"...will have lower operating temperatures and lower thermal noise as a result."
That makes sense. I was trying to get a handle on this on another thread (or two). For phono preamps and MC pre-preamps low noise is important. I would think that using 1/2W devices would be preferred if there was room on the board.
The general advice has been that Vishay/Dale have the lowest noise. But at 0.1Uv/V is it that much lower than, say, Takman's 0.3uV/V and in a meaningful way? Or PRP's -30db? (according to them). Or the -42 db of the near-unobtanium-grade naked foils Vishay TX2575?
And I expect there are other noise mechanisms -- other than thermal -- at play that have pundits and salesmen waxing poetic about "warmth" and such.
That makes sense. I was trying to get a handle on this on another thread (or two). For phono preamps and MC pre-preamps low noise is important. I would think that using 1/2W devices would be preferred if there was room on the board.
The general advice has been that Vishay/Dale have the lowest noise. But at 0.1Uv/V is it that much lower than, say, Takman's 0.3uV/V and in a meaningful way? Or PRP's -30db? (according to them). Or the -42 db of the near-unobtanium-grade naked foils Vishay TX2575?
And I expect there are other noise mechanisms -- other than thermal -- at play that have pundits and salesmen waxing poetic about "warmth" and such.
Finished mine after a 6 week wait for a transformer.
Still need to put it in a box.
Two records in and im going to enjoy this pre-amp.
Isolation by plastic ono band sounded great.
Photos to come when in a chassis.
Thank you Oliver.
Still need to put it in a box.
Two records in and im going to enjoy this pre-amp.
Isolation by plastic ono band sounded great.
Photos to come when in a chassis.
Thank you Oliver.
Here's mine finished and sounding very nice.
Made a maple and walnut veered case for the cover which was fun, finished in Danish oil. Last photo shows it in place.
Made a maple and walnut veered case for the cover which was fun, finished in Danish oil. Last photo shows it in place.
That's great news. Really pleased to see these builds getting completed and most of all, being enjoyed.
That's a DC blocker....stops DC getting off the mains inlet to the transformer and making it mechanically buzz.
Oliver, did you find replacement for Audiophonics.fr?
I received my boards today, now I am looking for a transformer, Tiger Toroids quoted £50 (transformer) + £40 (shipping) - pricey. I am considering getting this one from ebay: https://www.ebay.com/i/192498606475...DQOvd7aLpwsnxHKdVnbKICbD3s88fjYxoC-RgQAvD_BwE
but not sure about quality...
I have never used one personally but a good few have and reported no issues.
I did order an EI transformer from Chinese outfit, but I dont recommend them for one box builds.
Need to get them far far away from the PCB.
Toroidy.pl make really nice transformers.
Other than that, I think taking a punt in the one linked wont hurt..and a R core is a decent traffo.
It's cheap enough anyway.
Where are you based? If you're in the UK I have a contact at Tiger and may be able to get you a better deal on the postage.
What if the AC input to the HV is 230v-0-230v and I only have 0-230v AC.
How do I connect then?
How do I connect then?
Common the centre pair as it were. Pretty sure the ebay ad shows you this if you look at the detail.
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Yes it's a 115 115 traffo so you have to common the centre pair, this gives you 230v input.
There is a wiring diagram on the traffo and it is pretty easy to check with a Multimeter....once someone tells you how to do it lol
Observation from the cheap seats:
I've been mostly just monitoring this thread so I don't know the precise requirements of the transformer but I've seen descriptions of custom units with multiple outputs.
Why not get two transformers, one to handle each voltage?
In the States Antek -- Transformers - Page 1 - AnTek Products Corp -- seems to have a reasonable selection that might serve to keep your project going.
Just a thought...
I've been mostly just monitoring this thread so I don't know the precise requirements of the transformer but I've seen descriptions of custom units with multiple outputs.
Why not get two transformers, one to handle each voltage?
In the States Antek -- Transformers - Page 1 - AnTek Products Corp -- seems to have a reasonable selection that might serve to keep your project going.
Just a thought...
yeah, I was thinking about this as well, although I couldn't find transformer with 165V secondary...
Youd have to have it custom wound, which probably doesn't save you a while lot in all honesty
