I would like to build a Nap 140 clone kit, but there are few versions: blue pcb NAP140C from Tub***unter, other designed pcb from Gig**ork, or NCC200 ? Does anyone can help me to choose the best between theses kit ? Which better power transistors (sanken 2SC2922, tosh (fake ?) 2SC5200(o) supplied with the kit) gives the better sound quality ?
Kind regards from France.
Kind regards from France.
Re: 2.2K/47pF parallel with 27K
Hi,
I did not try it and I really don't know.
But the person who design NCC2000 believes this work well with the component that he choose. Your milage may vary.
Also tuning has a limit. It depending on the weak link in your entire system. It could be the speaker, CD player, room acoustic.... (plus your ear)
If you really want me to guess, I think I can not tell the difference with the system I have. Again, it is a guess.
Regards,
Lou
Hi,
I did not try it and I really don't know.
But the person who design NCC2000 believes this work well with the component that he choose. Your milage may vary.
Also tuning has a limit. It depending on the weak link in your entire system. It could be the speaker, CD player, room acoustic.... (plus your ear)
If you really want me to guess, I think I can not tell the difference with the system I have. Again, it is a guess.
Regards,
Lou
One or two transformers?
Thanks Lou.
Speakers are Magneplanar MG 12, 86db.
I am considering buying a bigger enclosure for making me able to use two transformers instead of one in this dual mono.
Thus I would have 400VA 27VA+27VA (neutrals centertapped) per channel. Would this be over the top for the NAP-140, and would I be OK with just one? I have both transformers already.
Jan
Thanks Lou.
Speakers are Magneplanar MG 12, 86db.
I am considering buying a bigger enclosure for making me able to use two transformers instead of one in this dual mono.
Thus I would have 400VA 27VA+27VA (neutrals centertapped) per channel. Would this be over the top for the NAP-140, and would I be OK with just one? I have both transformers already.
Jan
Two transformer for NAP-140
Hi Jan,
Two transformers are always better than one. The question is whether you can tell the difference.
No transformer has 100% efficiency. When transformer under some load, heat will build up in the coil (cupper wire expand and vibrate at 60/120 Hz) and further reduce the efficiency and creating noise. (even within the specification).
So transformer performer better at lighter load.
However, NAP140 requires very low idle current, unless you crank up the volume all the time, two transformer may not help. It definately won't hurt though.
I will start with two since you already have both.
You do need two set of huge decoupling cap and bridge diode. That is more important than 2 transformers.
Lou
Hi Jan,
Two transformers are always better than one. The question is whether you can tell the difference.
No transformer has 100% efficiency. When transformer under some load, heat will build up in the coil (cupper wire expand and vibrate at 60/120 Hz) and further reduce the efficiency and creating noise. (even within the specification).
So transformer performer better at lighter load.
However, NAP140 requires very low idle current, unless you crank up the volume all the time, two transformer may not help. It definately won't hurt though.
I will start with two since you already have both.
You do need two set of huge decoupling cap and bridge diode. That is more important than 2 transformers.
Lou
Hello
I use 2x30VAC 430VA transformer and 4x50 000uF Mepco capacitor .
Together for both chanel .
I have two transformer the same but better if the 4 capacitor are together connected by 0.47R resistor .
The PS voltage depend what type of transistors are you using for LTP .
BC550C max rating 45V .
I use BC546B that has higher voltage rating ..The rest of the transistors can take +/-50VDC PS .But only with 8 Ohms speakers .
With 4 Ohms speakers max +/-40V PS .
If you really want to improve the sound please drive the driver stage with separate regulated power supply
The Avondale NCC200
http://www.stardi.com/high-end-audio-power-amplifier-ncc200-class-ab/
The new NCC200 use BC546for LTP .If you can buy Wima 4.7uF 5mm pitch use two of that better than bipolar .I know I used Black G 10uF non polar and the Wima is much better .
I hope these help .
Greets
Attachments
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This US Ebay seller has those Wima MKS2-XL in 10uf.
I've seen many replacing the ceramic caps with polystyrenes (styroflex).
Why? How does it affect stability and sound?
Jan
I've seen many replacing the ceramic caps with polystyrenes (styroflex).
Why? How does it affect stability and sound?
