Ground Loop, Phono Amp, Buzz eliminator, weak volume,

[Nolan Olson]

Hi,
I had a previous post about complete hum on phono. So I bought a new receiver ( new to me)
Everything works except phono. Now I can hear very faint music and a hum. I had my cartridge refurbished by Sound Smith and upgraded from a MMC 5 to an MMC 3. I have tested the arm sockets and the cartridge pins with 490 and 890 ohms respectively.
My wife thinks I should buy a new TT but I love the looks and feel of the B&O RX. My question is where to go from here? I am considering a Pluto phono amp (5 star reviews) or a ROLLS HE 18 Buzz Off Hum Eliminator. Would either solve my problem? And if I buy one can I run it through my Tape 2 L&R Play Sockets? I use the single Aux for my CD and I doubt I should use phono jacks with a phono amp? I’m lost, at my wits end, any help would be appreciated. As a note, the RX does not have grounded rca cables and they are connected inside of TT.
Thanks
Nolan

 

[Grenadeslio]

Hi,
I had a previous post about complete hum on phono. So I bought a new receiver ( new to me)
Everything works except phono. Now I can hear very faint music and a hum. I had my cartridge refurbished by Sound Smith and upgraded from a MMC 5 to an MMC 3. I have tested the arm sockets and the cartridge pins with 490 and 890 ohms respectively.
My wife thinks I should buy a new TT but I love the looks and feel of the B&O RX. My question is where to go from here? I am considering a Pluto phono amp (5 star reviews) or a ROLLS HE 18 Buzz Off Hum Eliminator. Would either solve my problem? And if I buy one can I run it through my Tape 2 L&R Play Sockets? I use the single Aux for my CD and I doubt I should use phono jacks with a phono amp? I’m lost, at my wits end, any help would be appreciated. As a note, the RX does not have grounded rca cables and they are connected inside of TT.
Thanks
Nolan

Moving coil into a moving magnet input?

 

[WaynerN]

There is your problem.

 

[rothwellaudio]

You don't need a "buzz off" or any other gadget, and you probably haven't got an earth loop. You have a simple problem which is as yet unidentified. More info might help.

 

[rothwellaudio]

Moving coil into a moving magnet input?

There is your problem.

Yes, if it's a low output moving coil cartridge into a moving magnet phono input, that's a problem.

 

[swechsler]

MMC cartridges are considered moving iron, not moving coil (MMC stands for moving micro-cross; if you can find a vintage ad for a B&O cartridge it will show a pic of why they called it that). The output from an MMC cartridge should be the same (or at least the same order of magnitude) as a standard MM cartridge.

ETA: found a picture

 

[Nolan Olson]

I don’t know much about MM and MC. I just read this article below which help explains but I need advice
on what to do next. The article says to buy a preamp that supports MC cartridges rather than MM? Do you agree and have any reasonable priced suggestions on a make or model or buy used? If not that then buy an a used TT that is MM rather than MC? Any recommendations? The Receiver I bought is an MCS 3253 and just Installed. It receives and plays FM beautifully and the tapes play better though the equalizer than my previous receiver. I’m on SS so funds are limited.
Thanks for your help.
Nolan

 

[Nolan Olson]

MMC cartridges are considered moving iron, not moving coil (MMC stands for moving micro-cross; if you can find a vintage ad for a B&O cartridge it will show a pic of why they called it that). The output from an MMC cartridge should be the same (or at least the same order of magnitude) as a standard MM cartridge.

ETA: found a picture

Excellent illustration!

 

[Nolan Olson]

Excellent illustration!

So where do I go from here? Do I buy a preamp and if so do you have an example... I was looking at a Pluto on Amazon. And the same question, can I plug a phono pre amp into a Tape 2 play L&R rca sockets? If not I have to buy a different phono that gives good volume thur my phono jacks.
thanks for your reply
Nolan

 

[Nolan Olson]

PS the MCS 3253 has two phono hookups the second pair sealed with caps that have become unremovable with 40 years of non use. I ordered some Dioxit to see if I can clean them and get them to release. Any thoughts?

 

[rothwellaudio]

The output from an MMC cartridge should be the same (or at least the same order of magnitude) as a standard MM cartridge.

So that's not the problem then.

If not that then buy an a used TT that is MM rather than MC?

Turntables are neither MC nor MM. Cartridges are MC or MM, or in this case MMC.

So where do I go from here? Do I buy a preamp...

That shouldn't be necessary if the cartridge puts out roughly the same signal level as an MM.

can I plug a phono pre amp into a Tape 2 play L&R rca sockets?

Yes, if you did buy an outboard phonostage that would be one possible way to use it.

 

[Nolan Olson]

I looked at MC phono amps and they start at $350.
Although I have $300 in the RX and retipped cartridge I am probably better to sell it and buy a preamp TT from some vendor I can return it to if it doesn’t work with my system. But I love the design and concept features of the RX... just want to listen to some old folk music LPs. Thanks for your input.
Nolan

 

[rothwellaudio]

I looked at MC phono amps and they start at $350.
Although I have $300 in the RX and retipped cartridge I am probably better to sell it and buy a preamp TT from some vendor I can return it to if it doesn’t work with my system. But I love the design and concept features of the RX... just want to listen to some old folk music LPs. Thanks for your input.
Nolan

The Bang & Olufsen MMC3 cartridge has an output of 2.12mV according to the Vinyl Engine database. It works into a standard mm phono input. You don't need an outboard phonostage and an MC phonostage is the last thing you need.
Whatever the problem is, selling the turntable (or did you mean sell the cartridge?) is a sledgehammer to crack a nut. I suspect the cartridge isn't wired up correctly.

I have tested the arm sockets and the cartridge pins with 490 and 890 ohms respectively.

I'm not exactly sure what you meant by that, but it looks suspicious to me. It could be that one reading is the resistance of one coil and the other reading is the resistance of both coils in series. That would suggest the cartridge isn't wired correctly. If that's the case, just wire it up correctly and you won't have to sell the turntable or buy anything else.