Phono 3 / RFI problems
Posted: Sun Feb 10, 2019 10:32 pm
When I purchased the Phono 3 last year (I use a phono 3 with one BBPSU), I had it set by Richard to MC mode.
Originally, I bought a phono 2 mm version in late 2017, which I used with my BBPSU and a dedicated MC step-up transformer. The music this MM version made was fantastic to my ears! . (Read my report from Dec. 2017 in the NVA review section on page 17). RFI-noise was not discernible with the MM version, there was only a slight hum detectable as I listen with a high efficient horn ls. I could reduce this hum by floating (no earth connection) the BBPSU. (The only thing this MM version didn't like was a mobile phone in the listening room as this caused some interference noise through my speakers. But I never have my mobile phone with me, when I listen to music - so no problem... )
Then I had my Phono 2 set to MC by Richard and on the way back to Austria the case of the Phono 2 MC was damaged during transport. Hooked up to my system it sounded very good, but there was RFI-noise heard over my horn ls-system. Richard immediately offered to take the phono 2 back as apparently the transport damage caused some internal problems, too.) As at that time, also the phono 3 was newly available, I decided to upgrade my returned Phono 2 to a Phono 3 MC version set for usage with one BBPSU only.
This Phono 3 MC version made it safe to my house and the musical enjoyment started again (see my feedback in the review section on Page 20). The only negative was - as before with the Phono 2 MC - RFI-noise with the Phono 3 MC version connected to my system over the horn speakers. The RFI-noise was at that time less audible then with the Phono 2. This noise became a bit stronger over time (sometimes it is better, sometimes it's worse) and in the meantime the musical pleasure I had at the beginning and especially with the Phono 2 set to MM is no longer there.
It seems to me that something isn’t 100% right with my Phono 3 MC. I wonder if due to my 98dB efficient speakers, the super minimalistic design Richard uses for his phono stages would be better served with a Phono 3 set to MM-mode and dedicated step-up than set to MC-mode?
Has someone here in the forum with high sensitive speakers encountered similar RFI-noise problems with a NVA phono stage in MC mode?
My other two phono stages (Graham Slee Revelation and pimped EAR 834) don't have such a RFI problem with the same MC cartridges connected (Lyra Skala and AT OCC30) through my Lenco L75 / Schick 12" tonearm combo.
I tend to ask Richard to have a look at the phono 3 unit and return it for inspection.
Question to Richard:
Can there be something done to get the phono 3 to be less prone to RFI-noise ithout sacrificing the musical qualities?
Feedback highly appreciated!
Thanks,
Norbert
Originally, I bought a phono 2 mm version in late 2017, which I used with my BBPSU and a dedicated MC step-up transformer. The music this MM version made was fantastic to my ears! . (Read my report from Dec. 2017 in the NVA review section on page 17). RFI-noise was not discernible with the MM version, there was only a slight hum detectable as I listen with a high efficient horn ls. I could reduce this hum by floating (no earth connection) the BBPSU. (The only thing this MM version didn't like was a mobile phone in the listening room as this caused some interference noise through my speakers. But I never have my mobile phone with me, when I listen to music - so no problem... )
Then I had my Phono 2 set to MC by Richard and on the way back to Austria the case of the Phono 2 MC was damaged during transport. Hooked up to my system it sounded very good, but there was RFI-noise heard over my horn ls-system. Richard immediately offered to take the phono 2 back as apparently the transport damage caused some internal problems, too.) As at that time, also the phono 3 was newly available, I decided to upgrade my returned Phono 2 to a Phono 3 MC version set for usage with one BBPSU only.
This Phono 3 MC version made it safe to my house and the musical enjoyment started again (see my feedback in the review section on Page 20). The only negative was - as before with the Phono 2 MC - RFI-noise with the Phono 3 MC version connected to my system over the horn speakers. The RFI-noise was at that time less audible then with the Phono 2. This noise became a bit stronger over time (sometimes it is better, sometimes it's worse) and in the meantime the musical pleasure I had at the beginning and especially with the Phono 2 set to MM is no longer there.
It seems to me that something isn’t 100% right with my Phono 3 MC. I wonder if due to my 98dB efficient speakers, the super minimalistic design Richard uses for his phono stages would be better served with a Phono 3 set to MM-mode and dedicated step-up than set to MC-mode?
Has someone here in the forum with high sensitive speakers encountered similar RFI-noise problems with a NVA phono stage in MC mode?
My other two phono stages (Graham Slee Revelation and pimped EAR 834) don't have such a RFI problem with the same MC cartridges connected (Lyra Skala and AT OCC30) through my Lenco L75 / Schick 12" tonearm combo.
I tend to ask Richard to have a look at the phono 3 unit and return it for inspection.
Question to Richard:
Can there be something done to get the phono 3 to be less prone to RFI-noise ithout sacrificing the musical qualities?
Feedback highly appreciated!
Thanks,
Norbert