CFA IPS NEW TEST
Steps test:
Steps test:
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Great Thimios,
Have you auditioned it too? How does it sound to you? Do you like it?
How is it compared to your SA2015?
Have you auditioned it too? How does it sound to you? Do you like it?
How is it compared to your SA2015?
Almost there... Second channel is up and working properly!. I just need to complete the NS clamping voltage and high power testing for both channels.
Even without having done this final step, I cheated and connected a music source and a suicide speaker and it seems to be really good sound. I know this suicide speaker very good and I can tell, even if it is a bad speaker, if an amplifier has great potential and the NS OPS is one of them for sure. I just can't wait to listen on my main Troels ATS-4
Do
Even without having done this final step, I cheated and connected a music source and a suicide speaker and it seems to be really good sound. I know this suicide speaker very good and I can tell, even if it is a bad speaker, if an amplifier has great potential and the NS OPS is one of them for sure. I just can't wait to listen on my main Troels ATS-4
Do
NS is a great platform!Great Thimios,
Have you auditioned it too? How does it sound to you? Do you like it?
How is it compared to your SA2015?
It is a HI-class platform, very dynamic, very low distortion,very good sounding and can drive anything.😎
Up to now it isn't a completed amplifier,so i didn't have a stereo listening in my main speakers.
SA2015 is a copleted amplifier playing stereo in main speakers.
Very HI-END, for my ears,of cource.😉
I haven't built any bad amplifier but the comparison isn't my job,sorry!
I don't want to do something wrong.
Please look at the measurements,make your own if interesting,listen to this, build another listen again.....😱
Unfortunately i can't see any better.
I haven't reference speakers not golden ears.
Thanks, Thimios for your diplomatic answer. For sure the NSops is as good as it gets, i agree with you, but the IPS gives the amplifier its own acoustic signature. I was curious which one is your favorite. You must have one that sounds good to your ears than the other.
No isn't a diplomatic answer!Thanks, Thimios for your diplomatic answer. For sure the NSops is as good as it gets, i agree with you, but the IPS gives the amplifier its own acoustic signature. I was curious which one is your favorite. You must have one that sounds good to your ears than the other.

Please believe me.🙂
Nice work Jeff!
On my side amplifier is fully tested aside the high power test which I cannot do since I'm missing my scope... I'm still going to hook it up and play music since all other tests passed.
Do
On my side amplifier is fully tested aside the high power test which I cannot do since I'm missing my scope... I'm still going to hook it up and play music since all other tests passed.
Do
Regulated supplies for the front-end boards are a cool addition to NS Modular platform - "no compromise" builds are even less compromise now 😉
Nice board - separate +/- supplies for each channel.
Nice board - separate +/- supplies for each channel.
Jeff, Val
Nice work, separate PSU for the input boards is a step forward for sure!!
Looking forward to see the final build.
Regards
Peter
Nice work, separate PSU for the input boards is a step forward for sure!!
Looking forward to see the final build.
Regards
Peter
I think something is busted... I wanted to put it live and connected the amp on my R2R preamplifier (i know that with the R2R i sometimes get the relay thump at certain levels depending how many relay switches at the same time) and was playing music. While listening I turned up the volume a little bit at a time and then fuse on the PSU of the right channel busted... The amp went on standby. Disconnected the amplifier from AC, changed the fuse and disconnected the speaker load and tested the output for DC. The offset seems to be ok but now I hear the transformer humming every 20-30 sec as if there was a huge current draw then it stops humming again... Funny thing is the amp is still able to play music from both channels but fuse kept blowing on the right side.
Now I'm extremely down since I spent lots of money and time on this and I don't know if I have the courage of going through the debug of the module. When the amp is powered on, if I check for continuity on the ohm meter on the + - of the amp output, the left channel gives me ~4 ohms and right channel a dead short 0 ohm...
Could it be the IPS that is busted?
