I could use just the F4 and drop the voltage gain to zero ( lol ) I have no doubt this thing will drive it fine. My jet boz does. right now I set the pot at halfway point and use remote control on CD player. Your 6v6 pre and the F4 are a great match
You have better hand on the pot and even better background details with this system gain structure I suppose?
I am sure it is dcg3 is a wonderful preamplifier,and i have listened a lot!i build another one for the my second system...
I examined the 2CP-2511 TKD 20k model. It measures 18k across and has 4.5k Zo at the 1/2 signal division point. Derived from output signal level drop when applying known loads.
For all intents and purposes its nominal value should be chosen for replacing same nominal value series pots. Because a series has max Zo a quarter of its Zin.
A series would not max out anywhere else than at the 1/2 division point. The TKD Zo also shows 6.3k at 1/4 and 4k at 3/4 division. Its an own kind of pot. But the Zo range is compatible enough.
For all intents and purposes its nominal value should be chosen for replacing same nominal value series pots. Because a series has max Zo a quarter of its Zin.
A series would not max out anywhere else than at the 1/2 division point. The TKD Zo also shows 6.3k at 1/4 and 4k at 3/4 division. Its an own kind of pot. But the Zo range is compatible enough.
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So if we have access to all the TKD pots, which one should we buy? Now thinking about changing my Alps blue pot.
If only the 10k TKD is available (and if you don't like the tonal balance with it) add 2.2k good quality resistor in series from wiper (pin 2) to the DCG3's input.
I have TKD pots on my balanced DCG3 unit..... much better SQ than with previous ALPS blue.
Higher overall definition without a hint of edginess I sometimes find with discrete pots made of metal resistors... 🙂
Higher overall definition without a hint of edginess I sometimes find with discrete pots made of metal resistors... 🙂
What gauge size is prefered to use for secondaries feeding the DCSTB? Im using two 50va trannies.
The terminal block screw connectors have a wire range of 14-22 AWG I think. Not critical to choose a specific gauge in that range, its not a high power situation.
Yes, the terminal block's screw should grab 20AWG well. Yes twist because its stepped down AC at mains frequency they carry, thus you are making their electromagnetic field emission area much smaller in that way.
Salas DCG3 preamp (line & headphone)
Mu Metal sheets installation helped to reduce some small grass in low frequency region on my DCG3, but didn’t kill the targeted 60Hz spike with its harmonics.
I chased down all over for several evenings and ….. I did find out that this is all in my analyzer setup cables. Salas mentioned that once when we discussed cheap RCA to TRS adapters.
Tried several other homemade cables with these cheap ¼ TRS adapters with mostly same results.
Some are more noisy than the others, but all have same picks at the same exact points as on my image during loop test.
I tried to use XLR input on Focusrite and it’s got even worth for that noise.
Since spikes frequency points locations, amplitude and shape are exactly same as during my DCG3 test, then would be correct to say that my DCG3 is totally clean and these spikes are the artifact from my spectrum FFT setup.
I ordered bulk Mogami MG-2893 two sets with prof assembly for rec-studios. One with ¼ TRS-to-RCA, but the second one is ordered by mistake with RCA-to-XLR.
I’ll probably going to remove XLR and will solder some decent quality ¼ TRS. Lets see if these will resolve my issue for future FFT needs.
Mu Metal sheets installation helped to reduce some small grass in low frequency region on my DCG3, but didn’t kill the targeted 60Hz spike with its harmonics.
I chased down all over for several evenings and ….. I did find out that this is all in my analyzer setup cables. Salas mentioned that once when we discussed cheap RCA to TRS adapters.
Tried several other homemade cables with these cheap ¼ TRS adapters with mostly same results.
Some are more noisy than the others, but all have same picks at the same exact points as on my image during loop test.
I tried to use XLR input on Focusrite and it’s got even worth for that noise.
Since spikes frequency points locations, amplitude and shape are exactly same as during my DCG3 test, then would be correct to say that my DCG3 is totally clean and these spikes are the artifact from my spectrum FFT setup.
I ordered bulk Mogami MG-2893 two sets with prof assembly for rec-studios. One with ¼ TRS-to-RCA, but the second one is ordered by mistake with RCA-to-XLR.
I’ll probably going to remove XLR and will solder some decent quality ¼ TRS. Lets see if these will resolve my issue for future FFT needs.
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Salas, got my 10k TKD pot installed. Used a 3.01k resistor, didn’t have any 2.2k. Overall impressions? I once described this preamp as a “ window on the world”, well somebody just found the windex ! Blacker backgrounds, smoother, but the bass, clean, airy, articulate and musical all the way down to dc. THE best bass I have ever heard in my 67 years on the planet. My hat is off to you Salas ! Bravo ! I have different bc327-40 to try next, will check back in later. Mark