Jan
Hello
Some ceramic caps has high distortion , even sometimes better polystyrenes than dipped silver mica !
Polystyrenes has softer sound , you have to use the same value for stability !
Sometimes even Poly Prop . not good enough ..
I like Poly Prop caps .
NCC200 serous kit , very well tested !
Greets
Some ceramic caps has high distortion , even sometimes better polystyrenes than dipped silver mica !
Polystyrenes has softer sound , you have to use the same value for stability !
Sometimes even Poly Prop . not good enough ..
I like Poly Prop caps .
NCC200 serous kit , very well tested !
Greets
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10uF Cap
Hi,
I think the 10uF and 24K resister are high pass filter. The cut off frequency is 1/(2 * pi *10e-6 * 24K) = 0.66Hz. While the 220pF and 2.7K is for low pass filter. The cut off frequency is 1 / (2 * pi * 220E-12 * 2700) = 267Khz.
So if you can not find 10uF high quality capacitor, using lower value should be fine, I think.
Lou
Hi,
I think the 10uF and 24K resister are high pass filter. The cut off frequency is 1/(2 * pi *10e-6 * 24K) = 0.66Hz. While the 220pF and 2.7K is for low pass filter. The cut off frequency is 1 / (2 * pi * 220E-12 * 2700) = 267Khz.
So if you can not find 10uF high quality capacitor, using lower value should be fine, I think.
Lou
Hi Lou,
Thanks for the taking the time to answer and sharing. Yes, understood
sound quality is hard to say good or bad.
In the past, I built the my ref C type gainclone. I used it with the maggie
MMG's I had at the time which are 86dB. It did not sound good at all, just
harsh and bright. tried removing the coupling caps, different types,etc...
I sold it and the buyer said it sounded just wonderful with his speakers.
My simple logic is with speakers around 86dB, maybe it is not wise
to build class AB amps unless they can put out quite some power.
Maybe the NAP140's 70w output might suffice. I really don't know until
I try as you mentioned
I do like the sound of the aleph amp I built and currently use but the
idle power is just a killer.
Parts list Needed...
I bought the 140 boards from Jim's Audio and received the schematic but no parts list. Does anybody have a parts list with resistor wattage and cap voltage? My power supply will be 40V or less. I'd like to order from Mouser in case you already have Mouser part numbers. Thx.
I bought the 140 boards from Jim's Audio and received the schematic but no parts list. Does anybody have a parts list with resistor wattage and cap voltage? My power supply will be 40V or less. I'd like to order from Mouser in case you already have Mouser part numbers. Thx.
This kit comes with 100uf/16v caps at C3 and C5.
However the supplied printed circuit shows 47uf/50v caps at those positions.
Looks like they shipped it with 47uf at an earlier stage, but didn't update the printout.
I've also seen other circuits having 68uf there.
I guess you would be OK with 47uf, but I wonder what the consequences of using lower values would be for this amp...?
Thanks.
However the supplied printed circuit shows 47uf/50v caps at those positions.
Looks like they shipped it with 47uf at an earlier stage, but didn't update the printout.
I've also seen other circuits having 68uf there.
I guess you would be OK with 47uf, but I wonder what the consequences of using lower values would be for this amp...?
Thanks.
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DC offset
Hi, I built a pair of these NCC200 style clones (140-H) after building the other version (140-C). I only replaced the BC550 small transistors with BC546, the rest is as supplied with the kit (output is toshiba 2sc5200) . Dual mono psu with 30 volt secondaries (43v after rectification, too high?) They sound very nice but I measure 66-70 mv offset on both boards, exactly the same. Isn't this too high? Had 25-30 mv from the other kit (different components and output transistors). Any thoughts?
Hi, I built a pair of these NCC200 style clones (140-H) after building the other version (140-C). I only replaced the BC550 small transistors with BC546, the rest is as supplied with the kit (output is toshiba 2sc5200) . Dual mono psu with 30 volt secondaries (43v after rectification, too high?) They sound very nice but I measure 66-70 mv offset on both boards, exactly the same. Isn't this too high? Had 25-30 mv from the other kit (different components and output transistors). Any thoughts?
