Link to the pcb film.
http://forum.zelfbouwaudio.nl/download/file.php?id=76174
Link to the powerpcb film.
http://forum.zelfbouwaudio.nl/download/file.php?id=75874
http://forum.zelfbouwaudio.nl/download/file.php?id=76174
Link to the powerpcb film.
http://forum.zelfbouwaudio.nl/download/file.php?id=75874
boards availability
Hi!
I'd like to try your design. Do you plan to make and sell the boards/kits?
Have you compared sound to other phono stages with mm cartridge?
Herman
Hi!
I'd like to try your design. Do you plan to make and sell the boards/kits?
Have you compared sound to other phono stages with mm cartridge?
Herman
Hello Herman,
i have compared the Mini-Me with several phono stages like,
- phonodude PhonoDude deel 1
- project tube box SE. Pro-Ject Audio Systems
- and several opamp stages.
I like the Mini-Me best, but this is my own subjective opinion.
I shall try to describe the differences.
The opamp stages have a detailed, good defined sound with not so wide soundstage.
The project tube box sounds like the opampstages with less detail.
The Mini-Me sounds like the Phonodude a much wider soundstage, with more live in it, i like to listen to it. Just the sound i expect from a tube stage.
Further no noticable humm or noise.
About the PCB i have no intention to produce them. But it is very easy to make them yourself.
Cheap and Easy Toner Transfer for PCB Making
Ronny
i have compared the Mini-Me with several phono stages like,
- phonodude PhonoDude deel 1
- project tube box SE. Pro-Ject Audio Systems
- and several opamp stages.
I like the Mini-Me best, but this is my own subjective opinion.
I shall try to describe the differences.
The opamp stages have a detailed, good defined sound with not so wide soundstage.
The project tube box sounds like the opampstages with less detail.
The Mini-Me sounds like the Phonodude a much wider soundstage, with more live in it, i like to listen to it. Just the sound i expect from a tube stage.
Further no noticable humm or noise.
About the PCB i have no intention to produce them. But it is very easy to make them yourself.
Cheap and Easy Toner Transfer for PCB Making
Ronny
Interesting. I'll be watching. I love those tiny tubes and have wanted to do something with a batch I have.
Hi, what is the size of the PCB' s and what instructions do I need to send to a PCB maker to acquire the right PCB?
Today i build one MC stage for testing purpose.
I discovered a fault in the PCB at the MC pre input, i shall correct that a.s.a.p.
...
I did not use the Zener in the MC pre because there was no humm at all. I shall modify the schematic a.s.a.p.. For the heatersupply i used an extra LM7806.
I am very pleased🙂
Hi koifarm,
sorry for posting this so late in the thread.
You mention an additional LM7806 for the heatersupply
which is not included in your schematics.
Is that needed for the MC stage?
regards
Hello Sebuschi,
i am still supporting this thread and use this preamp in my phono setup.
The 7806 is not needed. V5 en V6 of the mc pre have the heaters in serie on the 12v supply with is stabelized with the 7812.
I used the 7806 only to test one channel of the mc pre. I neede just 6v for one heater.
Ronny
i am still supporting this thread and use this preamp in my phono setup.
The 7806 is not needed. V5 en V6 of the mc pre have the heaters in serie on the 12v supply with is stabelized with the 7812.
I used the 7806 only to test one channel of the mc pre. I neede just 6v for one heater.
Ronny
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Hello Sebuschi,
i am still supporting this thread and use this preamp in my phono setup.
The 7806 is not needed. V5 en V6 of the mc pre have the heaters in serie on the 12v supply with is stabelized with the 7812.
I used the 7806 only to test one channel of the mc pre. I neede just 6v for one heater.
Ronny
Hi Ronny,
many thanks!
I have one more question: Do you have a list of the condensers (more specific than 220µF/250 V) with the types or even the brands of the condensers?
Regards
Achim
hello im looking for the capacitor c5 and c 8 what kind of capacitor ist it
im only find mica but only 5%
or this 40 St. axiale Kondens. 200pF/630VDC, Philips (B174)!! | eBay
soory for my poor english
im only find mica but only 5%
or this 40 St. axiale Kondens. 200pF/630VDC, Philips (B174)!! | eBay
soory for my poor english
I used nos film/ foil cap. But you can also used the ones in your link or link below.
2pcs-PHILIPS (BC) KP 200P (0.2nF) 630V 1% Axial Polypropylene Capacitor - KP464 | eBay
I have some spares. In can send them to you. Please contact me personal.
2pcs-PHILIPS (BC) KP 200P (0.2nF) 630V 1% Axial Polypropylene Capacitor - KP464 | eBay
I have some spares. In can send them to you. Please contact me personal.
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Measurements with 100 Ohm at the input.
Amplication = 3000x
SNR = -77db
At what output level? Guessing at 1Vrms, that is 333uV at the input, implying an EIN of 47nV, which is impossible! Something is not right here. Under realistic conditions the MC input SNR is not likely to be better than 50dB.
It is possible that i interprate the measurements wrong. In reply 11 and 12 i ask how to read the graph. No one anwser.
What was your output signal voltage level?It is possible that i interprate the measurements wrong. In reply 11 and 12 i ask how to read the graph. No one anwser.
Your software probably uses averaging to reduce the noise floor, which will make the results seem quieter than they really are.
Incidentally, your choice of MC input stage is quite noisy. You can improve the SNR by perhaps 4dB by connecting the two triodes in parallel and using a simple anode load resistor, instead of stacking the two triodes.
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are this the capacitor c8 in your preamp
10x 200pF 63V 0.2NF 63V 1% EMZ KP HI_END FILM/FOIL CAPS FOR AUDIO ! | eBay
and c5 like this one
50x NEW ERO MKP1839 (axial mkp1837) 8.2nF 400V CAPS 1% HI_END TUBE AUDIO ! | eBay
ps thank you for the answer
10x 200pF 63V 0.2NF 63V 1% EMZ KP HI_END FILM/FOIL CAPS FOR AUDIO ! | eBay
and c5 like this one
50x NEW ERO MKP1839 (axial mkp1837) 8.2nF 400V CAPS 1% HI_END TUBE AUDIO ! | eBay
ps thank you for the answer
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