No experience with NCore or the newer class D stuff.
My F5 replaced a DTA-100a (I paid ~$69 for) used as a placeholder amp while I built the F5. The 5687 Aikido into the cheap DTA sounded nice and musical, and better than my old NAD integrated, especially on voices and voice harmonies, but the F5 absolutely smokes it.
The first difference, among many, that I noticed once the F5 was warmed up was how the F5 handles multi-layered passages. I heard lots of new things on recordings I thought I was very familiar with. Soundstage depth, room reverb and note decay also stand out on good recordings, but I'm certain that's a Class A thing that I had just never experienced before.
The class D (or Tripath?) of the DTA couldn't reveal all of the layers at once, and got mushy pretty quickly. It's been assigned to drive my garage system now.
F5 = mind, blown, for this guy.
My F5 replaced a DTA-100a (I paid ~$69 for) used as a placeholder amp while I built the F5. The 5687 Aikido into the cheap DTA sounded nice and musical, and better than my old NAD integrated, especially on voices and voice harmonies, but the F5 absolutely smokes it.
The first difference, among many, that I noticed once the F5 was warmed up was how the F5 handles multi-layered passages. I heard lots of new things on recordings I thought I was very familiar with. Soundstage depth, room reverb and note decay also stand out on good recordings, but I'm certain that's a Class A thing that I had just never experienced before.
The class D (or Tripath?) of the DTA couldn't reveal all of the layers at once, and got mushy pretty quickly. It's been assigned to drive my garage system now.
F5 = mind, blown, for this guy.
Pass vs Class D
I built a class d amp for my son for xmas. It uses a generic (NXP??) board bought on eBay for US$25. The aluminum case cost twice that! Added a big surplus brick power supply.
It sounded very good. I didn't have the 10p speakers done, but it stood up OK to the Pass on my old JBLs. I prefer the F5, but like everything else audio, personal tastes win the day.
I have built a couple of class d amps from kits (41Hz) and from completed boards off of eBay. I don't think the 'tweaky' ones are worth the money, but I am sure there are a lot of opinions on these boards. The good news is that they are cheap and fun to experiment with. Not like playing around with tube amps or big FET amps.
I built a class d amp for my son for xmas. It uses a generic (NXP??) board bought on eBay for US$25. The aluminum case cost twice that! Added a big surplus brick power supply.
It sounded very good. I didn't have the 10p speakers done, but it stood up OK to the Pass on my old JBLs. I prefer the F5, but like everything else audio, personal tastes win the day.
I have built a couple of class d amps from kits (41Hz) and from completed boards off of eBay. I don't think the 'tweaky' ones are worth the money, but I am sure there are a lot of opinions on these boards. The good news is that they are cheap and fun to experiment with. Not like playing around with tube amps or big FET amps.
The NCore NC400 amps were trendy for a couple years. People rave about things that are new. After a while realitry sets in. How do they really sound?
I've noticed that many people make remarks about how much power you get for the money. To me that says it influences their perception of how it's going to sound. They want to like because it seems like a good value. Doesn't have to be great just not noticeably bad to get a thumbs up.
I've noticed that many people make remarks about how much power you get for the money. To me that says it influences their perception of how it's going to sound. They want to like because it seems like a good value. Doesn't have to be great just not noticeably bad to get a thumbs up.
F5 + loudspeaker impedance
Whout do you think about to connect a 14 Ohm impedance speaker to the normal F5? Increasing speaker impedance on the F5 means less power problems? Due to the push pull configuration?
Sorry, this is maybe a stupid question for the experts but I need some clarification on that... I don't have alle the formulas to calculate the output power for all different kind of amplifiers.
Thanks and Regards,
Mallard
Whout do you think about to connect a 14 Ohm impedance speaker to the normal F5? Increasing speaker impedance on the F5 means less power problems? Due to the push pull configuration?
Sorry, this is maybe a stupid question for the experts but I need some clarification on that... I don't have alle the formulas to calculate the output power for all different kind of amplifiers.
Thanks and Regards,
Mallard
Output voltage over DC speaker resistance will give you a general idea of the output current. Then multiply that by the output voltage again and youve got the output watts. Actual operation will be different because output is AC and the speakers resistance/impedance to different frequencies varies byt the calculation above will give you a good idea of possible output power into your speaker. Max output voltage depends on psu rail voltage. Actual output voltage depends on input voltage times amplifier gain limited by rail voltage.
Since F5 is running class A the power it draws from the psu is hugely different from what it dumps into the speaker. If you read Nelsons pdf on F5 it describes how to calculate this and he makes it easy to understand.
Since F5 is running class A the power it draws from the psu is hugely different from what it dumps into the speaker. If you read Nelsons pdf on F5 it describes how to calculate this and he makes it easy to understand.
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Hi Mallard,
Assuming sufficient current, for sinusoidal signal swinging between +/-V
through a purely resistive load R, the average power is V^2/(2R).
The voltage swing for the F5 is about +/20 volts, so for a 14 ohm load,
the power is about 14 watts.
Like Zen Mod said, almost halved compare to 8 ohm.
Assuming sufficient current, for sinusoidal signal swinging between +/-V
through a purely resistive load R, the average power is V^2/(2R).
The voltage swing for the F5 is about +/20 volts, so for a 14 ohm load,
the power is about 14 watts.
Like Zen Mod said, almost halved compare to 8 ohm.
Hum problem
Problem: I have connected the supply inversely (+ at - and - at +). It ran for 3 seconds, then the 0.47 ohm resistors began to glow ...
So I measured everything. The resistors still have the desired value as far as I can tell. The only burned part seemed to be the ZTX550 on one channel, which I replaced and it runs again and sounds well.
But I now have a little hum on the speakers. I wonder if that's from building a case or if there was more damage.
Any suggestions what else could probably be wrong? Any small defect in a part that now makes it hum?
If it's not a defect, how could building the case make it hum?
Problem: I have connected the supply inversely (+ at - and - at +). It ran for 3 seconds, then the 0.47 ohm resistors began to glow ...
So I measured everything. The resistors still have the desired value as far as I can tell. The only burned part seemed to be the ZTX550 on one channel, which I replaced and it runs again and sounds well.
But I now have a little hum on the speakers. I wonder if that's from building a case or if there was more damage.
Any suggestions what else could probably be wrong? Any small defect in a part that now makes it hum?
If it's not a defect, how could building the case make it hum?
