Tube Preamplifier 6J1.
Hi , someone know how is the performance of this cheap preamplifier ?
Some time i listened that changing the tubes chinese 6J1 for 6AK5 or 5654 good quality tubes , the sound is good enough..
Is a good option for limited budget ?
Santiago
Hi , someone know how is the performance of this cheap preamplifier ?
Some time i listened that changing the tubes chinese 6J1 for 6AK5 or 5654 good quality tubes , the sound is good enough..
Is a good option for limited budget ?
Santiago
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I have a similar one, it's okay. It would profit from a higher anode voltage but you'd have to change a lot of the parts to do that though. The case is ugly but that's probably just my opinion but I'd take out the blue LEDs which illuminate the tubes. To do that you have to desolder the sockets, at least on mine it was.
The price is quite high though, the cheaper ones got the same parts tolerance and quality. You can get it with a really nice metal case for ~28$ or without case for 12$ (shipped from China).
The price is quite high though, the cheaper ones got the same parts tolerance and quality. You can get it with a really nice metal case for ~28$ or without case for 12$ (shipped from China).
I've got one of these and it's good for what it is.
There is a mod here: 6J1 China preamp thoughts if you get hum.
I changed my tubes out for 5654GW and it is definitely an improvement.
Not the best preamp in the world but for the price, it is good to play with and experiment.
There is a mod here: 6J1 China preamp thoughts if you get hum.
I changed my tubes out for 5654GW and it is definitely an improvement.
Not the best preamp in the world but for the price, it is good to play with and experiment.
No, it's this preamp, it got no OPs or even transistors in the signal path, just the pentode tube wired as a triode.
I've now seen the video. It's a headphone amp (not a preamp) and the tube is not a 6J1, it's a E180F, on similar amps it's a 6J9P. And I don't think the 5532 OPs are appropriate as headphone output stages, that's asking for distortion.
You can also look at fx-audio tube-03 with a dc-dc boost 12v to 100v converter.
Very nice with GE 5654w.
I seen another 6j1 with dc-dc boost on aliexpress.
I'll search and put a link if so.
Very nice with GE 5654w.
I seen another 6j1 with dc-dc boost on aliexpress.
I'll search and put a link if so.
That would be ideal, the rise of the anode voltage got a great potential sound quality improvement. To change the board to 100V would practically mean to build a completely new one.
I've found the FX-Audio Tube-03 on ebay but I'd appreciate it very much if you could help with an Aliexpress link. I get excellent search results on google, ebay, amazon etc but I seem to fail on Aliexpress a lot. I get always tons of irrelevant search results and dozends of them (if not hundreds) are duplicate results. 🙁
Thank you for your suggestion!
I've found the FX-Audio Tube-03 on ebay but I'd appreciate it very much if you could help with an Aliexpress link. I get excellent search results on google, ebay, amazon etc but I seem to fail on Aliexpress a lot. I get always tons of irrelevant search results and dozends of them (if not hundreds) are duplicate results. 🙁
Thank you for your suggestion!
I'll try that one without tone control :
2018 New TIANCOOLKEI TUBE 01 bile preamp tube amplifier preamp bile buffer 6J1 MINI HIFI preamplifier DC12V-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
Search for" fx-audio tube-03 " you'll find a lot, i got mine from eBay.
Edit // tube-03 is perfectly biased, 100v, Pentode working as triode with 120R cathode and 3.3k anode (7.5ma bias).
Just the pot volume is unusual, just a variable resistor in an inverting opamp stage (ne5532) with 22k fixed input resistor and pot acting as a 0 to 50k variable resistor.
2018 New TIANCOOLKEI TUBE 01 bile preamp tube amplifier preamp bile buffer 6J1 MINI HIFI preamplifier DC12V-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
Search for" fx-audio tube-03 " you'll find a lot, i got mine from eBay.
Edit // tube-03 is perfectly biased, 100v, Pentode working as triode with 120R cathode and 3.3k anode (7.5ma bias).
Just the pot volume is unusual, just a variable resistor in an inverting opamp stage (ne5532) with 22k fixed input resistor and pot acting as a 0 to 50k variable resistor.
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TYVM!
That circuit got the advantage it doesn't change the in- or output impedance and if the pot isn't in line with the signal it doesn't produce scratching noises.
That circuit got the advantage it doesn't change the in- or output impedance and if the pot isn't in line with the signal it doesn't produce scratching noises.
ICG, did you find Tube-03 on Ali?
That one claims it boosts dc to 150v, but capacitors seem to be low v rated.
TIANCOOLKEI Tube Amplifiers Audio Board Amplificador DIY Kits Fever Bile Pre amplifier Hifi 6J1 tube headphones amplifier-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
That one claims it boosts dc to 150v, but capacitors seem to be low v rated.
TIANCOOLKEI Tube Amplifiers Audio Board Amplificador DIY Kits Fever Bile Pre amplifier Hifi 6J1 tube headphones amplifier-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
The page doesn't work for me, it says article not found. Maybe they don't want it to show in Germany?
As for the capacitors, there are several possibilities. The most logical would be to create the 150V with a cascade/voltage doubler or more in series. The capacitors are in series and therefore lower the capacity/current but increase the voltage rating and the effective voltage. The cascade needs a bunch of diodes and capacitors and AC voltage.
Another possible expaination would be they use film capacitors for the anode voltage, which have usually a much higher voltage rating and the electrolyte caps are. I can't tell though because I can't see the article.
They could also have a buck converter on the board and the low rating capacitors are just there to buffer the input or the voltages for the control ICs. because of high frequency of the converter a small film capacitor might be enough.
To make fake claims is ofcourse still a possibility though. That happens a lot on chinese sellers unfortunately. They usually don't just straight out lie but increase the numbers in the specification slightly.
As for the capacitors, there are several possibilities. The most logical would be to create the 150V with a cascade/voltage doubler or more in series. The capacitors are in series and therefore lower the capacity/current but increase the voltage rating and the effective voltage. The cascade needs a bunch of diodes and capacitors and AC voltage.
Another possible expaination would be they use film capacitors for the anode voltage, which have usually a much higher voltage rating and the electrolyte caps are. I can't tell though because I can't see the article.
They could also have a buck converter on the board and the low rating capacitors are just there to buffer the input or the voltages for the control ICs. because of high frequency of the converter a small film capacitor might be enough.
To make fake claims is ofcourse still a possibility though. That happens a lot on chinese sellers unfortunately. They usually don't just straight out lie but increase the numbers in the specification slightly.
No, it says the page/article cannot be found. I don't expect the link to be wrong, it's much more likely they don't want the page to be displayed in some countries/areas.
Strange thing both links re working for me...
That Tiancoolki board is red with a vertical dc-dc converter and 100v rated Grey caps... Not very confident in...
In tube-03 Dc-dc is made with a uc3843a close to 75khz, exaxt schematics as that one except I don't get smd cap values :
https://danyk.cz/noteb_en.html
That Tiancoolki board is red with a vertical dc-dc converter and 100v rated Grey caps... Not very confident in...
In tube-03 Dc-dc is made with a uc3843a close to 75khz, exaxt schematics as that one except I don't get smd cap values :
https://danyk.cz/noteb_en.html
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