WhatsApp
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MistyBlue
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#127 Re: Mofo

Post by MistyBlue »

That’s a great looking case, Simon!

Nice to hear that you are getting good results with a similar setup to the one I’m aiming for.

I absolutely love the upcycling of the CPU coolers, they would make great “features” on top of an amp case, especially with the Noctua fans. A kind of alternative to the glowing valves and transformers! I decided not to do that on the design for mine, however I was sorely tempted, and the Noctua fans are surprisingly quiet (I have one on my guitar rig).
"When we're about to do something stupid, we like to catalogue the full extent of our stupidity, for future reference." - Commander Susan Ivanova, Babylon 5
simon
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#128 Re: Mofo

Post by simon »

Thanks Misty. It's a bit too smart to fit in in my play room, but I aspire to bring the rest of it up to a similar standard!

I got the CPU cooler idea from Steve S. They're 12V powered from a small 12V SMPS with buck converters to wind the voltage down to reduce fan noise. They're running about 6V but could go lower as the heatsinks runs very cool.

The larger SMPS has a fan that kicks in periodically. It's audible if there's no music or very quiet, but I'm very close to the amp, less than 2m. Normally it's unnoticeable.
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MistyBlue
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#129 Re: Mofo

Post by MistyBlue »

I used a low cost PWM fan controller on the guitar rig. I think it’s this one, although it was a couple of years ago now:

https://www.ebay.co.uk/itm/194948487077 ... R6am2o_dYw

The original 24V fan was noisy and ran flat out all the time which was a bit annoying as I sometimes play while watching TV on the sofa. I just ran it through a 12V regulator and then into the PWM controller. The NTC probe just went on the heatsink in a tapped hole next to one of the output transistors. The fan was quite expensive as they go (it's a bit cheaper now though), but I went with it because some of the guys on DIY audio spoke highly of it being quiet and I also wanted to test it out for other audio equipment as I was quite sceptical. The amp is an old Hartke HA3500 that has been modified a number of times now. I was very impressed with the fan – it is very quiet and just about silent even when the speed picks up. It was a Noctua NF-A8 PWM 4-Pin (80mm, Brown)

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"When we're about to do something stupid, we like to catalogue the full extent of our stupidity, for future reference." - Commander Susan Ivanova, Babylon 5
simon
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#130 Re: Mofo

Post by simon »

Interesting. Looks a bit more sophisticated than my setup.
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Ray P
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#131 Re: Mofo

Post by Ray P »

If anyone is interested in a 'Super MoFo'...

https://www.diyaudio.com/community/thre ... st-7655416
Sorry, I couldn't resist!
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Nick
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#132 Re: Mofo

Post by Nick »

Hmm, a lot of that added complexity would make me think that the original point of the MoFo was being lost. Also, the very different rise and fall time in that square wave display would worry me.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
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