Salas hotrodded blue DCB1 build

Thank you AndrewT

I have some teflon coated 20 gauge and 24 gauge solid core. The 24 gauge has thinner insulation,but is rectangular, so harder to twist. ( yes, boutique fancy pants stuff.)

I'd think that parasitic capacitance would be irrelevant when hooking up a capacitor.... though I am probably missing something.

what are the other two factors?
 
Given the implementation, using uninsulated wire is not a great idea.... the DCB1 circuit board sits on top of a 3" tall chassis, which contains the transformer, volume control and RCA. The wire from the 0.22uF caps has to go over the PCB and through a chassis penetration. The hole is shrouded with a rubber grommet.

A pair of teflon coated wires may work as well, especially given that the capacitance is 0.22uF. I can try enamelled copper wire as well, as I have a local source -- or one teflon and one enamelled copper... At least it will be a good place to use up the bit of 20 awg teflon coated silver wire I have, which is reportedly too thick for line level signal carrying.

Will want to allow the FT-3 cap to break-in first. Changes will happen next week.
 
This is how mine are temporarily attached. The wire is 2.5mm solid copper wire from a power cable.

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Is the inductance an issue due to the length of the wire alone? In my world, temporary things have a habit of becoming permanent, thus the "solution" of the longer wire run. The run is about 6" in one direction.

What sonic problems would occur due to the inductance? Echo perhaps?
 
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diyAudio Chief Moderator
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6 inch is much, negates any benefit of a better cap and brings an issue: Tank resonance. If it declares itself as new found echo tail in some notes I don't know in this build, but its about ringing in some high frequency. I would expect the perspective to flatten out in depth and the treble to become bit pinched also.
 
What is the purpose off thoose caps ? A zobel just like them in Riaa ? I use 3 uf Mkt from a Samsung Plasma Tv. I have shorted the 1 ohm resistors. Is that very wrong ? Just listened to it for few minutes. and first impression was fantastic. The dac we used would not lock signal from Cd.

The Tv did not survive a earth crack some years ago. A week after it did not work .
 
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It's fugly (as ZM said)

Is there any spesific reason to use those caps? I think that a good appearance is also one of build consideration, not to forget safety avoiding moving parts that may cause shorts. maybe you can try with smaller cap like auricap,claritycap,solen etc. Or lower voltage pio if using pio is a must
 
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Its they are the cheapest Teflon, but if they don't fit its a problem. I would not use more than an inch extensions. FT-2 are smaller and there are many good ones to choose from in various brands that fit better as you said if FT-2 can not be found at 0.22uF at least.
 
Given the implementation, using uninsulated wire is not a great idea....
invalid critcism.
It is easy to slip the short twisted interconnect inside an insulating sleeve.
The di-electric constant of the sleeve has almost no effect on the cable capacitance and cable parameters.
The single layer of teflon dominates the cable parameters.

The only reason I don't use two enameled wires is that the insulation is unknown and thus the parameters are unknown.
But probably worth an experiment or ten, since I have both 0.3mm and 0.4mm diameter enameled copper wire, as well as 0.6mm and thicker for transformer work.

I have experimented with twisted pairs and star Quad using cat5e wire.
These have been so successful that I have adopted them as interconnects in many parts of my systems.
 
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Its they are the cheapest Teflon, but if they don't fit its a problem. I would not use more than an inch extensions. FT-2 are smaller and there are many good ones to choose from in various brands that fit better as you said if FT-2 can not be found at 0.22uF at least.

Can I use a smaller bypass cap at the circuit board with the longer leads?

I did not want to have to go for the spendy teflon stuff... Vcap TFTF at that size is $100 each. Clarity MR is $32, but not teflon. These Russian FT-3 teflons were just $8 each.

I have some Relcap RTE at 5.6 nF....