miles behind you lot just finished the bias cct version in a semi prototype form 
with a few pm's with Mike...many thanks
SIT's are driving AER MD3's in Oris 250 horns and the Parasound driving BD Design BD15 bass drivers in REF2010 cabs with an Oris 150 horn on the front.
Active crossover by a Trinnov ST2
with a few pm's with Mike...many thanks SIT's are driving AER MD3's in Oris 250 horns and the Parasound driving BD Design BD15 bass drivers in REF2010 cabs with an Oris 150 horn on the front.
Active crossover by a Trinnov ST2
An externally hosted image should be here but it was not working when we last tested it.
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Complex Elegance
Hi all,
My 2SK82 are on the way, several sets, I like to have spares! I think we may be losing sight of the end goal that is maximum musical and hence emotional pleasure from these let's face it, very leading edge or ultra-fi devices and circuits. While My senses tells me that simpler amplifier circuits perform better I think we should not be afraid of more complex surrounding circuitry ie current sources, on the other hand if a simple inductor performs better in the pursuit of our musical goal, and this may well be at the end of the day the best solution then so be it. A lot of what we humans can perceive cannot be measured for now at least so we have to trust our senses.
For my own part I'd prefer an even simpler amplifier circuit ie no input and output capacitors, I'm thinking here of F1, SOZ or Circlotron type circuits with whatever surrounding circuitry is best to maximise our pleasure, balanced circuits potentially offer much more transparency to the input signal when employing these devices.
I don't have much time to spare as my wife is disabled so I'm unable to post very much or even read as many posts as I'd like, but right now in the entire world of hi-fi what other devices or amplifiers offer as much? To my mind this is the most interesting thread, topic, amplifier, device there is, anywhere at any price, full stop! (PASS SIT-1 excluded of course, I'd love to own Papas SIT amps! Sadly I lack the funds)
I'd like to thank Mike for his pioneering work here, clearly this man has not lost sight of our goal.
No input on this thread either theoretical or from direct experience is wasted, it creates new ways of thinking about the various challenges and hence possible solutions, I applaud you all! I don't know when I'll have my own SIT amp built but recent life experiences have taught me to be patient (ish)
Regards RC
Hi all,
My 2SK82 are on the way, several sets, I like to have spares! I think we may be losing sight of the end goal that is maximum musical and hence emotional pleasure from these let's face it, very leading edge or ultra-fi devices and circuits. While My senses tells me that simpler amplifier circuits perform better I think we should not be afraid of more complex surrounding circuitry ie current sources, on the other hand if a simple inductor performs better in the pursuit of our musical goal, and this may well be at the end of the day the best solution then so be it. A lot of what we humans can perceive cannot be measured for now at least so we have to trust our senses.
For my own part I'd prefer an even simpler amplifier circuit ie no input and output capacitors, I'm thinking here of F1, SOZ or Circlotron type circuits with whatever surrounding circuitry is best to maximise our pleasure, balanced circuits potentially offer much more transparency to the input signal when employing these devices.
I don't have much time to spare as my wife is disabled so I'm unable to post very much or even read as many posts as I'd like, but right now in the entire world of hi-fi what other devices or amplifiers offer as much? To my mind this is the most interesting thread, topic, amplifier, device there is, anywhere at any price, full stop! (PASS SIT-1 excluded of course, I'd love to own Papas SIT amps! Sadly I lack the funds)
I'd like to thank Mike for his pioneering work here, clearly this man has not lost sight of our goal.
No input on this thread either theoretical or from direct experience is wasted, it creates new ways of thinking about the various challenges and hence possible solutions, I applaud you all! I don't know when I'll have my own SIT amp built but recent life experiences have taught me to be patient (ish)
Regards RC
nice system Kasumi , if you have negative bias on gate take care to fine tune the setting , with my own horn speaker 1.9amp don't sounds the same then 2amp bias
Thanks
Just monitoring Vds with a digital meter on the front,presume you're referring to Id with 1.9A and 2A,what would this equate to for Vds ?thanks Mike
here is the build on Wigwam
SIT amp project
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nice system Kasumi , if you have negative bias on gate take care to fine tune the setting , with my own horn speaker 1.9amp don't sounds the same then 2amp bias
I got a couple of these off FleaBay for my SIT Monoblocks.
Regards,
Dan
Hi Dan have you got a link ?
I have just ordered some exotic caps to try,daft decision,before I solder them in ????
10uF Jupiter Flat Stacks and some 10k Nichicon KG "Super Through" electrolytics
Currently using 2w Kiwame resistors in the build.
