It is possible, but you must have some internal shield or can for the transformer.
If I place my RIAA chassis on top of the PSU chassis, it will hum. Once there is about 12-18 inches between the 2 chassis, it's silent.
Perhaps you might want to get a very small box for the transformer, and put the rest in the big box?
If I place my RIAA chassis on top of the PSU chassis, it will hum. Once there is about 12-18 inches between the 2 chassis, it's silent.
Perhaps you might want to get a very small box for the transformer, and put the rest in the big box?
I really second those 2 ideas. Whilst running former in another housing may seem troublesome, extra work, extra umbilical and connectors, but I can say by experience it's really worth it. Nothing worse than having extra hum whilst using a low cart output, that you chose for delicateness' of sound !!!!
Best,
nAr
Thanks guys. I know its a significant benefit to have a separate PSU since this is a DIY project building from scratch, whereas people have to accept the commercial 1 box version as built. Seeing a picture of the internals of XP15 tells me its alright to copy the same layout, morover the tranny doesn't look shielded. I intend to shield it. Afterall countless pre amps manufactured are 1 box. I've planned to have a pair of Cinemag SUT at the input. Its also intended for MC mode only. Thats why I'm still looking to reduce the gain to 40db maximum.
I'm going to give it a try to mount the PSU the same way as XP15 and see if any issues crop up. If I can get away from 2 box, I'll be a happy camper.
Pic taken from the internet.
I'm going to give it a try to mount the PSU the same way as XP15 and see if any issues crop up. If I can get away from 2 box, I'll be a happy camper.
Pic taken from the internet.
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A single box may work depending on the transformer. The XP15 transformer is shielded and actually is now double shielded and uses a low noise design. I tried an off the shelf unit and noise was 20 dB higher. They are also rotated for best noise on the original Ono they we're at 90 degrees.
Since the Pearl Two is already a MC phono preamp, why would you need additional step-up transformers?
That's exactly is to be expected.
R28 with 100ohm resistor = MC phono preamp
Without R28 = MM phono preamp
Supposed to be like this, no?
Or you could try a 3 box solution.
Regards David.
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Yes, that chassis will work, and nicely!
The PSU won't fit, but that can be built in a much smaller (and uglier, as it can be hidden...) case.
As mentioned, do pay attention to the height of your heatsinks and big caps. But it shouldn't present a problem.
It's a fantastic phono stage. Of my DIY phonostages, only the original Pearl is anywhere close to as good.
The PSU won't fit, but that can be built in a much smaller (and uglier, as it can be hidden...) case.
As mentioned, do pay attention to the height of your heatsinks and big caps. But it shouldn't present a problem.
It's a fantastic phono stage. Of my DIY phonostages, only the original Pearl is anywhere close to as good.
Yes, that chassis will work, and nicely!
The PSU won't fit, but that can be built in a much smaller (and uglier, as it can be hidden...) case.
As mentioned, do pay attention to the height of your heatsinks and big caps. But it shouldn't present a problem.
It's a fantastic phono stage. Of my DIY phonostages, only the original Pearl is anywhere close to as good.
Thanks to both of you!
I've got three of those cases, so I was hoping to fit the phono in one, line stage in another, and the third would house raw DC supplies for both. The cases look exactly like this, except without any knobs (yet):
An externally hosted image should be here but it was not working when we last tested it.
