Are you asking about the regulators that are on the schematic and BOM, with the heatsinks that fit in a 1U chassis? I don't understand your question, aside from the obvious answers of, “those are the specified regulators” and “the heatsinks fit the package, the PCB footprint, and the chassis.”
What are you getting at? Please clarify if this didnt answer your question.
Want to try something fancier? I’d really like to try these, they are made by an engineering firm local to me (neat!) and seems to be very well regarded -
https://sparkoslabs.com/discrete-voltage-regulators-audio-power-supply/
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I've got those Sparkos in my Pearl Two. Quite a bit more expensive than 7x24's, but at least I did not have to buy a larger enclosure to fit super regulators.
Before those I had regulators from AMB labs (sigma78 and 79, based on a TI regulator chip). I can't say I noticed a difference, but then again, my audio memory is not long enough to remember what it sounded like before. It was and still is a great sounding phono stage.
Before those I had regulators from AMB labs (sigma78 and 79, based on a TI regulator chip). I can't say I noticed a difference, but then again, my audio memory is not long enough to remember what it sounded like before. It was and still is a great sounding phono stage.
@6L6
That's in interesting idea too. I think niffy here tried those.
I saw these at Parts Connexion
https://partsconnexion.com/products...5-15-0v-regulator?_pos=2&_sid=872c5778d&_ss=r
Parts Connexion is close to me but not, I think, NewClassD
That's in interesting idea too. I think niffy here tried those.
I saw these at Parts Connexion
https://partsconnexion.com/products...5-15-0v-regulator?_pos=2&_sid=872c5778d&_ss=r
Parts Connexion is close to me but not, I think, NewClassD
Hello,
The specified heat sink is this one: 531002B02500G.
https://www.mouser.com/datasheet/2/2/Aavid_01112021_Board_Level_Cooling_Extruded_5310-1953660.pdf
The heat sink in my bin for use with the in hand Burning Amp P3 PCB’s is this one: 513002B02500G
https://www.mouser.com/datasheet/2/2/Aavid_01112021_Board_Level_Cooling_Extruded_5000-1953731.pdf
The extrusion shape is the same for both. The specified item has two mounting screw holes and a larger cutout where the regulator attaches. (reduced surface area for attached TO 220)
Just wondering a bit, why one over the other?
The specified 7815 and 7915 regulators have a TO-220FP package with an insulated metal tab.
Also wondering a bit how this was specified over the regulators with an exposed bare metal tab?
Thanks DT
The upgrade discrete regulators look interesting.
The regulator I have been using to power the P3 breadboard first stage runs at just a few degrees above ambient without a heat sink.
The capacitance multiplier in the P3 is a good tool. I am going to add that feature to the Pass H2 on my bench.
The other side of the coin is also true. With a much improved PSRR Regulator you do not require a very quiet input.
Perhaps a Triad 18volt DC switching wall wart supply used with the upgrade discrete regulator could be a solution for many of the jfet projects we play with.
Thanks DT
The one I think about is the one attached (datasheet). But it is relative thick (10mm). So it should be checked especially one side where a small capacitor is relative close to the heatsink. By "eye-catch" it should work. But there are really many of those "drop-in" replacements. The others I have seen are thinner but have lesser performance or very little documentation. That is the reason if I should use a replacement I would go with the Sparkos.
Once upon a time a got a LSK170A octet from the Store. It was at the beginning of my DIY career where I did not know much about Idss ranges and which are most used for DIY projects. The A-grade has Idss from 2.6 to 6.5 mA and not good for most projects (which needs higher Idss).
But for this project they seems ok?
So if they are a small upgrade from the 2SK209 in terms of noise then it could be a good reason to "get rid of them"?
But for this project they seems ok?
So if they are a small upgrade from the 2SK209 in terms of noise then it could be a good reason to "get rid of them"?
Attachments
Hello Meper,
I would give the Linear Systems LSK170A a try - for sure. Those are excellent JFets. Ultra low popcorn noise,...
If you are willed, you can build a second PEARL 3 -board and use 2SK209 GR (Toshiba) in there. All other
parts on the 2 sets of boards the same, I think it would be very, very difficult to hear a real difference.
My opinion. But those are the active devices in the first stage of PEARL 3.
If you start to play with the OPAmps and other active devices - it could become difficult - more complex.
