You know how I like to do it, I've posted it here often enough. As you say, a VBE multiplier with a zener diode for required voltage minus drop across trannie.
For ultimate speed, use IRF MOSETs, they are also cheap and easily available, but bear in mind the greater voltage drop across them.
I use MJE 15030/15031 rather than BD 139/140 for two reasons: one, they have a higher voltage rating and I generally like to use BJTs at least twice the rated voltage, and two, in my case, they are asked to dissipate over 3W of power, and again, I prefer to use something at least twice the actual requirements, so the BDs are too close a shave for my taste.
Is it worth the time and trouble? In my book, yes it is, beats the classic capacitor multiplier easily for sound quality. And the cap multiplier beats the usual resistor/cap combo just as easily. You reap all the benefits of separate PSU lines for the input stage, VAS and the predrivers.
You may find that you have as many answers to this question as the number of people you ask.
My personal choice is simple and is determined by personal experience:
* for normal use, I use German made Fisher & Tausche capacitors, my most frequently used values being 10,000, 4,700 and 2,200 uF/63 or 80V;
* for "price no object" projects, I use ? made Siemens Sikorel caps. Question mark because some years ago, Siemens of Germany merged its capacitor production with Matsushita of Japan, so I don't really know who actually makes them at this time, and
* for PSU filtering, I use Wima MKT series, for signal Wima MKS series. If unavailable, I will use Siemens models, and Plessey also has some good ones.
I shy away from Japanese capacitors because they sound a little shrieky to me, at least the ones I tried from Elna, Nichicon at al., but I will use Panasonic caps. The other reason is that Japanese products are most copied in China, so my chances of getting a Chinese copy are far greater than with European makes.
Unfortunately, these days, that is a major concern.
Not likely if bypassed with a lower value metalized Wima MKT cap (e.g. 220 nF).
Even the smaller value caps tend to be missing these days. These days, the norm seems to be 10-22 uF caps, of unknown origins and quality, probably the chepaest they could lay their hands on.
Agreed on poor PSRR though.
Nah. Bypassing those electros is mostly based on folklore. Do the math - how 'bad' must a 10,000 uF electro be before 0.22uF starts to make a difference? And when it does, there is the inductance of the wiring from the caps to the load that prevents the 0.22uF to make a difference where it matters - at the load!
If they have to help they should be at the load not // to the electrolytics.
But, increasing the electrolytics will still increase the line harmonics spray, from a low impedance, and those 0.22uF's wont do anything against that.
Jan
Demain , i don't notice high frequency issues with my silent pressings , nor on the white DD Pressings , definitely not any less than the black ones. As to wearing out LP's , i have never experienced that also , how many times would you have to play a pressing to notice degradation ...
Buying special BS CABLES For 10K to hear your pre/amp combo as insisted by the manufacturer should hit your filter too , talk about needing to protecting the public
If I recall, they said that decoupling the motor from the chassis helped to reduce vibrations transmitted to the LP during pressing and made a clearly audible difference. It works in turntables.
Last edited:
Now there's a non-sequitur, I can't believe you actually said that. The nonsense here lately is hard to bear. They said vibrations while the LP cooled after pressing not recording.
Wrong. It can be fully modelled, and the results of the usual insufficient engineering precisely understood - makes it clear why much audio starts to sound rather unsavoury at decent volume levels - there are no mysteries!
What is a mystery is why barely anyone takes any of this sort of stuff seriously ...
Sorry you feel that way. Here's a source, and the link. There's a similar statement in an actual Kassem interview somewhere in Stereophile several years back. I can look that one up as well, if you're interested. BTW, I have the highest respect for your work.
Quality Record Pressings - Wikipedia, the free encyclopedia
"And just as ambient temperature, humidity and variations in steam and water pressure affect the quality of a vinyl record, so do the minute environmental vibrations from nearby equipment. Unwanted harmonic vibration transmitted to the die during the pressing process causes distortion of the record’s grooves and other noise as well as other unwelcome changes in the physical structure of the grooves on a record. QRP uses custom-designed press isolation pads to mitigate the effect of these vibrations."
Last edited:
Now, I don't personally buy reissued LPs, I have all the original pressings of rock, classical, jazz, etc. that I want, maybe too many actually. But it's heartening to see interest in good recordings, especially from novices and young people. After all, the old master tapes will be worthless some day no matter how carefully they're stored. It's nice to have fresh pressings available of popular recordings so that people can hear them with good quality without all the noise and distortion on old, worn out copies.
Up Hill Rayma , up hill, take the cake .....
I'm used to a university research environment where people have very strong opinions on many things, and often disagree intensely. It doesn't bother me at all.
- Status
- Not open for further replies.