Distorsion due to RFI at amp output
I am looking for this article :
"Resonances & Repercussions". P.Miller. Hi-Fi News & Record review. June 1989 pp35,37
It deals with RFI at the amp output having distorsion effects in the audio band.
Thanks in advance.
I am looking for this article :
"Resonances & Repercussions". P.Miller. Hi-Fi News & Record review. June 1989 pp35,37
It deals with RFI at the amp output having distorsion effects in the audio band.
Thanks in advance.
Thanks Jorge.
In his article, Paul Miller says that the Deltec DPA-50S power amp was he least suceptible to RFI, because of exceptional open-loop linearity, of the amps he tested. Does anybody know how this linearity is achieved ?
In his article, Paul Miller says that the Deltec DPA-50S power amp was he least suceptible to RFI, because of exceptional open-loop linearity, of the amps he tested. Does anybody know how this linearity is achieved ?
I don't have that article, although I may have read it back then.
Particularly with the much longer speaker leads of rear surround channels, it was suggested to wind a couple of turns of the speaker leads through a toroid near the amplifier output. At the time , I lived only a couple of kms from the Sydney TV towers and used to hear low level "frame buzz" .The toroids cured the problem.
SandyK
Particularly with the much longer speaker leads of rear surround channels, it was suggested to wind a couple of turns of the speaker leads through a toroid near the amplifier output. At the time , I lived only a couple of kms from the Sydney TV towers and used to hear low level "frame buzz" .The toroids cured the problem.
SandyK
There a great interest from people of this forum for Paul Miller's article. Maybe it's time to start a discussion.
Before using tricks to avoid intrusion of RFI into an amplfier, I would like to know if some topologies are less susceptible to others from this point fo view. Tube amps are known to be.
My first question is : is the inverting scheme with its virtual ground input more suscpetible than the non-inverting scheme concerning intermodulation with, and demodulation of, unwanted high frequency signals ?
Before using tricks to avoid intrusion of RFI into an amplfier, I would like to know if some topologies are less susceptible to others from this point fo view. Tube amps are known to be.
My first question is : is the inverting scheme with its virtual ground input more suscpetible than the non-inverting scheme concerning intermodulation with, and demodulation of, unwanted high frequency signals ?
i think non-inverting is more susceptible, non-inverting usually have worse transient response.
We must depend on some kind of filter, if we push the amp to operate at very high frequency, THD and other factors will degrade.
output coil is not very helpful in this regard, inside the amp it will act as antenna and spray the rf everywhere.
adding ferrite at the output increases THD, I guess we just have to live with that. or add shielding to speaker cable and enclosure, ala tannoy
We must depend on some kind of filter, if we push the amp to operate at very high frequency, THD and other factors will degrade.
output coil is not very helpful in this regard, inside the amp it will act as antenna and spray the rf everywhere.
adding ferrite at the output increases THD, I guess we just have to live with that. or add shielding to speaker cable and enclosure, ala tannoy
Hi Peufeu,
Yes the article has been sent to the first address you gave me.
I am going to send it to the second address.
Yes the article has been sent to the first address you gave me.
I am going to send it to the second address.
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