ken:
caveat: i have not listened to either of these preamps.
in some of my own experiments, i have heard differences when listening to different types of music: say for example small group acoustic jazz (maybe a trio) and large symphony orchestra. try that and see if you notice anything. well recorded solo piano may be useful also.
since these are both well done preamps, i wouldn't expect a difference that jumps up and slaps you in the face necessarily. do some extended listening.
btw, assuming the rest of your gear is "good enough" to not confuse things ...
mlloyd1
caveat: i have not listened to either of these preamps.
in some of my own experiments, i have heard differences when listening to different types of music: say for example small group acoustic jazz (maybe a trio) and large symphony orchestra. try that and see if you notice anything. well recorded solo piano may be useful also.
since these are both well done preamps, i wouldn't expect a difference that jumps up and slaps you in the face necessarily. do some extended listening.
btw, assuming the rest of your gear is "good enough" to not confuse things ...
mlloyd1
ken.berg said:
Just for the record, next Saturday we have comparative listening test with Parasound Halo JC-2 .. 😉
PMA said:
Thanks, Pavel.
I will do so. I was hoping to hear the basis of the 'magic' that many rave about, but I haven't been able to focus in on what it may be.
(most of my musical focus has been small combo jazz & pop, female vocals, and some larger concert music - from SACD and phono, but I will admit that I may not have fully had the original unit in my subconscious before trying the mod.)
Let us know how the JC2 comparison goes.
- Ken
Ken,
I guess this preamp would not differ from "openloop" discrete designs that much. In case you have a possibility to compare with opamp based preamp, try it and let me know. I can hear quite big differences here.
Regards,
Pavel
I guess this preamp would not differ from "openloop" discrete designs that much. In case you have a possibility to compare with opamp based preamp, try it and let me know. I can hear quite big differences here.
Regards,
Pavel
For those who might be interested, several news about PSU - photo and SNR added:
http://web.telecom.cz/macura/dispre2_en.htm
http://web.telecom.cz/macura/dispre2_en.htm
PMA:
that's very impressive performance with the new psu.
and not even using the latest, greatest op amp!
😉
mlloyd1
that's very impressive performance with the new psu.
and not even using the latest, greatest op amp!
😉
mlloyd1
PMA said:
I should add it depends on wiring as well. It is very, very easy to make a mistake.
.... and I have not used any teflon yet 😉
.... and I have not used any teflon yet 😉
PMA,
I see you are taking a break from making PCBs. Please keep us posted as to when you will be producing PCBs again. I am quite interested. I am anxious to try a non op-amp preamp.
Thanks
I see you are taking a break from making PCBs. Please keep us posted as to when you will be producing PCBs again. I am quite interested. I am anxious to try a non op-amp preamp.
Thanks
So, we listened to Halo JC-2 and Dispre II today. It was a very pleasant day with very good components 🙂, good sound and good music.
Taking into account that JC-2 and Dispre II use very different transistors (JFET, MOSFET vs. BJT), have different input and output impedance, the results are MORE than interesting.
Both preamps sounded very similar. There were no bigger differences in their sound. Maybe, maybe Parasound had a little bit more "air", and Dispre was a little bit cleaner. We were very pleased with listening to both, and there was no winner, just music 🙂.
Taking into account that JC-2 and Dispre II use very different transistors (JFET, MOSFET vs. BJT), have different input and output impedance, the results are MORE than interesting.
Both preamps sounded very similar. There were no bigger differences in their sound. Maybe, maybe Parasound had a little bit more "air", and Dispre was a little bit cleaner. We were very pleased with listening to both, and there was no winner, just music 🙂.
Attachments
PMA said:
Soooo... Two amps built in completely different technologies, twenty years apart, sound the same, while of course, teflon insulated silver wiring, and other similar gadgets, like copper foil capacitors, Bybee devices, etc... have a clearly audible impact.
In fact I am pretty sure they sound the same, and so are other 1259 competent designs, based on discretes or opamps. What really makes a difference is the marketing engine you are trying so hard to tap into.
Syn08, you don't even know what preamps that PMA is comparing. I'm surprised by your lack of knowledge, and still bothering to comment.
The JC-2 is very similar to the Dispre preamp in many ways.
Both use a complementary differential input topology, medium feedback, and class A complementary follower output stage. The only outstanding difference is highly degenerated bipolar (Dispre) vs all fet (JC-2).
I am not surprised that they sound similar, because I trust that PMA has also followed through with quality caps, wire, layout.
It is the CTC Blowtorch, designed by the same 3 designers, that uses silver wire, open loop operation, etc. and costs 4 times as much, with 1/2 the features of the JC-2.
The CTC Blowtorch does sound slightly better than the JC-2 in informed listening comparisons, by people who have lived with both. I am not surprised.
I wish to congratulate PMA for his professionalism in this comparison. Many here would be crowing about their personal design and how much better it is. Professionals keep their own personal bias in check, and respect other designers efforts, even if they take a somewhat different approach.
The JC-2 is very similar to the Dispre preamp in many ways.
Both use a complementary differential input topology, medium feedback, and class A complementary follower output stage. The only outstanding difference is highly degenerated bipolar (Dispre) vs all fet (JC-2).
I am not surprised that they sound similar, because I trust that PMA has also followed through with quality caps, wire, layout.
It is the CTC Blowtorch, designed by the same 3 designers, that uses silver wire, open loop operation, etc. and costs 4 times as much, with 1/2 the features of the JC-2.
The CTC Blowtorch does sound slightly better than the JC-2 in informed listening comparisons, by people who have lived with both. I am not surprised.
I wish to congratulate PMA for his professionalism in this comparison. Many here would be crowing about their personal design and how much better it is. Professionals keep their own personal bias in check, and respect other designers efforts, even if they take a somewhat different approach.
Well, I am not sure if I understand well. As far as I know, Talema transformers are produced in more countries. It is here in Czechia, near Pilsen, in India, and probably in another countries as well.
I know there is a producer of toroidal transformers in Estonia.
This Talema I have used has primary - to - secondary capacitance of 470pF, if it helps. It is quiet and does not heat.
I know there is a producer of toroidal transformers in Estonia.
This Talema I have used has primary - to - secondary capacitance of 470pF, if it helps. It is quiet and does not heat.
syn08, Parasound Halo JC-2 is not 20 years old design, but about 2 years (2006). There was another JC2, in the seventies.
Though JC-2 and Dispre II sound similar, they do not sound similar as opamp based designs. This is no marketing declaration, marketing is something you seem to be hooked on.
Though JC-2 and Dispre II sound similar, they do not sound similar as opamp based designs. This is no marketing declaration, marketing is something you seem to be hooked on.