Hi Hannes, I don't doubt they do the job just fine, as some may have some special qualities like you describe.
But I dislike "wall warts" (and to some extent SMPS in general) for other good reasons, some being aesthetic and perhaps philosophical:
1. The form factor: They usually block a few 230V outlets, and look very ungainly (if positioned visible).
2. Lack of longevity: A good linear PSU lasts what, 40 years probably. Wall wart SMPS, 10 years maximum.
3. I can't repair them.
4. I don't trust them: I have had a few generic phone chargers "explode" with a bang (no flames though).
5. They are always on, consuming some idle current, if I don't switch off the wall outlet - which I usually don't with my Hifi system.
6. Last but not least: To me they just don't match the soul or spirit I feel is inherent in a well designed and constructed Hifi device. It just feels wrong to power an elegant and well loved topology (by the designer and the users/builders) with a generic, often unstable, device made with the cheapest components possible.
Edit: Sorry for the slightly off-topic remarks.
But I dislike "wall warts" (and to some extent SMPS in general) for other good reasons, some being aesthetic and perhaps philosophical:
1. The form factor: They usually block a few 230V outlets, and look very ungainly (if positioned visible).
2. Lack of longevity: A good linear PSU lasts what, 40 years probably. Wall wart SMPS, 10 years maximum.
3. I can't repair them.
4. I don't trust them: I have had a few generic phone chargers "explode" with a bang (no flames though).
5. They are always on, consuming some idle current, if I don't switch off the wall outlet - which I usually don't with my Hifi system.
6. Last but not least: To me they just don't match the soul or spirit I feel is inherent in a well designed and constructed Hifi device. It just feels wrong to power an elegant and well loved topology (by the designer and the users/builders) with a generic, often unstable, device made with the cheapest components possible.
Edit: Sorry for the slightly off-topic remarks.
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Dear Hannes!
I found that IC from the power supply THS4031 is hard to get in PL, I could get it from Canada by ebay with extra fee for sending,
is there an equvalent for this opamp?
I found that IC from the power supply THS4031 is hard to get in PL, I could get it from Canada by ebay with extra fee for sending,
is there an equvalent for this opamp?
I don't have part numbers to give you, but here is a quote from the article in Linear Audio regarding the THS4031: ".. similar low-noise unity gain opamps can be used instead".
Hope that helps - if not, I could perhaps get you a THS4031 next time I order form Mouser.
Hope that helps - if not, I could perhaps get you a THS4031 next time I order form Mouser.
Hi Hannes, I don't doubt they do the job just fine, as some may have some special qualities like you describe.
But I dislike "wall warts" (and to some extent SMPS in general) for other good reasons, some being aesthetic and perhaps philosophical:
1. The form factor: They usually block a few 230V outlets, and look very ungainly (if positioned visible).
2. Lack of longevity: A good linear PSU lasts what, 40 years probably. Wall wart SMPS, 10 years maximum.
3. I can't repair them.
4. I don't trust them: I have had a few generic phone chargers "explode" with a bang (no flames though).
5. They are always on, consuming some idle current, if I don't switch off the wall outlet - which I usually don't with my Hifi system.
6. Last but not least: To me they just don't match the soul or spirit I feel is inherent in a well designed and constructed Hifi device. It just feels wrong to power an elegant and well loved topology (by the designer and the users/builders) with a generic, often unstable, device made with the cheapest components possible.
Edit: Sorry for the slightly off-topic remarks.
All valid reasons - this IS diy ;-)
BTW Where are you located? I was in Tisvildeleje (sp?) last weekend at the European Triode Festival.
Jan
Not all wall warts are created equal.
Many wall warts, like today's generic phone chargers, are in fact switching mode supplies which I wouldn't recommend. With wall warts I mean the heavy hitters with the transformer inside.
As I keep phono stages powered all the time - which is a good thing as they take long to stabilize - the idle current is not much of an issue to me.
Also I'm using a separate hifi rack power outlet that is not visible, so optics are also not my concern.
But this is DIY, so in the best spirit everybody can build whatever he/she favors!
Sure, lots! You will want a low-noise, SOIC8, high speed opamp that is unity-gain stable and has a relatively high output current to drive the mosfet. Also please note that the opamp is driven from the unregulated rail voltage minus 18V, so it needs to cope with about 30V rail voltage.
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I had no idea there even was such an event! Sorry I missed it - although I am not really into tubes (yet) 🙂 It is about 140 km from me, so not that close. I know the place though.
Ahh, now it makes more sense.. I had assumed you meant the cheap SMPS kind, which are so widespread now. But yes of course the good old heavy transformer type is another story! But still prefer to build my own (when I have time..).
Sure, distortion &noise measurements and simulations of the RIAA accuracy were done - it's all in the article 😉
LinearAudio is an excellent magazine 😉 and more than well worth to get the full issue!
For the impatient ones, the article can be bought also as electronic download at the LinearAudio website!
http://linearaudio.net/article-detail/2159
For the impatient ones, the article can be bought also as electronic download at the LinearAudio website!
http://linearaudio.net/article-detail/2159
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Indeed it is. I have enjoyed a couple volumes. I have to be careful though, as it keeps the DIY fires stoked if your not.
Bought some 2Sc1815Gr (10pcs for 5Euro) from ebay Spain and tested them:
1 pcs hfe= 243
2pcs hfe=250
5 pcs hfe= 260
2 pcs hfe = 267
It is in datasheet parameters. What to you think about them, are they legit ?
http://www.danomsk.ru/pdf/418718.pdf
1 pcs hfe= 243
2pcs hfe=250
5 pcs hfe= 260
2 pcs hfe = 267
It is in datasheet parameters. What to you think about them, are they legit ?
http://www.danomsk.ru/pdf/418718.pdf
The Japanese and Thai Toshiba ones that I know of have the characters in vertical print. Those like in your picture are Chinese for sure, have seen them in aliexpress very cheap. Toshiba had licensed some technology to China in the past mainly for memory and consumer products chips but who knows the exact product lines, those C1815s may be licensed, or copy.
Thanks for explanation Salas!
This is the last time when i buy obsolete semiconductors. So many fakes in this world.
This is the last time when i buy obsolete semiconductors. So many fakes in this world.
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Yes, I am getting rather tired of obsolete components as well. Too much time and effort, and you often end up with a bunch of overpriced fakes..
But have an update regarding the 2SC2547E I ordered from Dalbani:
After presenting them with the test results (hFE much too low), they offered to send replacements in the form of 2SC2547E in a TO92L package. They said they come from a sealed Hitachi box, so look forward to receiving them..
But have an update regarding the 2SC2547E I ordered from Dalbani:
After presenting them with the test results (hFE much too low), they offered to send replacements in the form of 2SC2547E in a TO92L package. They said they come from a sealed Hitachi box, so look forward to receiving them..
Got my new red board today. I have been cutting aluminum to make my rack mounted enclosure this afternoon. I am combining the " High Octane Pre-amp" with a "Pass B1" . I built a three output power supply for 48vdc, 18vdc, and 12vdc to power everything. Now time to populate the red board. Most of my life I was more likely to have a 5lb. sledge hammer and a stick welder in my hands, so this is quite a project for me. Wish me luck folks.
Thanks Hannes. Looking at your pre-amp is what got me started on this project. I am learning and having fun at the same time. What more could one ask for!
I don't know how that last picture got in there-Haha
Thanks Hannes. Looking at your pre-amp is what got me started on this project. I am learning and having fun at the same time. What more could one ask for!
I don't know how that last picture got in there-Haha
