When I pipe Darkvoice RCA line out to SS amplifier in order to listen to Sundara, the sound is so anemic and weak. It does not help to crank up volume or increase gain in my SS amplifier (Topping) - it just gets louder with no bass LOL.
But when I pipe Eufonika H5 RCA line out to SS amp, it sounds so impressively powerful to drive Sundara while retaining the awesome tube sound.
Both tube amps are simple OTL amps.
The question is, what would account for this difference...? Obviously some kind of circuit design, but would it be the more powerful capacitors in Eufonika ? Or would it be due to the fact that Eufonika has "input and output stages have separate power supply." ? Whatever the reason, the RCA out from Eufonika is so much more powerful.
Thanks...
But when I pipe Eufonika H5 RCA line out to SS amp, it sounds so impressively powerful to drive Sundara while retaining the awesome tube sound.
Both tube amps are simple OTL amps.
The question is, what would account for this difference...? Obviously some kind of circuit design, but would it be the more powerful capacitors in Eufonika ? Or would it be due to the fact that Eufonika has "input and output stages have separate power supply." ? Whatever the reason, the RCA out from Eufonika is so much more powerful.
Thanks...
Output cap too small.
A detailed explanation needs internal details of the "Darkvoice" (they have multiple models and variants?) and some clue about this "SS amplifier".
A detailed explanation needs internal details of the "Darkvoice" (they have multiple models and variants?) and some clue about this "SS amplifier".
That's what happens when a coupling cap is not large enough for its load impedance.
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The output impedance is important here, so is the input impedance of the power amp. Loading an amp
more then it's designed output impedance will cause distortion and lack of parts of the spectrum.
The above example highlights this, one preamp can cope, the other cannot.
Yes, it's the design that is the cause. It's not a "faulty" design, it's as simple as it's designed for another environment
where tubeamps is generally much easier to drive i.e. have higher impedance.
If the 2K resistors at the line out terminals in the attched schematic are also there in the version of the Darkvoice that TS has, than it does look like a faulty design. The impedance as seen by the 0.47 uF capacitor is lower than 2K (how much lower depends on the input impedance of the amplifier connected to the line out terminals; the 10K resistors at the output terminals for the headphones also play a roll since for ac signal they are parallel to the 2K resistors).
Looking at the graphs of PRR in post # 2, it is no wonder that with these 2K resistors the bass would be lacking.
Looking at the graphs of PRR in post # 2, it is no wonder that with these 2K resistors the bass would be lacking.
Yes, absolutely unnecessary 2K load resistors there are gross, -3dB point around 170Hz.
Guess/hope it´s a typo.
Maybe they were swapped?
By somebody lifting the circuit.
10K as preamp out load might be more reasonable , and 2K at Phone out might be actually there or simply indicate load impedance suggested; not sure about what headphone impedances are most popular nowadays.
Back in the day, 8 ohm and 600 ohm were the standard, then portable Audio (Walkman) introduced 32 ohm to the menu (yes, I know, I am dating myself
) , not sure what the "yung ´uns" prefer today.
Guess/hope it´s a typo.
Maybe they were swapped?
By somebody lifting the circuit.
10K as preamp out load might be more reasonable , and 2K at Phone out might be actually there or simply indicate load impedance suggested; not sure about what headphone impedances are most popular nowadays.
Back in the day, 8 ohm and 600 ohm were the standard, then portable Audio (Walkman) introduced 32 ohm to the menu (yes, I know, I am dating myself
) , not sure what the "yung ´uns" prefer today.Preamp output load resistor is 1M in the photos, 2k is grossly a typo. The explanation is perhaps they're differences in the input impedance, usually 20k, the other one maybe higher (check).
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