Bern,
Those look good.
Can't wait to see the rest
Those look good.
Can't wait to see the rest
1. In the first couple of listening tests I had the sound deteriorate after maybe 20-30 minutes of listening.
I would start getting noisy cracking background and overall sound "quality" would drop a lot.
Were you asking for a technical comparison of circuit topologies? About reviews or opinions on perceived SQ? Suitability for use with particular type of dacs? Cost to build? FFT measurements? Input Z? Something else?How does this I/V compare to the one Jocko posted in 2002?
Yes, all of the above! I've only just glanced at the Sen, but it "looks" similar to Jocko. Similar number of transistors , etc. They are both cathode, correct?Were you asking for a technical comparison of circuit topologies? About reviews or opinions on perceived SQ? Suitability for use with particular type of dacs? Cost to build? FFT measurements? Input Z? Something else?
Yes, apologies -- my bad for having only a cursory glance at your thread. Yes, totally diff. Yours uses FETs, etc.Totally different design and even working principles.
I don't see how they should / could be compared.
Maybe you should at least read the article on the Linear Audio website first to understand how it works.
Cheers,
Patrick
It would be good if someone could create TABLE of the I/V topologies you hint at above, in concordance with their "ideal" DAC topologies .the Cen/Sen suites well DACs with a symmetrical current swing wo. offset current., while the Jocko circuit suites well DACs with an offset current (sinking in the above linked circuit).
For current sourcing DACs with offset current like the popular TI PCM179x series a 'inverted' Jocko utilizing PNPs fits better.
In that case one could not only omit with the biasing current source Q3, but overall current consumption, resp. heat power could be reduced also.
The DAC output would only be connected to the PNP-Emitter (Q2).
Since the offset current is always larger than the peak output current -never reaching, let alone crossing 0mA- the circuit remains biased under all circumstances ... hence the extra current source (Q3) is not required.
Also not required would be the positive supply line, making things even easier.
Yes, as the RBroer thread title clearly states: it is only intended for TDA1543, 1545A [the 8-pin Philips TDAs]. It should be noted that diyparadise.com was able to iterate that orig. design into further refinement in their myriad "mojo" PCBs:the RBroer stage is imho only good for the TDA1543, but not the TDA1541A, due to the voltage levels the I/V input resp.
I also don´t share the optimizm about the folded cascode design.
I'm not I quite get why one would want the added complexity of cascode in an audio i/v stage? TTBOMK, Miller affects very high freqs., and not audio (human ear) bandwidth. Or does cascodting improve buffering, S/N or dynamic range?The other one is [CEN/SEN ??] a totally folded [cascode] amplifier as far as I see.