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JSR03 - information

Started by Keljian, June 13, 2005, 04:54:06 PM

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peranders

I can see your disappointment. The pcb can take 3-5 times of disoldering even if you have professional desoldering tools so I can imgaine how the pcb looks like by now.

Anyway, the regualtor is a classic and the topology works very good in various applications.

Feel free to come back if you want to upgrade your "simple" regulator.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Keljian

Quote from: perandersI can see your disappointment. The pcb can take 3-5 times of disoldering even if you have professional desoldering tools so I can imgaine how the pcb looks like by now.

Anyway, the regualtor is a classic and the topology works very good in various applications.

Feel free to come back if you want to upgrade your "simple" regulator.

I'd love to upgrade it, but if I were to upgrade it I would go for boutique parts all the way through and your design doesn't support that

I have been looking at using another circuit from diyaudio to clean up the sound, but to be honest, I can't see the benefit, because I can't tell the difference between the "simple" regulator, and the more advanced jung.


To be completely honest, the simpler solution sounds BETTER than the jung.. The bass slam is much better, and the amp seems faster
http://www6.head-fi.org/forums/showthread.php?p=1469609#post1469609
(if you want details)

as for the state of the board, don't ask, there are solderpads that have come off, there was one track lifted, and misc other problems, it really is not in a good state.

BTW, thankyou for your tireless support, really you've been fantastic with all the help you gave me, and advice in general :)

peranders

Quote from: KeljianTo be completely honest, the simpler solution sounds BETTER than the jung.. The bass slam is much better, and the amp seems faster
http://www6.head-fi.org/forums/showthread.php?p=1469609#post1469609
(if you want details)
Since you eventually got the Super regulator working, do you still think that LM317 is better? The answer doesn't have to be "no" just to please me.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Keljian

Quote from: peranders
Quote from: KeljianTo be completely honest, the simpler solution sounds BETTER than the jung.. The bass slam is much better, and the amp seems faster
http://www6.head-fi.org/forums/showthread.php?p=1469609#post1469609
(if you want details)
Since you eventually got the Super regulator working, do you still think that LM317 is better? The answer doesn't have to be "no" just to please me.

Better is a relative term. I think with the 317 there was more bass slam, but on the other hand I think the sound is cleaner with the jsr. I've put some more caps on the output of the jsr and that seems to have alleviated the problem a bit, there is still a "hiss" from the headphones at high volume

peranders

Do you have hiss even with a unconnected amp or with particular sources? Do you use a PC and a soundcard?

I think you should ask other M3 builders if they also have hiss so you can leave out that it is the M3 design. You may have oscillations. Have you checked with an oscilloscope how this hiss look like?
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Keljian

Quote from: perandersDo you have hiss even with a unconnected amp or with particular sources? Do you use a PC and a soundcard?

I think you should ask other M3 builders if they also have hiss so you can leave out that it is the M3 design. You may have oscillations. Have you checked with an oscilloscope how this hiss look like?

Turns out the hiss is due to the dac I have connected atthe moment (tried another source) Will work on changing the power supply to the dac in the near future

peranders

Is it a commercial DAC or have you built it yourself?
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Keljian

Quote from: perandersIs it a commercial DAC or have you built it yourself?

it's a guzzler dac as per here: http://www.mellowparenting.demon.co.uk/guzzler/usbdac.html

At the moment it uses a maxim switching DC-DC converter, has 3000uF worth of capacitance on the power rails and is powered by the usb port on my computer.

I have a LM7806 kicking around and a few transformers around, so I am thinking of creating a simple power supply for it

peranders

From what I can see the designer has no (or little) control over the emi emissions. What about the emission over 100 MHz?

This is the hard thing about designing DAC's, make them "pure". Put a radio near the DAC and see or hear what you'll get in garbage.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Keljian

Quote from: perandersFrom what I can see the designer has no (or little) control over the emi emissions. What about the emission over 100 MHz?

This is the hard thing about designing DAC's, make them "pure". Put a radio near the DAC and see or hear what you'll get in garbadge.

No garbage - it could be due to the fact that the aluminum case is grounded.

I think the problem is the power.. will experiment in the coming weeks.

peranders

If you don't have tested with a FM or AM radio do that! This is a very cheap spectrum analyzer. Turn on and off your dac then you'll see what it transmits. Also using a DC-DC converter together with high fidelity ciruits need extra attention. The converter transmits both in wires and in air.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Keljian

Quote from: perandersIf you don't have tested with a FM or AM radio do that! This is a very cheap spectrum analyzer. Turn on and off your dac then you'll see what it transmits. Also using a DC-DC converter together with high fidelity ciruits need extra attention. The converter transmits both in wires and in air.

you're right...  I get a bit of static on the radio when I put it right on top of the dac

peranders

Quote from: Keljian
Better is a relative term. I think with the 317 there was more bass slam, but on the other hand I think the sound is cleaner with the jsr. I've put some more caps on the output of the jsr and that seems to have alleviated the problem a bit, there is still a "hiss" from the headphones at high volume
How about the slam and cleanness? Is the LM317 better or do you prefer the Super Regulator? Have you done anything to reduce the EMI problem of your DAC?
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

Keljian

the sound is a bit "thinner" overall

I haven't had time lately to work on the dac - I have my final exams for the year coming up in less than a weeks time and that is my primary focus

peranders

I'll guess you mean thin sound with the super regulator? You are sure that all parts are working properly? It might be that you'll have a clearer sound which you aren't used to.

The regulator works still I'll believe? Have you modified it anything?
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff