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Superreg on a Hackernap

Lm317/337 will handle the voltage as long as the drop across the regulator isn't more than 30 odd volts.

Pete
 
The LM317/337 isn't a bad place to start and even better if you use a Tracking pre reg as per the acoustica website. As Pete says as long as the LM317 doesn't see more than 37 volts from input to output then it'll work fine.

All of the Jung style superregs (including the Sjostrom) will need to have the opamp supply limited to the opamps max voltage or less, a zener or suchlike at the opamps output and probably an adjustment to the reference voltage.

Here's an outline of what I did on my Hackernap.

[URL=http://s869.photobucket.com/user/John_Luckins/media/ALWSR50v_zpsed3dabd6.jpg.html][/URL]
 
I don't have a hackernap but i do have the Avondale Ncc200 boards with VBE boards. Is this idea the same as regulating the front end of the board? If it is then VBE is the way to go it sounds much better, a totally different amp.
 
As a first step the Vbe is certainly the way to go. FWIW I tried the front end Vbe and found it could be improved upon with the "Fetlington" mod mentioned in the thread. It was then that I tried the much lower output impedance ALWSR above as a replacement for the Vbe Cap Multiplier and this was noticeably better in my HackerNap. I've stuck with it for a year now and am very happy with it.

John
 
I've heard John's Hackernap at quite a few stages during his evolution with it. It sounds amazing, much much to complex for most people to accomplish though.
 
Colin Barron said:
I don't have a hackernap but i do have the Avondale Ncc200 boards with VBE boards. Is this idea the same as regulating the front end of the board? If it is then VBE is the way to go it sounds much better, a totally different amp.
Click to expand...

Do you mean better than an unregulated front end (rather a given, I'd have said), or that VBE is a better type of regulation than other types of regulation?

BugBear
 
I used Sulzer super-regs on my HackerNAP with OPA551/2 op amps which support 60V and 80V total supply voltage. There is also the OPA445, none of these are particularly cheap.
 
It is a long time since anyone wrote on this thread, so firstly I hope everyone is OK and well. The coronavirus lockdown has lead me to extracting a partly finished Hackernap from the bottom shelf in my office. Change of Hi Fi to Quads and tube OTL amplification, has left it unrequired until now. However I thought I'd connect it up and finish it. Then I thought about the super reg modification! I don't have a lot of space for super regs, but I may be able to put a Veroboard above my soft start module. I will have to lay it out and see if I can accommodate 2 John Luckins super regs. I hope some of the luminaires from years ago are still around and can answer a few questions. John Luckins schematic notes a C4 in the reference. There is no value against it. Does anyone know what this value is? Secondly, is it the intention to replace the CRCRC completely with the super regulator board? I have 40v traffo so I am not sure what my output voltages are from the CRCRC, I can measure them from my working Hackernap though. I have the fetlington mod if that makes any difference.. I note that Johns schematic has 55V going in and is set to 55V as an output. I thought that there would be a drop across the Super reg, but this doesn't appear to be the case. ?

I hope someone is still around who can answer my queries, in which case I will see if I can get the bits to create 4 super regs for my 2 Hackernaps.

Regards to all

Dave
 
I think the issue is that the opamp used on the superreg is limited in voltage output. I think John has managed to tweak it to give more but i dont know how. Other options to replace the on board regulator are the Avondale VBE board or the Avondale HCR board
 
timH said:
I think the issue is that the opamp used on the superreg is limited in voltage output. I think John has managed to tweak it to give more but i dont know how. Other options to replace the on board regulator are the Avondale VBE board or the Avondale HCR board
Click to expand...


Have a search on here, there is a thread about Tedys PowerReg.... Like SuperTeddyReg but for amps....
 
For the ALWSR at the higher voltage all that was needed was to use a cap multiplier with a zener across the capacitor to reduce the voltage fed to the opamp. All other components can be the same as long as they have a high enough voltage rating. I've been running this for some two years now with no problems. The positive rail of the front end benefits the most as it sinks a signal dependant current and seems to benefit from the much lower impedance of the ALWSR.

