hi,
i have a question with the input impedance of the preamp and the input cap it is 100nf then 1M resistor to ground then going to the fet transistor 2sk170.
can i chane the cap to 10uf and the resistor to 100k?
why is the 1M resistor there instead of 47-100k?
can somebody explain it to me please?
i have a question with the input impedance of the preamp and the input cap it is 100nf then 1M resistor to ground then going to the fet transistor 2sk170.
can i chane the cap to 10uf and the resistor to 100k?
why is the 1M resistor there instead of 47-100k?
can somebody explain it to me please?
Hi namcir,
The J-FET input is much like a vacuum tube, or valve. It doesn't require a low resistance to ground for bias currents. Therefore they can use a smaller, higher quality capacitor at a higher resistance and not sacrifice bass response.
I'd leave it the way it is. Going to an electrolytic cap is a step backwards in quality. Sounds like it has promise as a good amp.
-Chris
The J-FET input is much like a vacuum tube, or valve. It doesn't require a low resistance to ground for bias currents. Therefore they can use a smaller, higher quality capacitor at a higher resistance and not sacrifice bass response.
I'd leave it the way it is. Going to an electrolytic cap is a step backwards in quality. Sounds like it has promise as a good amp.
-Chris
hi,
thanks marvin, oh yes now i know...
this is a good amp IMHO better than my yamaha amp more detailed and good in midbass.
but i think there are things that can be improved.
for the preamp input cap i'm planning to substitute it with a 10uf mkt not an electrolytic.
i have noticed there are some differences in the sm example in the preamp sm indicates 2sk363 input fet but actually in the unit they used 2sk170. again in amp driver stage sm=2sd669,2sb649
but amp=2sc5171, 2sa1930 and some parts etc.
i dont know why? can somebody explain? is the one i have a new version or an old version?
???
anyone?
thanks marvin, oh yes now i know...
this is a good amp IMHO better than my yamaha amp more detailed and good in midbass.
but i think there are things that can be improved.
for the preamp input cap i'm planning to substitute it with a 10uf mkt not an electrolytic.
i have noticed there are some differences in the sm example in the preamp sm indicates 2sk363 input fet but actually in the unit they used 2sk170. again in amp driver stage sm=2sd669,2sb649
but amp=2sc5171, 2sa1930 and some parts etc.
i dont know why? can somebody explain? is the one i have a new version or an old version?
???anyone?
Hi namcir,
Nothing wrong with the transistor subs. If they matched the 2SK170, it will be very stable. The other transistors simply replace old numbers. What you should be pleased about is that they didn't use the older junk transistors they were famous for doing.
If you must replace the input cap, try 0.47 or 1.0 uF at the most. Leave the input resistance where it is. If anything, I would replace the input cap with better (I haven't seen it yet - so what is better?) and the same value. Possibly 0.22 uF at the most.
-Chris
Nothing wrong with the transistor subs. If they matched the 2SK170, it will be very stable. The other transistors simply replace old numbers. What you should be pleased about is that they didn't use the older junk transistors they were famous for doing.
If you must replace the input cap, try 0.47 or 1.0 uF at the most. Leave the input resistance where it is. If anything, I would replace the input cap with better (I haven't seen it yet - so what is better?) and the same value. Possibly 0.22 uF at the most.
Calm down there sparky!
-Chris
hi martian,
thanks...i like your avatar too...
are we in mars? oh ho boy i feel like in this thread its only you and me and no other living persons want to participate. (as usual) where's porky?
btw i have ordered some parts to farnell thru their local supplier. maybe it will take one week, will begin modding after parts arrive.
maybe nobody here has this amp nad c352. oh yes this is a diy community i forgot most people will assemble thier own gig...
its just me and my friend MARTIAN!
thanks...i like your avatar too...
are we in mars? oh ho boy i feel like in this thread its only you and me and no other living persons
want to participate. (as usual) where's porky?btw i have ordered some parts to farnell thru their local supplier. maybe it will take one week, will begin modding after parts arrive.
maybe nobody here has this amp nad c352. oh yes this is a diy community i forgot most people will assemble thier own gig...
its just me and my friend MARTIAN!
Hi namcir,
Well, we have all kinds of people here. Some only want to repair their unit. Others may want to push a commercial unit further in performance. Then there are those who want to build a pretested circuit, possibly with a PCB board purchase. Then you have the die hard DIYer who designs everything from teh ground up. This is where the fun really starts.
I must admit to being in all categories depending on what the item is and the mood I'm in.
No, we are definitely on earth. Enjoy!
-Chris
Well, we have all kinds of people here. Some only want to repair their unit. Others may want to push a commercial unit further in performance. Then there are those who want to build a pretested circuit, possibly with a PCB board purchase. Then you have the die hard DIYer who designs everything from teh ground up. This is where the fun really starts.
I must admit to being in all categories depending on what the item is and the mood I'm in.
No, we are definitely on earth. Enjoy!
-Chris
NAD c352
Hi all ,
Need a service manual for NAD c352 amplifier .
can sum1 mail it to me please .
hargunaneyharesh@hotmail.com
Hi all ,
Need a service manual for NAD c352 amplifier .
can sum1 mail it to me please .
hargunaneyharesh@hotmail.com
service manuals
ebbe is a very kind person
i remember a year ago i ordered & paid a service manual for my yamaha amp, my nad amp, etc. to a person whose place is in india whose name is chiragshia.
after i send him the money he told me to wait...& wait, i waited for 1 day, then another day...a week, then a month he never replied to any of my e-mails that person is a fake! a fraud he is from india now i hate indian i never trust them anymore. i have cursed that person hopes he is still alive and suffering! some guys asked for a service manual then sell them for profits.
sorry for my anger but after paying my hard earned money & trusting someone to send you the manual...oh very frustrating godwilling he is alive and suffering!
ebbe is a very kind person
i remember a year ago i ordered & paid a service manual for my yamaha amp, my nad amp, etc. to a person whose place is in india whose name is chiragshia.
after i send him the money he told me to wait...& wait, i waited for 1 day, then another day...a week, then a month he never replied to any of my e-mails that person is a fake! a fraud he is from india now i hate indian i never trust them anymore. i have cursed that person hopes he is still alive and suffering! some guys asked for a service manual then sell them for profits.
sorry for my anger but after paying my hard earned money & trusting someone to send you the manual...oh very frustrating godwilling he is alive and suffering!
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