thanks for the tips.
now a question that makes me blush and that you will laugh: a smaller resistor R12(100 ohms) means 150 ohms or 47 ohms?
now a question that makes me blush and that you will laugh: a smaller resistor R12(100 ohms) means 150 ohms or 47 ohms?
thanks for the tips.
now a question that makes me blush and that you will laugh: a smaller resistor R12(100 ohms) means 150 ohms or 47 ohms?
47
That R12 opposes or releases some current to the 4K7 so you can trim the 2SK170 draw there between channels.😉
P.S. Rest of builders pay no special attention and don't get perplexed, its special Roberto values and matrix board build for MM with 2SK170 he only got, we debug.
The PSRR depends on the specific transistor you use in the C-multiplier. You'll just have to try many different ones and see which kind has the lowest ripple at the output. If you follow through, I'll be eager to hear your results.
Simulation is usually optimistic on the PSRR here because quasi-saturation is not modeled. The reason simulation is accurate for the BC5xx/3x7 is because these transistors don't have much quasi-saturation to speak of.
Also, you might want to add some diodes so the transistor is more protected from reverse discharges.
If your output capacitance is too much, your transistor will go over SOA while charging it.
Simulation is usually optimistic on the PSRR here because quasi-saturation is not modeled. The reason simulation is accurate for the BC5xx/3x7 is because these transistors don't have much quasi-saturation to speak of.
Also, you might want to add some diodes so the transistor is more protected from reverse discharges.
If your output capacitance is too much, your transistor will go over SOA while charging it.
Only 100uF bcs those I found in an unused good quality pair. I will make it then, feed ripple and see output on the scope. I have in hand exotic transistors even but I wanted to see with a very common one first.
Looks good to me, but I don't know if Vcesat behavior is directly responsible for PSRR in a C-multiplier, unless it's operating in the quasi-sat region. That's why I say to just test a number of transistors.
Hi Salas,
I am a tube guy and built few amps, but no preamp or phono stage. I am trying to figure out how do I start with vynil. I start reading the thread( got to page 50) and it is quite a long road to the end.
First, I need to decide what System (TT) to buy( Many recommend to begin with Debut Carbon witch has a Ortofon 2M if Im not mistaken). I also have an old Sanyo Q25(it is PLL direct drive turntable) that has no cartridge, but many say that the arm is not very good( I am not sure why). I could built a heavy plinth and get a better tonearm. Just dont know where to start
Second, I need the phono stage and I like your design very much. I just registered on a
group buy for your phono stage. What are the posts where you described the final schematics. I am not sure what parts should I procure. I need a little help, otherwise it will take me a month to figure things out( eventually I will finish reading the thread).
Thank you so much for your help.
Best regards,
Radu
simplepleasuretubeamps | Thermionic Tubes and Sound Revelations
I am a tube guy and built few amps, but no preamp or phono stage. I am trying to figure out how do I start with vynil. I start reading the thread( got to page 50) and it is quite a long road to the end.
First, I need to decide what System (TT) to buy( Many recommend to begin with Debut Carbon witch has a Ortofon 2M if Im not mistaken). I also have an old Sanyo Q25(it is PLL direct drive turntable) that has no cartridge, but many say that the arm is not very good( I am not sure why). I could built a heavy plinth and get a better tonearm. Just dont know where to start
Second, I need the phono stage and I like your design very much. I just registered on a
group buy for your phono stage. What are the posts where you described the final schematics. I am not sure what parts should I procure. I need a little help, otherwise it will take me a month to figure things out( eventually I will finish reading the thread).
Thank you so much for your help.
Best regards,
Radu
simplepleasuretubeamps | Thermionic Tubes and Sound Revelations
Old Sanyo stuff is good quality. Plus Q25 was from their prime line. Some probably don't like the fact that its arm has a joint with a screw varying its headshell overhang arguably compromising rigidity. Still a 0.03% wow & flutter -70dB rumble accurate speed 6kg high vinyl era Japanese TT with a properly configured stock mat is no slouch. You could further enhance it at a point as you say. If still in good working order better invest in a good cartridge for it than in a new entry level quality TT of light mechanics and cheap cartridge. Get a Dynavector 10X5 high output MC 2.5mV (more in practice) and make the 43dB gain version of the folded simplistic. No need to read the whole thread, go to post#1 link#3 and download its build guide. For its key obscure semiconductors and other parts ask in its GB thread. Also read the last chunk of pages here than the old chunk to see some relative PCB builds and comments. After you will spin some records on the Sanyo via the Dyna through the folded simplistic to your tube gear, let us know if it was a bad plan or not. BTW nice amp in your blog.😉
Salas,
Sounds fantastic. I appreciate your advise. I will definintely let you know when time comes.
I actually sold the PSE posted in the blog and am working to build a similar. I made some changes in the new amp, and hopefully for a better sound. I upgraded the OT from Lundahl to Monolith, and some other small upgrades( filament bias resistors from inductive to non-inductive). I need more sensitive speakers too. I have small reflex Alpair12p at 92dB.
I am excited to build your phono stage and see the results.
Thank you again.
Cheers,
Radu
Sounds fantastic. I appreciate your advise. I will definintely let you know when time comes.
I actually sold the PSE posted in the blog and am working to build a similar. I made some changes in the new amp, and hopefully for a better sound. I upgraded the OT from Lundahl to Monolith, and some other small upgrades( filament bias resistors from inductive to non-inductive). I need more sensitive speakers too. I have small reflex Alpair12p at 92dB.
I am excited to build your phono stage and see the results.
Thank you again.
Cheers,
Radu
Definitely you will need bit bigger & sensitive speakers to enjoy the tubes & vinyls better.😀
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Looks impressive and I am sure it sounds excellent.
At the beggining of this thread I saw that you used DL-160. Looks like it is more affordable. Do you think that would be a good fit to the Plus Q25? It is not as heavy as the 10X5, but still within the TT specs.
Radu
At the beggining of this thread I saw that you used DL-160. Looks like it is more affordable. Do you think that would be a good fit to the Plus Q25? It is not as heavy as the 10X5, but still within the TT specs.
Radu
Its discontinued now but you can still get the DL-110. Great value cart. Very close to the 160.