I'll respond to messages and try to clarify this again at the weekend as am flat out at work at the moment. A better drawing would be good.

John
 
John
thank you for your reply, I have been researching ALWSR and I think I can see whats going on. I am unsure about C4 - I think this should be 100uF (?) low esr capacitor, and I am not sure where the negative supply for the op amp should be grounded - on the power input rail? Also where is the 0v sense rail grounded. I presume all capacitors will be electrolytic unless they have a low esr rating. Finally, I am slightly confused that there is 55v input and 55v output. I thought there should be a drop of say 2.5-5v across the regulator. I've checked with RS and I can get all the components next week, so I can get building. I have an weeks holiday next week enforced by the company I work for. This is why I thought i'd get on and finish my unfinished hackernap. Thank you for your help, look forward to your response. Keep well.
Dave
 
batjodel said:
John
thank you for your reply, I have been researching ALWSR and I think I can see whats going on. I am unsure about C4 - I think this should be 100uF (?) low esr capacitor, and I am not sure where the negative supply for the op amp should be grounded - on the power input rail? Also where is the 0v sense rail grounded. I presume all capacitors will be electrolytic unless they have a low esr rating. Finally, I am slightly confused that there is 55v input and 55v output. I thought there should be a drop of say 2.5-5v across the regulator. I've checked with RS and I can get all the components next week, so I can get building. I have an weeks holiday next week enforced by the company I work for. This is why I thought i'd get on and finish my unfinished hackernap. Thank you for your help, look forward to your response. Keep well.
Dave
Click to expand...
I think the following links may help you, after the recent group buy for ALWSR there was a build thread, and I have been recording my efforts in putting ALSWR in a NAXO. Plenty more stuff to find on pfm about ALWSR but these are up to date and include links to a google docs BOM and the latest ALWSR online manual plus plenty of advice and experience.
 
In the Reference section you will find Hackernap info thread as well as a build thread. And the ALWSR reference files
 
batjodel said:
Finally, I am slightly confused that there is 55v input and 55v output. I thought there should be a drop of say 2.5-5v across the regulator
Click to expand...
I believe the main input is the 60v line. The output from the regulator is 55v and it also goes to both the vref bank of led’s and the VBE for the supply voltage to the opamp
Tim
 
Yes, what timH said. The output of the reg (OP1, 55V) feeds the "front end zener Vbe" (top left of sketch) and the "Reference" (bottom left) as well as the load. You have to cut the track between OP1 and pin 7 of the chip so that the chip can be supplied from the zener Vbe and replace ZD1 with the output of the 7 x led string. R9= 670, rationalised to 680 ohm and R8= 1960, rationalised to 2k0 to give gain of 4. R4 is removed and replaced with 18k and 40k (39k will do) in series, 18k to led and 39k to 0V. 10uF 50V goes from SRIN to join between 18 and 39k. I think John also mentioned keeping TPR in (wired as per ALWSR manual) but using a green led instead of R3, and possibly replacing R2 (1k0) with something like 150R to put a few mA through the TPR led (Acoustica mod, also keep the cap across this led per ALWSR manual).
I'm sure someone will correct me if I'm wrong but I believe that is the gist of it.
 
Just as an aside I’ve been thinking about the flea option mentioned earlier in the thread. If we combine John’s VBE and Vref circuits for the opamp Vin and + in like so
0-E89-D712-3-FA3-4-FD8-A6-DE-9-F25-A10-F42-EF.jpg

would this work?
 
You aren't getting 55v out from an opamp rated for +/-18v max supply rails. More seriously, there is good reason to use discrete external pass transistors - which is deal with the thermal and current demands.

TBH I don't think using the 797 offers a significant benefit in the circuit John Luckins posted; and is fast enough you'd need to watch for & sort-out the stability issues it could bring.
 
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