Thank you for your advice !
I think I have made me not well understood.
If you look at the picture, you wil see that it is described from Vacuum State to use 51 ohm resistors at that location. I thought the reason for thouse resistors was to drop the volt down to about 15 v.
Since that was not very sucsessful, and the lamps did not light, I started to worry that something might be wrong.
It is calming to hear that the 15v circuit draws about 10 mA. To me that sounds realistic.
Since 34,5 v is within of the maximum of 36 v, the 51 ohm might have other function than drop resistors. Maby to separate them from parasit on each other? What is Your opinion on on these resistors ?
The reason for my locasjon of the LM317, was the lack off Space, I didnt knew the heat dissipation and last, it was close to the power inlet connector.
Again thanks for advice, and I wil check the Sreg light later to night.
Sincerely
Frode
Attachments
To night I tryed to connect the Lm317 to the Sreg. I soldered a adjustable 100 ohmresistor across the 317. When switching on my b+ who was adjusted to 300v, was fast going up above 340v, so I switched off. I adjusted the volt a bit down, and tryed again, but stil it was high and rising. The volt on 317 was unstabil from 1-6v.
With 3 adjustment pots, high voltage and a unstabile low bias volt I am afraid my testing/experimentasjon might end up with a failure in the Sreg.
Is there anyone who can calculate the value of the resistor over the Lm317 when I want 15v out of it. The startpoint are 34,5 v and the circuit draws about 10mA
Sincerely
Frode
With 3 adjustment pots, high voltage and a unstabile low bias volt I am afraid my testing/experimentasjon might end up with a failure in the Sreg.
Is there anyone who can calculate the value of the resistor over the Lm317 when I want 15v out of it. The startpoint are 34,5 v and the circuit draws about 10mA
Sincerely
Frode
Frode,
What do you mean by "I soldered a adjustable 100 ohm resistor across the 317."? You need to have a voltage divider connected between output and ground, with the adjust pin on the wiper, as shown here.
I would advise setting the output voltage on the LM317 before you connect to the op-amp. As a starting point, mine has 120R between output and adjust, and 1K3 between adjust and ground, which gives just under 15V.
Alex
Hello Alex,
Thank you for sharing the photos of your Sregs showing your implementation of an additional LM317 for the opamp power supply and yes when I gonna do
this I will definitely also not hack around with PCB traces so maybe I will follow your construction if it can't be done properly the way I intend it to do.
By the way there is also some interesting remarks from dice45 over Allen's super reg here on diyaudio where he talks among others over the importance of C6!
In case that you don't already know this it can be found here under 3rd in #22:
Anyone has a copy of the superreg of Allan Wright's design
Regards,
Günter
Ah, I had forgotten about that thread. Lots of interesting stuff, and also some pretty negative things said about Allen. Doing business with him seems to have been a little like my dealings with Arthur Khoubesserian at Pink Triangle/Funk Firm - they are full of enthusiasm and brilliant original ideas, but aren't naturally business minded.
Alex
Hi everyone,
I'm a bit late to the party, I suppose.
After three years of intensive work of planning, constructing and building my RTP3D I’ve finished the build. My only source is a DAC, thus I omitted the phono stage and multiple inputs.
Especially challenging was the construction of the chassis, everything is based on custom made Aluminum panels by Schaeffer (aka Panelexpres).
Maybe worthwhile to explain are the solder tags, which I built with wooden strips and pure silver cable sleeves from WBT.
Here are some pictures:
power supply:
Preamp:
I want to especially thank this forum and all it's contributors in this thread, which was of great help for me and really encouraged me to build this preamp. The sound I'm getting out of it is just gorgeous, I'm just so happy!!
All the best to all of you
Henning
I'm a bit late to the party, I suppose.
After three years of intensive work of planning, constructing and building my RTP3D I’ve finished the build. My only source is a DAC, thus I omitted the phono stage and multiple inputs.
Especially challenging was the construction of the chassis, everything is based on custom made Aluminum panels by Schaeffer (aka Panelexpres).
Maybe worthwhile to explain are the solder tags, which I built with wooden strips and pure silver cable sleeves from WBT.
Here are some pictures:
power supply:
Preamp:
I want to especially thank this forum and all it's contributors in this thread, which was of great help for me and really encouraged me to build this preamp. The sound I'm getting out of it is just gorgeous, I'm just so happy!!
All the best to all of you
Henning
Hi Henning,
Your RTP3 is beautifully built. Mine has nowhere near the attention to detail in yours!
Would you mind telling us what amplifier and speakers you are using with the RTP3D?
I hope you have years of pleasure listening to music through it. My only comment is that you will never hear how good the RTP3 sounds when fed from a top-class vinyl source...
Alex
Your RTP3 is beautifully built. Mine has nowhere near the attention to detail in yours!
Would you mind telling us what amplifier and speakers you are using with the RTP3D?
I hope you have years of pleasure listening to music through it. My only comment is that you will never hear how good the RTP3 sounds when fed from a top-class vinyl source...
Alex
Hi Alex,
many thanks for your feedback. Your documentation and expressed thoughts around your build on your website were one of the main sources of inspiration and motivation for me!
My poweramp is a Pass Labs XA30.5 and my speakers are Reference 3A La Suprema.