Thanks
Do
Now I'm extremely down since I spent lots of money and time on this and I don't know if I have the courage of going through the debug of the module. When the amp is powered on, if I check for continuity on the ohm meter on the + - of the amp output, the left channel gives me ~4 ohms and right channel a dead short 0 ohm...
Could it be the IPS that is busted?
Thanks
Do
That sounds more like a short in the output stage. Where are you measuring the continuity exactly? Have you had a scope connected to the output when the transformer hum is happening?
I kept everything off for an hour and plugged back in and it seem to have resolved by itself... I ran a 1Kh sinus with an 8 ohms load measuring accros the resistor for 10VAc and both channels responded equally
The amp does not seem to like hot plugging the speakers... I do this with my smaller much less powerful class A amps without issues but this has much more current output I guess... I know it is not good practice but I usually do this since I want to check the offset of the amp first before connecting my good speakers (4 ohms). I tend on not trusting speaker protection for the first few times...
In the PSUs, what fuse current rating would you recommend ?
Thanks
Do
The amp does not seem to like hot plugging the speakers... I do this with my smaller much less powerful class A amps without issues but this has much more current output I guess... I know it is not good practice but I usually do this since I want to check the offset of the amp first before connecting my good speakers (4 ohms). I tend on not trusting speaker protection for the first few times...
In the PSUs, what fuse current rating would you recommend ?
Thanks
Do
BTW, sorry if I come in a little edgy but there’s been a death in the family and my head is a little cloudy. Playing with this to keep me from thinking too much..
Do
Do
Sorry to hear about your loss Do.
It sounds odd that the issue fixed itself. Could the transformer hum have been caused by dirty mains power? Are there any factories near you? I normally install 15A rail fuses to protect the wiring from dead shorts and let the over-current protection take care of the amplifier itself. I often see discoloured fuses when I use lower rating (fuse distortion).
It sounds odd that the issue fixed itself. Could the transformer hum have been caused by dirty mains power? Are there any factories near you? I normally install 15A rail fuses to protect the wiring from dead shorts and let the over-current protection take care of the amplifier itself. I often see discoloured fuses when I use lower rating (fuse distortion).
Thanks
Ok, I'll order 15A fuses (125V or 250V?). I guess 7.5A 250V or 15A 125V..?
If something was wrong with the board (I don't have a scope at the moment, well I have two but I don't know how to make the more recent one work or it is defective.. The older one is a tube scope), would it still be able to output the 10Vac with 1KHz Sinus at input?
I know I really need to check with a scope and I will fiddle with it on a different amp to figure how it works... It is a 4 channel 100MHz scope with billions of functions. It was a gift but I'm lost with it... Maybe I can send a picture of the front panel and someone can tell me how to adjust it?
Thanks
Do
Ok, I'll order 15A fuses (125V or 250V?). I guess 7.5A 250V or 15A 125V..?
If something was wrong with the board (I don't have a scope at the moment, well I have two but I don't know how to make the more recent one work or it is defective.. The older one is a tube scope), would it still be able to output the 10Vac with 1KHz Sinus at input?
I know I really need to check with a scope and I will fiddle with it on a different amp to figure how it works... It is a 4 channel 100MHz scope with billions of functions. It was a gift but I'm lost with it... Maybe I can send a picture of the front panel and someone can tell me how to adjust it?
Thanks
Do
See when I told you my head wasn't all there...! I forgot to reconnect the over current protection cables. I hope nothing is busted
Do
Do
15A 250V is fine. Post some pictures of your scopes. Likely either will work, old CRT types give a better image and are much simpler to operate. You'll need 10x probes with either scope.
For quick and dirty initial testing I usually use a POS Velleman PCSGU250 USB scope. Very quick and simple to operate and accurate enough to verify operation.
For quick and dirty initial testing I usually use a POS Velleman PCSGU250 USB scope. Very quick and simple to operate and accurate enough to verify operation.
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