Cambridge Audio Solo Phono Preamplifier Review

[guenthi_r]

One of the pics in your links is the older 640-something, I think. The Solo and Duo look very similar.

Variations in RIAA conformity can boil down to tolerance specified for the caps/resistors used for EQ. When I modded my phono stage, I ordered parts at 1% tolerance, but the same components are available at 2%, 5%, and 10%, at lower costs.

So it isn't necessary for the circuit to vary, the tolerance on the components can vary and alter the performance enough to show in measurements.

The pictures are the right. Maybe you should take a look into before posting.

 

[cgallery]

The pictures are the right. Maybe you should take a look into before posting.

They have pictures of the older 640 in one of those threads.

Regardless, the board layouts (auto-routers at work) are different but the MM stages appear to be about the same. Again, probably parts tolerances at play.

A 1% capacitor may cost 3-4x that of a 5% counterpart.

 

[dutchman]

Hello!
I bought the Alva Solo and have a problem with hum. Never had that problem with other pre amps. Can anybody help?

 

[Allar88]

I am not sure if this is fitting here, but in my setup, rega planar 3 -to- cambridge audio solo -to- dsp, i had a terrible hum and ground signal noise. After changing the cables, checking all ground loops, i decided to kill the ground on my solo, this was the only way how to get rid of the distortion caused by it. Maybe it will help other to get on track faster.

 

[dutchman]

I am not sure if this is fitting here, but in my setup, rega planar 3 -to- cambridge audio solo -to- dsp, i had a terrible hum and ground signal noise. After changing the cables, checking all ground loops, i decided to kill the ground on my solo, this was the only way how to get rid of the distortion caused by it. Maybe it will help other to get on track faster.

Yes, I had the same problem. But when I connect the ground cable of the turntable to the housing of the Amp, everything works finde. What does it mean, that you "killed the ground if the solo"?

 

[zonk]

I like the Phono Box. I should send it to Amir to measure.

Martin

Are you still planning to send your Pro-ject Phono Box RS to Amir to measure? I would be interested into the measurement as well.

 

[milw50717]

I am not sure if this is fitting here, but in my setup, rega planar 3 -to- cambridge audio solo -to- dsp, i had a terrible hum and ground signal noise. After changing the cables, checking all ground loops, i decided to kill the ground on my solo, this was the only way how to get rid of the distortion caused by it. Maybe it will help other to get on track faster.

FWIW From the factory Rega internally wired the ground to the left output RCA and much has been written about the "Rega hum". I have a Planar 2 that I rewired with a kit that has a separate ground wire that I use with the Solo and I have not experienced any hum or ground noise. The ground terminal on the Solo is connected to the ground on the power socket and not the RCAs. Thus a Rega with the original wiring configuration will have the TT ground passed through the Solo RCAs to the amp, but not so in my case.

 

[Mr Vinyl]

Hello!
I bought the Alva Solo and have a problem with hum. Never had that problem with other pre amps. Can anybody help?

No hum on mine. Many things can cause that - turntable proximity to the power amp, power lines, etc. Is your setup 100% identical to what it was previously?

 

[Angsty]

No hum on mine. Many things can cause that - turntable proximity to the power amp, power lines, etc. Is your setup 100% identical to what it was previously?

Using a ground wire?

 

[dutchman]

No hum on mine. Many things can cause that - turntable proximity to the power amp, power lines, etc. Is your setup 100% identical to what it was previously?

Yes, the setup is the same as before. The solution was not to use the earth connection on the solo but to make the earth connection via the stereo amplifier.

 

[jbonn5000]

I've also run into an interesting hum problem. It's a rather loud buzz. I have a Fluance T82 and a custom U-Turn Orbit (why I have both of these is a long story). The Orbit is completely clean. The Fluance has a super loud buzz. I have the ground connected to the Solo pre and even tried an additional cable to my processor (Anthem AVM 70). I've also tried a ground to the Solo, and another from the Solo to the processor. Same problem. A couple of odd things. 1) the loud buzz came out of nowhere. It was clean at first and then started buzzing randomly. 2) The buzz does not exist when I try the built-in pre on the AVM nor a cheap Behringer pre I had in my office. So it's specific to the Solo. Any ideas?

 

[Bob from Florida]

I've also run into an interesting hum problem. It's a rather loud buzz. I have a Fluance T82 and a custom U-Turn Orbit (why I have both of these is a long story). The Orbit is completely clean. The Fluance has a super loud buzz. I have the ground connected to the Solo pre and even tried an additional cable to my processor (Anthem AVM 70). I've also tried a ground to the Solo, and another from the Solo to the processor. Same problem. A couple of odd things. 1) the loud buzz came out of nowhere. It was clean at first and then started buzzing randomly. 2) The buzz does not exist when I try the built-in pre on the AVM nor a cheap Behringer pre I had in my office. So it's specific to the Solo. Any ideas?

The Orbit uses an AC adapter while the Fluance uses a switcher power supply. Buzzing usually indicates 120 HZ ripple, but with a switcher, things are different dependent on the frequency used. The Solo uses a grounded power cord which increases ground loop possibilities if any other components connected also have grounded power cords. We need to break the loop for troubleshooting purposes. Get a ground "cheater" adapter for your Solo power cord and see if the "buzzing" goes away. If it does then you know it is a ground loop induced issue and you can remove / substitute other components until isolated. It may not go away. In that case try replacing the switcher wall wart that came with your Fluance. Those switchers can radiate noise that may be picked up by the Solo and not other phono preamps.

 

[jbonn5000]

The Orbit uses an AC adapter while the Fluance uses a switcher power supply. Buzzing usually indicates 120 HZ ripple, but with a switcher, things are different dependent on the frequency used. The Solo uses a grounded power cord which increases ground loop possibilities if any other components connected also have grounded power cords. We need to break the loop for troubleshooting purposes. Get a ground "cheater" adapter for your Solo power cord and see if the "buzzing" goes away. If it does then you know it is a ground loop induced issue and you can remove / substitute other components until isolated. It may not go away. In that case try replacing the switcher wall wart that came with your Fluance. Those switchers can radiate noise that may be picked up by the Solo and not other phono preamps.

Thanks for such a knowledgeable response! I plugged the Solo into a ground adapter similar to this one. The buzz went completely away. However, I happened to turn off the ceiling fan in that room and heard pop through my speakers lol, which is repeatable. I have the adapter/Solo combo plugged into a power strip so perhaps the issue there (no screw touching the lift part of the ground adapter, if that matters).

In any case, I might have to return the Fluance to just straight up avoid any of these issues.