Cheers
Rob
What would be best to monitor Id or Vds with a permanent meter,I currently have a Lascar emv1200 digital voltmeter monitoring Vds on both monos
I have just ordered some exotic caps to try,daft decision,before I solder them in ????
10uF Jupiter Flat Stacks and some 10k Nichicon KG "Super Through" electrolytics
Currently using 2w Kiwame resistors in the build.
Cheers
Rob
What would be best to monitor Id or Vds with a permanent meter,I currently have a Lascar emv1200 digital voltmeter monitoring Vds on both monos
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Of course!
High Quality Round Analog AMP Panel Meter DC 5A | eBay
I'm thinking of the Obligatto Gold Series for the 10uF and the same Nichicon for the 10,000uF.
Regards,
Dan
for the 10uf the clarity cap ESA (250V) is cheap and you can use it on the output too. the quality of the 10000uf is not critical as you bypass them with a 10uf .
also carbon comp for the gate stopper, kiwame 2w is good and small and you can solder it directly on the 2SK82.
don't forget the PS if the CRC is good for the Job , i have found in my system that a CLC ( with the same value for the Caps) sounds faster and even more silent with my 102db speaker..
good building at all
also carbon comp for the gate stopper, kiwame 2w is good and small and you can solder it directly on the 2SK82.
don't forget the PS if the CRC is good for the Job , i have found in my system that a CLC ( with the same value for the Caps) sounds faster and even more silent with my 102db speaker..
good building at all
for the 10uf the clarity cap ESA (250V) is cheap and you can use it on the output too. the quality of the 10000uf is not critical as you bypass them with a 10uf .
also carbon comp for the gate stopper, kiwame 2w is good and small and you can solder it directly on the 2SK82.
don't forget the PS if the CRC is good for the Job , i have found in my system that a CLC ( with the same value for the Caps) sounds faster and even more silent with my 102db speaker..
good building at all
Hi juanitox
Why are you bypassing the 10k with a 10uF ? I'm learning
What size inductor were you using in the CLC ?
Cheers
Rob
hi Kasumi, i'm learning too .. the 10uf bypass on the output cap is to get more open highs than with the electrolyte alone.
for the CLC power supply i use a 10mh hammond choke but Nelson Pass usually use 2mh ones
20$ for a good quality 10uf film Cap is correct when you compare with mundof S/O , VCAP , etc.. and i don't talk of the crazy duelund brand
for the CLC power supply i use a 10mh hammond choke but Nelson Pass usually use 2mh ones
20$ for a good quality 10uf film Cap is correct when you compare with mundof S/O , VCAP , etc.. and i don't talk of the crazy duelund brand
Back from Scotland-sailing....
Hi Michael or the one knowing more than me...
Wondered if I should order 2 pcs of 100 kohm to use instead of the 47 kohm on the gate/earth input? I see NP`s SIT 1 has switchable input 10/100 kohm - to use with passive preamps. My B1-passive may not be able to fully utilize the bandwith of the LÀmp?
Anyone....
Still waiting for my few 1 ohms film-resistors(have some 10 ohms ohmite - but will be too many to paralell)
Regards
Olav
Hi Michael or the one knowing more than me...
Wondered if I should order 2 pcs of 100 kohm to use instead of the 47 kohm on the gate/earth input? I see NP`s SIT 1 has switchable input 10/100 kohm - to use with passive preamps. My B1-passive may not be able to fully utilize the bandwith of the LÀmp?
Anyone....
Still waiting for my few 1 ohms film-resistors(have some 10 ohms ohmite - but will be too many to paralell)
Regards
Olav
B1 certainly won't have any trouble with 47k. However, it is important to remember that the B1 has no gain and that L'Amp has very little gain. So, if your source is an iPod or something with very little output, you may be disappointed. On the other hand if you have really efficeint speakers it may not be an issue. Ideally, an active preamp with low output impedance, capable of 5-6V out (or more) would be nice here.
Hi Olav,
I think Nelson had reasons to skip the 47k from the prototype of SIT-2
the driving of the SITs capacities is better with 1ok, Nelson did the same with the F2J, first the input resistor was 47k too, a compromise between usability for many pres
and bandwidth, now you can see that he implemented even 8k2 in the F2J.
and as Zen Mod said, the 100k you can switch now in the SIT-1 are done with a B1 like (?) buffer.....
so do not buy 2x 100k.... look at your pre output impedance...your B1 can drive the 47k for sure and the 10k also I suppose....but as Mike said yo have not much gain!