You are very right about the missing phono experience and I have to admit, that it was a tough decision for me to omit that part of the RTP3D. Hopefully I'll stay comfortable with that decision... Well, I've already put a lot of efford in my digital frontend and I have to focus my energy and financial ressources somehow. My next project for the upcoming years will be the build of Allen Wright's DPA-300B poweramp. Having such great result with the RTP3D that feels like a consequent next step for me.
Henning
many thanks for your feedback. Your documentation and expressed thoughts around your build on your website were one of the main sources of inspiration and motivation for me!
My poweramp is a Pass Labs XA30.5 and my speakers are Reference 3A La Suprema.
You are very right about the missing phono experience and I have to admit, that it was a tough decision for me to omit that part of the RTP3D. Hopefully I'll stay comfortable with that decision... Well, I've already put a lot of efford in my digital frontend and I have to focus my energy and financial ressources somehow. My next project for the upcoming years will be the build of Allen Wright's DPA-300B poweramp. Having such great result with the RTP3D that feels like a consequent next step for me.
Henning
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Please help me with 2 components of the early RTP3C from 1998 !! (The one with IRF 830 MosFets).
It is the 2 cathode resistors in the line amplification stage named R1, and the 2 resistors in the SLCF cathodes, named R2. I have not been able to find values for those anywhere.
The RTP3C comes in at least 2 versions, one from year 1998 shown in the Preamp Book with MosFeets, and a later one from year 2000 shown elsewhere. The late one is quite close to RTP5.
I have bought the Preamp Book and some Super Regs from Vacuum State, so I have contributed a little bit for the IP.
Having bought the book some years ago, I now plan to build the FVP5A first, then the ´simple´ RTP3C, and then eventually the RTP5D or the late RTP3C, to form my own opinion on the different configurations.
Thanks in advance
Arthur.
It is the 2 cathode resistors in the line amplification stage named R1, and the 2 resistors in the SLCF cathodes, named R2. I have not been able to find values for those anywhere.
The RTP3C comes in at least 2 versions, one from year 1998 shown in the Preamp Book with MosFeets, and a later one from year 2000 shown elsewhere. The late one is quite close to RTP5.
I have bought the Preamp Book and some Super Regs from Vacuum State, so I have contributed a little bit for the IP.
Having bought the book some years ago, I now plan to build the FVP5A first, then the ´simple´ RTP3C, and then eventually the RTP5D or the late RTP3C, to form my own opinion on the different configurations.
Thanks in advance
Arthur.
Hi Henning, impressive build. Have you considered Allens PP-2C ? Its a PP KT88 amp with 6H30 front end. I recall reading he favoured this amp to the DPA-300B. The schematic is attached in this thread. There is a build thread in a forum somewhere on the planet, I cant remember where and cant find, but can look again for it sometime if your interested.
Using EL34 for allen wright's pp-2c
Using EL34 for allen wright's pp-2c
Yes I am planning one too, but with the Polish Toroid OT´s with Cathode Feedback and Ultra Linear coupling, like advised in Menno van der Veens tube amp book. He calls the coupling Super Triode, even if it is not a real triode coupling. It has higher output, lower output impedance, and lower distortion. It looks extremely interesting, and then with Allens power supply type, and input stage. Could be unbeatable.
Hi Luke, many thanks for your reply. I've found a quote from Allen himself, saying that he actually prefered the 300B against the KT88:
"(...) the KT88 amps you saw at my place are the only ones that will be built. They would have to cost exactly the same as the dpa300B amps but don't sound near as good -- and who wants an expensive KT88 amp? And the expected higher power is not readily obtained in practice . Hence until we come out with a quite different design with 100 watts or more -- using a rather special tube not normally used in audio -- the dpa300B when equipped with KR300BXL's or KR842 tubes will be the most powerful at 25watts"
I would be very grateful if you could optain the thread with the PP-2C build sometime. Some inspiration is always highly appreciated.
All the best
Henning
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I've never seen a schematic for Allen's 300B version - I guess it never went as far as public release, and now Allen isn't around they are justifiably holding onto the IP. I note that on the VSE schematics page there only one for the PP1. Is there one for the DPA-300B floating round the Web somewhere??
Alex
Alex
Thanks Henning, that was in 2004 he said that, I thought the PP-2C was a product, anyone else on the forum know? EDIT: Just looked on the schematic for PP-2C and its 2004. Interesting that he says it costs the same as a 300B amp, those tubes are 1K a pair.
I found it:
Allen Wright's - PP-2C eindversterker - Pagina 3 - forum.zelfbouwaudio.nl
I found it:
Allen Wright's - PP-2C eindversterker - Pagina 3 - forum.zelfbouwaudio.nl
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I have not had any progress yet in this area.
I bought a Super Reg kit from Allens old company, that is build but not testet yet, and some PCB´s for the HPHV Super reg, not build yet.
In the meantime I have build an MFA Reference E88CC preamp, that sounds very good, but that not uses a Super reg yet, and a modified Marantz M7 preamp with 12AY7, that is not testet yet.
My build will also take some time. I am going to get some experience with Super Regs first.
I bought a Super Reg kit from Allens old company, that is build but not testet yet, and some PCB´s for the HPHV Super reg, not build yet.
In the meantime I have build an MFA Reference E88CC preamp, that sounds very good, but that not uses a Super reg yet, and a modified Marantz M7 preamp with 12AY7, that is not testet yet.
My build will also take some time. I am going to get some experience with Super Regs first.