Thank you. Exactly the device I need! Guys, how would you make this wireless to connect it with the preamp that can't sit next to it? Any wireless repeater you'd recommend that will not impact sound quality too much?
I have my tuner and turntable in a room separate from my newer, main system. My main system has a WiiM Pro for streaming Roon, Qobuz, TIDAL, etc. My turntable and tuner are connected to a vintage Adcom GFP-555 preamp with the tape monitor output going to an Amazon Link preamp that used to be in my main system. The WiiM and the Amazon Link can be set up as an Echo group. So it goes turntable/tuner cabled to Adcom preamp cabled to Amazon Link wireless to WiiM Pro connected by optical to my main integrated amp. Even with the turntable source going through an ADC to DAC process the sound is very good to my ears when playing well-recorded LPs in good condition. I play vinyl and CDs mostly for older jazz reissues that aren't available through streaming services. In some case I prefer the mastering on those reissues to digital streams.
I also have a vintage Adcom GCD-700 5 CD changer cabled to the Amazon Link's coax in. That's a pure digital path from the CD changer to Amazon Link to WiiM Pro to my main integrated amp. I can't hear the difference between that and direct 16/44.1 streaming.
Might be pricier than you want to do from scratch, but worked well for me since I had already retired my Amazon Link preamp.
My main listening room is in my finished basement family room, 27 x 17 x 10 feet, perfect 7.5 foot equilateral triangle 18" from the front wall, concrete foundation on three sides, windows only above ear level. When I do EQ checks with REW I can see the El train on the graph before I hear it faintly, noise goes from 20 to 40 dB for about 10 seconds. But with music at 80 dB totally impossible to notice.Count yourself lucky. Mine is above that, more like 50dB. There is the airport in the next city, the train station about 1 km away, the train tracks 200m away, the Autobahn maybe 500m away, the school near me.
I looked up the situation in other cities, it's not rare to have more than 60dB sustained background noise.
My point is this, we all know that records and the technology around it is limited, but it's not as bad as some think it is.
Yes there are some points to measure. Check troubleshooting at muffsy.
The MC measurement (dash board) was done with 20 Ohm source impedance, so not too far from typical low output MCs. OTOH I don't konw the frequency dependency of a MC output impedance. The APs 20 Ohm are certainly constant over frequency.Sinad measurement of a phono stage must always include the output impedance of the cartridge.
We are way down at the fundamental noise source , the thermal noise. So a mc phono amp need a pickup to lower the hf noise. 10 ohm with mc pickup vs 200 ohms without
What would be the expected impact in sound quality due to the limited overload?This is an updated review of the Cambridge Audio Duo phono preamplifier. It is on kind loan from a member and costs US $349.
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The Duo has a solid build and is attractive to boot for its price. Back panel shows independent sets of inputs for moving magnet and coil cartridges:
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I like the inclusion of balance control and built-in power supply.
The original version was tested very early on when I had gotten into phono stage testing. My protocols have evolved since then making it hard to compare those measurements to current phono stage reviews.
Cambridge Audio Duo Measurements
It was challenging to reduce ground loops in both channels. After some messing around, I got close to optimal on both channels:
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This lands the Duo essentially at the top of the class:
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We still have that odd spikes around 19 kHz. Moving coil input naturally has lower SINAD due to much higher gain:
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Distortion is vanishingly low when measured without noise:
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RIAA equalization is essentially perfect in both modes:
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Headroom could be a bit better:
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Fortunately the same performance remains up to 10 kHz:
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While the cost has gone up $50, the Duo is still reasonably priced for a solid package both physically and electronically. The only miss is with respect to overload due to output maxing out at 10.5 volts. Otherwise we have excellent frequency response and state of the art in distortion in a phono stage.
My excellent recommendation rating for Cambridge Audio Duo remains.
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
Yikes! And the sound is...good??? I'd love to know how that measures. Honestly, that's the most extreme case I've ever heard of.Well I think I have 35-40ft of Canare L-3CB which is 55 pF/m, that puts me well above 200pF
Oh sorry, I'm using the stock Technics ~3ft cable + ground wire to get to the Phono Preamp, then it's 40ft RCAs from Preamp to Processor.Yikes! And the sound is...good??? I'd love to know how that measures. Honestly, that's the most extreme case I've ever heard of.
Have you considered having the phono pre-amp closer to the turntable and then running the long cables from it? You should at least compare how that sounds against your current set-up. MC cartridges are far less load dependent and could sound right with what you have, though it is still an extreme case.
Wait...could that be causing your problems???