I tested a few Opamps in my build. As long as those are 'good' OPAmps for audio use - very difficult for me
to hear real major differences. It is very subtle. Till now, I only listened to a few Texas Instruments-Opamps. Have a few JRC- (NISSHINBO / Japan Radio Corporation) and LT-Opamps in the queue.
And then there are such a lot of other 'factors' in an audio-chain...
You've got an excellent vinylplayer with a very good pickup. I think all will be on a very high level.
But we are allways searching for that 'little thingie' making the sound a bit better...
Cheers
Dirk
I would give the Linear Systems LSK170A a try - for sure. Those are excellent JFets. Ultra low popcorn noise,...
If you are willed, you can build a second PEARL 3 -board and use 2SK209 GR (Toshiba) in there. All other
parts on the 2 sets of boards the same, I think it would be very, very difficult to hear a real difference.
My opinion. But those are the active devices in the first stage of PEARL 3.
If you start to play with the OPAmps and other active devices - it could become difficult - more complex.
I tested a few Opamps in my build. As long as those are 'good' OPAmps for audio use - very difficult for me
to hear real major differences. It is very subtle. Till now, I only listened to a few Texas Instruments-Opamps. Have a few JRC- (NISSHINBO / Japan Radio Corporation) and LT-Opamps in the queue.
And then there are such a lot of other 'factors' in an audio-chain...
You've got an excellent vinylplayer with a very good pickup. I think all will be on a very high level.
But we are allways searching for that 'little thingie' making the sound a bit better...
Cheers
Dirk
You use 10 ohm source resistors?
I have decided for the ADA4898-2 opamp. It was the one with lowest noise I could find. It is a smd and I like the idea not to have any sockets for such a sensitive circuit. I also think the difference between high-end opamps is so small so it is not worth the effort.
Yes, my TT + cartridge plays very good. I will probably try my ultrasonic record cleaner this weekend and a vinyl flattener is on the way.
I will use the LSK170A for the project unless some will chime in and tell me it is a bad idea
I ordered the Sparkos 7815/7915 replacements. Then I can give feedback how they work. But first I need a kit!
I have decided for the ADA4898-2 opamp. It was the one with lowest noise I could find. It is a smd and I like the idea not to have any sockets for such a sensitive circuit. I also think the difference between high-end opamps is so small so it is not worth the effort.
Yes, my TT + cartridge plays very good. I will probably try my ultrasonic record cleaner this weekend and a vinyl flattener is on the way.
I will use the LSK170A for the project unless some will chime in and tell me it is a bad idea
I ordered the Sparkos 7815/7915 replacements. Then I can give feedback how they work. But first I need a kit!
My 2 cents:I will use the LSK170A for the project unless some will chime in and tell me it is a bad idea
The SK209 - taken from the same strip - have pretty close IDSS figures as was mentioned in the thread. As a result, you would have a decent channel-to-channel balance even without measuring individual devices
Also, I would assume the SK209 grade is chosen so that the total IDSS works in the circuit with the standard values, especially so that the voltage drop across R1 will be within limits.
If you use the SK170, the IDSS may be all over the place, unless the shop where you bought them pre-selected them, so channel-to-channel balance may be way off. This would still work since the circuit has feedback. But if the total IDSS would be on the high side, then the voltage drop across R1 would become too high and the circuit may not work properly, i.e. without lowering the value of R1.
So if you can measure and calculate the result, go for it, else build as designed. Also, if you have an MC cartridge the noise difference "may" be noticeable, with a MM cartridge it will most certainly not make any difference.
The SK170A is an octet purchased from the DiyAudio Store. I don't assume that the IDSS figure will be "all over the place"
But I don't know how close they are matched or who did the matching
It is grade A so IDSS probably around 4 mA.....would be a good guess.
I read the feedback from 6L6 as he has tried LSK170 in circuit and based on listening test he like 2SK209 better. This could be a good reason to use the 2SK209.
My cartridge is a MM (5 mV output).
But I don't know how close they are matched or who did the matching
It is grade A so IDSS probably around 4 mA.....would be a good guess.
I read the feedback from 6L6 as he has tried LSK170 in circuit and based on listening test he like 2SK209 better. This could be a good reason to use the 2SK209.
My cartridge is a MM (5 mV output).