The Sontec thread! <ATT. BUILDERS - C22 & C23>

[thedug]

^^ Bump ^^

Also, has anybody implemented a bypass switch?
Is there a 4pdt switch for balanced true bypass the best way to go?

Doug

 

[[silent:arts]]

a question to the caps:
what kind / type / brand did you use (in the filter boards) ?

looking for the parts I can't find any equal brand / type from 39p to 2u2. and I can't find any 39p film or foil cap.

what did you use, and where did you buy ?

another cap is the 5p silver mics - would 4p7 be ok ?

I want to build a "baby sontec" (2he, pots, JH992-24 for the amps I've in the box, NE5534 for the filters), but sourcing the caps gets me crazy. :roll:

 

[[silent:arts]]

thanks :thumb:

 

[[silent:arts]]

btw, what was your total cost (everybody who built this yet) ?

the "baby version" won't be cheap (sourcing the parts right now). the "elma switched all discrete opamp" version must me much more expensive. how much did you spend for the parts at the end ?

 

[Infernal_Death]

I haven't kept track of the costs but i guess around 300 Euros. But keep in mind i used cheap NE5534 and no expensive rotary switches. Just normal pots. So i guess my version surely is at the low end of costs of this project (with Jaakko's being at the top end :green: )

Flo

 

[[silent:arts]]

[quote author="Infernal_Death"]I haven't kept track of the costs but i guess around 300 Euros.[/quote]

I'm at EUR 274 + vat for the parts of 10 filters (no PCB, knobs etc) - without amplifier, housing, PSU. with NE5534 and TL071.

Did you build the whole thing for EUR 300.- ?

 

[Infernal_Death]

I just looked into my parts list and have around 113 Euros (i bought from Reichelt) in parts. Not included are the NE5534, PSU, knobs and silver mica caps.
And those parts aren't more than 180 Euro i think.
Maybe i am missing some parts, the parts list isn't complete.
Like i said i haven't kept track so i can't give you the exact number.

Flo

 

[DrFrankencopter]

Viitalahde, does the unit oscillate at the frequency at which the EQ is set? Is this just the EQ ringing as a result of the switch transient? If you change the frequency switch does the same thing occur? Does the oscillation change in frequency?

One problem with a high Q filter is that it has low damping, and will want to ring....maybe your Q goes a little too high, and is on the edge of being truly resonant (does it ever decay to a point where the ringing is not visible?)

Cheers,

Kris

 

[cwatkins]

Huh, mine doesn't seem to do that, I'll have to look at the resistor.
I used 604's, thinking about putting one side on all 5532's, just for comparison purposes.

 

[MikoKensington]

[quote author="Viitalahde"]What a nice way to spend your friday. :evil:[/quote]

Better than a good day of school.

 

[mik]

VERY VERY GOOD JOB CHUMP! :sam: :sam: :sam: :sam: :sam:

 

[radiance]

[quote author="Viitalahde"] - and that's why the potentionmeter/IC -Sontecs people have built don't oscillate......

[/quote]

Can you explain this for me? I don't understand why you mention potentiometers. Does the oscilation has something to do with rotary switches?

Good troubleshooting work BTW. It must have feld good when you nailed it..

 

[radiance]

Ah, I see...Thanks!

 

[[silent:arts]]

Great work!
which values did you choose for C22/23?
and: some pics of the finished unit, please :grin:

 

[Steffen]

sitting in internet cafe on the lovely island gomera...

when I had oscillation problems with my
sontec it turned out that I missread the schemo:

I used 330n for c25 istead of 33microfarads

the c25 should be tantalium

have to go to the beach now...

steff :green:

 

[5meo-geo]

hello folks
pardon me if the question is stupid but.........
wouldnt it be more easier to set some simple potentiometer for friquensy controll instead of 24 way switch and 24 different resistors????
it can safe alot of unnesesary work and waste of money.....
also friquency range will be much wider than 24 static friquencies

 

[gyraf]

Yes, but it would need to be a very-precise and quite uncommon type potentiometer.

Much harder to find than the simple switch.

Jakob E.

 

[Infernal_Death]

Yes in general you are right. And i used simple pots for my sontec controls. But i believe that Jaakko uses his Sontec for mastering and there you want to be able to control both sides as equal as possible. It's much easier to have stepped controls and match both channels than with pots.
Also you can use 1% tolerance resistors where common pots have much higher tolerance.

You also see this with many commercial units where there are sometimes mastering versions with stepped controls (which cost more).

It really depends on what you want to do with the gear.

Flo

 

[5meo-geo]

[quote author="Infernal_Death"].... and there you want to be able to control both sides as equal as possible. It's much easier to have stepped controls and match both channels than with pots.
Also you can use 1% tolerance resistors where common pots have much higher tolerance.

Flo[/quote]


well that can be solved with simply using double pot i asume
well the reason im asking that is cose i want t build this unit for like 3 band eq but not for mastering pruposal... mostly live preformance and 'ruff' mixing (by ruff i mean its still have to be good but not mastering level)

well i asume i can roll this project now also :grin:
10x for help

 

[Infernal_Death]

[quote author="5meo-geo"]
well that can be solved with simply using double pot i asume
[/quote]

Yes but like Jakob said this would require a very precise pot so both of the tracks would have to be matched. I guess this makes such a pot even more expensive then a 24 rotary switch with some cheap resistors soldered to it.
And a stereo pot would defeat the possibility to be able to use both channels individually if you want to.

Flo