Hello, I am new to the forum. I would like to upgrade my amplifier nad c316bee . An engineer advised me to changing the input buffer input transistors from NPN to a J-Fet (J112 or 2SK246). Is there a noticeable difference? Where is it located on the board?
Please help.
Hi Omair,
We'd need a schematic first to advise on whether replacing the component is possible or advised.
Also, "NPN" is the gender of the device. NPN is a N-Channel transistor. The J112 to asked about a is N-Channel transistor. I suspect you are asking about replacing a BJT N-Channel device with a JFET N-Channel device. We'd need to see a schematic to confirm.
We'd need a schematic first to advise on whether replacing the component is possible or advised.
Also, "NPN" is the gender of the device. NPN is a N-Channel transistor. The J112 to asked about a is N-Channel transistor. I suspect you are asking about replacing a BJT N-Channel device with a JFET N-Channel device. We'd need to see a schematic to confirm.
Also, you probably won't get a lot of attention by posting this in the introductions. This should probably be in the Solid State Amplifier forum or maybe the Analog Line Level forum. I'm not familiar with this device, so not clear if its a power amp or a pre-amp. You can ask one of the mods to move it.
Hi, Brian, who advised me, is an engineer at a high-end equipment manufacturing company, but he didn't specify where they were located. I don't understand much about electronics.
This is a rather complex circuit and would not be amenable to substituting a different type of device,
or even just a different BJT, without careful consideration and redesign. I would recommend against it.
or even just a different BJT, without careful consideration and redesign. I would recommend against it.
The schematic is still needed. This will identify the reference number of the device to be replaced. This can then be identified on the PCB.
FYI, I have the 320BEE. It has 2SK369 which is JFET in the part list. It is not on the main board, it is on a mini board which "stands up" on the mainboard.. image added here.
The 320 worked great for 20 years before it started blowing fusable resistors and fluctuating volume. I fixed it a couple of times before scraping the mainboard and saved the chassis for another project. I installed DR3886 modules.
Opinions vary but I say let vintage amps rest in peace.
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Hi Fubar
Did you know that I have more than one high-end amp, and I did not like the sound of any amp except this one
Did you know that I have more than one high-end amp, and I did not like the sound of any amp except this one
I ordered nichicon audio capacitors to upgrade it and I don't know if it will make a difference.
Maybe because vintage amps have tone controls which seem to be rare on newer gear. Otherwise, why upgrade something that you already prefer.
Power supply caps can be tested. Replace ones that have become "dry".
Yes, the main capacitors are chemi-Con khm 10000uf 2. The complete set of capacitors costs $140.
NAD was a low quality brand with tricky circuits.
Think about replacing main amp with a new plate amp, more reliable and about same price as a capacitor set. Use the same chassis etc.
Pre amp can be byepassed with computer source, direct to plate amp, just buy one rated for higher than PSU volts on the existing amp, I expect $20 or so here locally for a 1943 / 5200 plate amp, or a 80N80 based 'Mosfet' unit, that is quite enough for most home use.
Tone control is same as equalizer found in most software players, I use my computer as music store, use mostly Winamp, for the past 20 odd years.
My cassettes are in storage for a long time, and belts etc. are difficult to find.
Think about it.
Think about replacing main amp with a new plate amp, more reliable and about same price as a capacitor set. Use the same chassis etc.
Pre amp can be byepassed with computer source, direct to plate amp, just buy one rated for higher than PSU volts on the existing amp, I expect $20 or so here locally for a 1943 / 5200 plate amp, or a 80N80 based 'Mosfet' unit, that is quite enough for most home use.
Tone control is same as equalizer found in most software players, I use my computer as music store, use mostly Winamp, for the past 20 odd years.
My cassettes are in storage for a long time, and belts etc. are difficult to find.
Think about it.