Hi Salas,
Capacitors C2 and C2Y tandem slight mismatch was scratching my hart (my wife always saying that I have OCD related to pedantizm). So, I decided to rematch that section after some burn-in time.
Now, I have C2+C2Y combine 15,196nF of both channels.
I used my favour DE-5000 and thanks again for your advice to acquire it.
It is an asset in my small lab.
Now, I would like to reset my biasing, again.
What would be a good technique to bring VR1 to its Mid range when all are soldered in (VR2x is less critical since I'll set B+ to about 35V any way).
Thank you.
Alex
Capacitors C2 and C2Y tandem slight mismatch was scratching my hart (my wife always saying that I have OCD related to pedantizm). So, I decided to rematch that section after some burn-in time.
Now, I have C2+C2Y combine 15,196nF of both channels.
I used my favour DE-5000 and thanks again for your advice to acquire it.
It is an asset in my small lab.
Now, I would like to reset my biasing, again.
What would be a good technique to bring VR1 to its Mid range when all are soldered in (VR2x is less critical since I'll set B+ to about 35V any way).
Thank you.
Alex
If you're worried about 100MHz and up you should probably make a faraday shield around your trafo with whatever conductive mesh is available. Solder all seams and use feed-through caps at input/output. Feed-through caps are probably one of the only effective RFI filters in the GHz range. You would want something with holes smaller than 4mm. Seriously, with the possibility of very effective RFI shielding using conductive mesh, I don't know why I never see it.
Or you could put the shield around your signal circuits and keep the PSU on the outside, again using feed-through caps. You could even make multiple shields.
Or you could put the shield around your signal circuits and keep the PSU on the outside, again using feed-through caps. You could even make multiple shields.
Got one channel almost done. The coupling and output cap I am going to steal from another project. I bought 30 LED's...all were within .07 V of each other (1.82-1.89V). I found 4 matched pairs.
This is my first complex point-to-point project. It's very interesting and is taking a lot longer than expected.
Hope it works!
This is my first complex point-to-point project. It's very interesting and is taking a lot longer than expected.
Hope it works!
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I do like the Rike caps on the output.
It enhances bass performance without loosing high freq detail. There is also an impression of speed and attack on the transients. This is an alu pio cap that does not sound like a typical pio. It does not enhance the mid zone and does not sound rounded. Piano sounds full bodied. Acoustic bass is more present and detailed. A good inexpensive alternative for those that like a full bodied sound. MR are more airy but also leaner in comparison. Obbligato is not so emotional and does not have so much "byte".
It enhances bass performance without loosing high freq detail. There is also an impression of speed and attack on the transients. This is an alu pio cap that does not sound like a typical pio. It does not enhance the mid zone and does not sound rounded. Piano sounds full bodied. Acoustic bass is more present and detailed. A good inexpensive alternative for those that like a full bodied sound. MR are more airy but also leaner in comparison. Obbligato is not so emotional and does not have so much "byte".
6 months ago when i build simplistic RIAA and it sound great. Yesterday i build new folded RIAA. I put better components inside. This is changes:
Old - New
1. classic - folded
2. 2x2sk170bl - 3x2sk369bl
3. wima fkp2 - styroflex
4. cheap res - Dale, PRP
5. Nippon - Muse KZ
6. Epcos B33063 - Jantzen Z-cap Silver 0.1uF
7. Ampohm - Jantzen Z-cap Silver 3.3uF
Power supplpy is the same. Souind results? Never in my life heard worse sound, like a cheap radio, without bass. Where did i wrong, i dont know. I will change for old components one by one and try to find cause
Old - New
1. classic - folded
2. 2x2sk170bl - 3x2sk369bl
3. wima fkp2 - styroflex
4. cheap res - Dale, PRP
5. Nippon - Muse KZ
6. Epcos B33063 - Jantzen Z-cap Silver 0.1uF
7. Ampohm - Jantzen Z-cap Silver 3.3uF
Power supplpy is the same. Souind results? Never in my life heard worse sound, like a cheap radio, without bass. Where did i wrong, i dont know. I will change for old components one by one and try to find cause
Attachments
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No oscillation, R4 4,3V, Led diodes 8,3V, source resistor 130 ohm R13 3k33 for folded. Fol old version collector of Q3 is on 11V. Source resistors are 8.2 ohm R13 1k2.
First i try disconnect one 2sk369 and change R13 for lower. Then i will change Q3 connection like on old riaa. You'll be notified of the results. Don`t worry, i have to make it to work right
First i try disconnect one 2sk369 and change R13 for lower. Then i will change Q3 connection like on old riaa. You'll be notified of the results. Don`t worry, i have to make it to work right
Glad I have someone to compare these with.
Your explanation is more elaborate, but I think we agree on some of the basics. For those that think they hear poly caps 'plastic' sound, then try these.
I have a .1uf Copper Jupiter/wax interstage to put into their next, but I am still trying to fully understand the sound before making changes. Right now, just a MKP1837 .1uf
Those that want to learn what it is that we "hear" and how that corresponds to what we design.