47uF vs 100uF for NAP140
Hi,
The 47uF next to 1K will affect the gain of the amplifier.
In short, at higher frequency, the gain is (27+1)/1 = 28.
at lower frequency, the gain will be (27+1+x)/(1+x) < 28 where "x" is the impedance due to 47uF or 100uF.
In theory, higher capacitance value results in better frequency response. However, more bass does not necessary means better bass unless you have a perfect huge decoupling capacitor and perfect woofer. It is up to you to choose the right value. I believe Naim was using 47uF.
Why don't you just use whatever come with the kits then adjust the value later on as part of the tuning procedure ?
Lou
Hi,
The 47uF next to 1K will affect the gain of the amplifier.
In short, at higher frequency, the gain is (27+1)/1 = 28.
at lower frequency, the gain will be (27+1+x)/(1+x) < 28 where "x" is the impedance due to 47uF or 100uF.
In theory, higher capacitance value results in better frequency response. However, more bass does not necessary means better bass unless you have a perfect huge decoupling capacitor and perfect woofer. It is up to you to choose the right value. I believe Naim was using 47uF.
Why don't you just use whatever come with the kits then adjust the value later on as part of the tuning procedure ?
Lou
This kit comes with 100uf/16v caps at C3 and C5.
However the supplied printed circuit shows 47uf/50v caps at those positions.
Looks like they shipped it with 47uf at an earlier stage, but didn't update the printout.
I've also seen other circuits having 68uf there.
I guess you would be OK with 47uf, but I wonder what the consequences of using lower values would be for this amp...?
Thanks.
Hello
The 100uF 16V is the input capacitor ?
If yes it is already way to high.
I agree with kclusa@yahoo.co , test your amplifier with the parts you got it .
If you think there is a room for improvement try it do after .
Usually I com pare one side to another .
Always leave one side the orig. set up ! When you are satisfied after you can adjust the another side to !
Greets
The 100uF 16V is the input capacitor ?
If yes it is already way to high.
I agree with kclusa@yahoo.co , test your amplifier with the parts you got it .
If you think there is a room for improvement try it do after .
Usually I com pare one side to another .
Always leave one side the orig. set up ! When you are satisfied after you can adjust the another side to !
Greets
Thanks both of you.
I'll start out with the 100uf values that came with the kit.
This kit comes with Nichicon Muse FW 220uf/50V and Nichicon Muse FX 100uf/16v. However, I will most likely replace those with either Nichicon's fineste (KZ) or Elma Silmic II.
Not that I've ever heard 'superior' types, but since I prefer to keep replacements after launch to a minimum I will probably drop those KZ or Silmics in to begin with...
Also I've ordered Styroflex to replace all the ceramics, and I will order some Yageo or Holco resistors to replace a few resistors in the signal path, as per Avondale's recommendation for NC220.
My present amp is a LM3875 Gainclone with fairly good parts, and this NAP clone is supposed to replace the GC. Hope it'll be worth it, otherwise I'll consider HPA-nxV200se modules from Holton Precision Audio.
Jan
I'll start out with the 100uf values that came with the kit.
This kit comes with Nichicon Muse FW 220uf/50V and Nichicon Muse FX 100uf/16v. However, I will most likely replace those with either Nichicon's fineste (KZ) or Elma Silmic II.
Not that I've ever heard 'superior' types, but since I prefer to keep replacements after launch to a minimum I will probably drop those KZ or Silmics in to begin with...
Also I've ordered Styroflex to replace all the ceramics, and I will order some Yageo or Holco resistors to replace a few resistors in the signal path, as per Avondale's recommendation for NC220.
My present amp is a LM3875 Gainclone with fairly good parts, and this NAP clone is supposed to replace the GC. Hope it'll be worth it, otherwise I'll consider HPA-nxV200se modules from Holton Precision Audio.
Jan
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Nichicon KZ and Silmic II
Hello,
Just want to comment on these two capacitors.
Particular for Silmic II, it requires very long period of run-in time. Need 2-3 weeks of running before any conclusion. The sound will transition during that period.
Lou
Hello,
Just want to comment on these two capacitors.
Particular for Silmic II, it requires very long period of run-in time. Need 2-3 weeks of running before any conclusion. The sound will transition during that period.
Lou