The Kuartlotron - keantoken's simple error-correction superbuffer

It seems C2 has wrong polarity on my board. Please reverse.
BR Sika
Cap.reverced.
Now the earlier clipping is on the positive side.
Is this any advantage putting NP capacitors here?
 

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Cap.reverced.
Now the earlier clipping is on the positive side.
Is this any advantage putting NP capacitors here?

You could try a small 20-100uf NP Nichicon ES from the positive to negative rail (not connected to ground). (C4 & C5)

But no, it's nothing to get worked up over other than the fact that say the ES series like Joachims used are higher quality than some capacitors. You'd have to ask Keantoken if one on C1 and C2 would work.

Are you using Silmic II's? They're fine.
 
@keantoken: can BC550C and BC560C be substituted with BC550CG and BC560CG, respectively? Or will it require tweaking some other part values? I can't seem to find BC550C and BC560C ("no longer manufactured" as per the online seller I usually buy from). Thanks in advance.
 
bc560c is the transistor model.
Extra codes after that last C mean something that can be decoded from that manufacturer's datasheet. Usually date, and/or location of manufacture and/or whether ROHS, or shape of lead outs or taped or ....... etc.
These final codes have NOTHING to do with performance. The first 6 define the transistor performance as in the datasheet.
 
Thanks Destroyer, AndrewT and keantoken.

I bought the parts and assembled it point to point. Actual soldering is pending. I have some more questions:

1) couldn't get 56 ohms trimmer. Will 50 or 100 work in its place?
2) couldn't get 3.6k trimmer either. Got 5k. Hope it works?
3) ditto 2.7 M trimmer. Will a 1.5M fixed in series with 1M trimmer do?
4) do the legs of the trimmer work like a regular pot? My understanding is 1 is input, 2 wiper and 3 ground. Is this correct?
5) I'm not clear what to measure when adjusting trimmers R1 and R9.

Thanks for being patient with my noob questions.
 
the wiring of the trimmers depends on what you need them to do.
If you want/need a voltage reducer then you wire as a three terminal potentiometer.
Although actually it is a 4 terminal device where pin3 is common to both the input and to the output, i.e. in = 1-3 and out = 2-3

If you need a variable resistor then you wire it as a two terminal device, where the wiper gets shorted to either 1, or 3, depending on whether you need ClockWise (CW) to increase, or decrease, the VR value.

pots/trimmers come in few values E3 mostly, 1, 2, 4.7or5, 10
Choose the e3 value above the maximum you would ever need.
For the 2M7 VR, I would use 1M pot + 2M2 fixed, to give range of 2M2 to 3M2
 
1: Use 50 ohms.
2: Should be fine, if not optimal.
3: The 0 DC offset point may be outside of the range of the trimmer. I would use 2.2M with the 1M trimmer so that you have plenty room before and after 2.7M (which is just a guess for what the optimal value is)
4: Maybe. For long trimmers sometimes the last pin is the wiper. In this circuit the wipers are always shorted to one of the pins. Whether you short the wiper to one pin or the other determines which direction the screwdriver will turn, but won't matter for the circuit.
5: This is DC offset. Measure DCV from output to ground with nothing connected to the input. Adjust R9 so that it's as close to 0 as you can get.
 
Finally completed the build. I made so many mistakes I lost count:D

Luckily for me fellow forumer baswamin who had successfully completed this build, patiently helped me to troubleshoot as I bungled from one folly to another, and with my persistence not to give up on my first point to point build, it has paid off. Hats off to you, baswamin:worship:

And it's sounding pretty damned good. I am on my seventh track (Sibelius' Symphonic Poem Finlandia), and I think it's already shamed the DCB1 clone I built. Very clean, very transparent, deep tight bass, clear separation and quite dehomogenised. I like it.

Some details:
DC offset is about 2.9 to 3 mV on both channels. Pot is 10k log (CITEC, UK). My source has impedance of 100 ohms, and the power amp has input impedance of 100k. I'm not sure if 10k is the optimal value. I'm just using what I have on hand. I can try a 50k log, if that will be a better match. All parts are strictly common garden variety bought from the local electronics market, absolutely no exotics used.

It's been a steep learning curve but well worth the sonics. Thanks keantoken for sharing this wonderful design.