Yay! New toy

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Nick
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Re: Yay! New toy

Post by Nick »

Thats right I sort of remember now :-)
Resistance isn't futile it's V / I.
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Greg
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Re: Yay! New toy

Post by Greg »

Tony Moore wrote: Sun Jan 10, 2021 1:10 pm By the way, does anyone know if Leo from Nottingham is on this forum or where I might get in touch with him? It was Leo who got me into the 1541 chip and Pedja's DAC implementation. I have an email address for him and pinged it but no response yet,

Cheers,
Tony
Hi Tony
I’d give Richard on the WAD Forum a shout. I bet he still has contact info for Leo.
Tony Moore
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Re: Yay! New toy

Post by Tony Moore »

Hi Greg,

Thanks, good idea, I'll give him a shout.

How are you keeping? What are you up to these days?

Cheers,
Tony
Tony Moore
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Location: New Brighton

Re: Yay! New toy

Post by Tony Moore »

Right, well....moving on with the Transporter... :x

I looked up a few circuits around that I could try in place of the stock output stage in the Transporter and came across the FET-ishator. :lol:

This is a Lampizator derived idea that is based on a FET as the principle device rather than a tube. I thought I've give it a try and had some boards made up with a slightly modified version of the cct. The originally specified FET has been obsolete for a few years and even the ones meant to be equivalent are also obsolete so I went with a surface mount device, BF861C. The circuit has a MOSFET follower and that's it really. As simple as it gets. Today, after messing around with the resistor values I hooked it into the Transporter and into my HD83 and Senheiser phones.

Wow. :shock:

I am gobsmacked. I had to switch back to the stock outputs just to make sure I wasn't imaging things. Nope, with the stock output the sound is muddled and tizzy and although it's perfectly acceptable I guess it bears no resemblance to the output using the simple FET/MOSFET circuit. Here the space has opened up around my head, I'm hearing things in 3d that I've not heard before. It's wonderfully detailed but not at all tizzy.

So all in all it was a very well worth it experiment and I'll be drilling the case and adding a pair of phonos to the back for the permanent installation. Don't get me wrong, this is not perfect of course as I'm not using the differential outputs that the DAC can provide plus I don't have a low pass filter (yet) so all sorts of HF junk will be getting out, however the headphone amp will no doubt help here! I would not dream of connecting this to a SS amp in this form though!

In my opinion the TDA1541 still sounds better but this has significantly closed the gap.

ps. Still not managed to get in touch with Leo. Richard has not heard from him for years either. :(
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