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Making Mono - When Two Become One ?

Big Tabs

Big Tabs

looking backwards, going forwards
Is it possible to wire an Audio Technica VM95C (conical stylus) so that it works as a mono cartridge for 1950’s - 1960’s 33-1/3 Mono L.P’s?

I don’t have a mono button on any of my amps.

I do not require the cartridge to play 78’s - I have an old Hacker record reproducer for that.

The Y-connection thing that I have read about is too complicated for my head, unless there is a commercially available thing that I can buy.

The cheap AT VM95C seems a reasonable choice for this - I don’t want to spend loads for the few jazz vocal albums that I have, but I would like to know if I can do better than the stereo cartridges I have.

A simple drawing / diagram of cartridge with what needs connecting were would be grand, or a link to same - if it exists.

Muchos grassyarse in advance.
 
Any stereo cartridge can be strapped for mono. Simply use some fuse wire and wrap the red and white pins together, then the green and blue pins together. Done.
 
smegger68 said:
Any stereo cartridge can be strapped for mono. Simply use some fuse wire and wrap the red and white pins together, then the green and blue pins together. Done.
Click to expand...

Is that all?

I don’t know the term ‘strapped,’ I guess that means modified?

does the fuse wire need to be a particular type?

Does it need to be soldered?
 
Here's an example (found on the Steve Hoffman forum).

I've done this on a spare Shure M44 using some strands of copper from a bit of speaker cable. Was a bit fiddly to get them wrapped tightly. I didn't worry about soldering - the cartridge tags go on afterwards and keep everything in place.

Strapped just means you're literally strapping the two pins together.


5469643177_350dfa6493.jpg
 
paulfromcamden said:
Here's an example (found on the Steve Hoffman forum).

I've done this on a spare Shure M44 using some strands of copper from a bit of speaker cable. Was a bit fiddly to get them wrapped tightly. I didn't worry about soldering - the cartridge tags go on afterwards and keep everything in place.

Strapped just means you're literally strapping the two pins together.


5469643177_350dfa6493.jpg
Click to expand...


thanks
 
If one truly wishes to 'Ac-Cent-Tchu-Ate the Positive' of mono record replay, better to wire the two channels in series for standard 'lateral modulation' mono records. In this way any vertical modulation/noise is cancelled at pickup.

Basically, this involves strapping R+ve (red) to L-ve (blue) and only connecting the two remaining unstrapped pins to tonearm, specifically R-ve (green) and L+ve (white). Wired this way L+ve pin carries R+ve + L+ve signal and R-ve pin carries R-ve + L-ve signal.

As bonus, with cartridges like Ortofon's LM/OM/2M series where the tiny generator enclosure necessitates that the physical layout of the pins have the L and R pairs crossing paths, there is only the one wire link, so no need to insulate the wires such that one doesn't short the other (rather ironic, I know). The downside being that there will be two tonearm wires excluded with a mono pair that need be summed elsewhere for connection to stereo amps (some double these tags up at each of the two connected cartridge pins while others might use RCA 'Y' connectors down the amp end).

Here is Shure's old mono wiring diagram for SC35C; that's series on the left and parallel on the right...

cablage.jpg
 
Forgive the numptiness of this question, but how does this outcome - modding the cartridge – differ from pressing a mono button on a preamp? I understand the OP doesn't have such a button. I'm just curious about the way(s) mono sound gets produced from a stereo recording.
 
kasperhauser said:
Forgive the numptiness of this question, but how does this outcome - modding the cartridge – differ from pressing a mono button on a preamp? I understand the OP doesn't have such a button. I'm just curious about the way(s) mono sound gets produced from a stereo recording.
Click to expand...
Good question.

A mono button on a pre-amp will strictly sum the two channels, not taking into account that any vertical modulation* and/or noise that a stereo phono cartridge retrieves and sends (lots) should have be cancelled at source. This none intentional signal related noise will be passed along and amplified.

Electrically, the difference in performance between a modern stereo cartridge with the coils wired in series vs. a modern dedicated mono cartridge is nil. Take Ortofon Stylus 2M Blue on 2M Blue vs. Stylus 2M Blue on 2M Mono body, same thing but for an elliptical tip; the irony being that Stylus 2M Mono with nude conical is priced at €252, whereas, Stylus 2M Blue with nude elliptical having the same major radius is €168.

* all the more prevalent with conical tips due to HF tracing related 'pinching' affect.
 
Craig B said:
If one truly wishes to 'Ac-Cent-Tchu-Ate the Positive' of mono record replay, better to wire the two channels in series for standard 'lateral modulation' mono records. In this way any vertical modulation/noise is cancelled at pickup.

Basically, this involves strapping R+ve (red) to L-ve (blue) and only connecting the two remaining unstrapped pins to tonearm, specifically R-ve (green) and L+ve (white). Wired this way L+ve pin carries R+ve + L+ve signal and R-ve pin carries R-ve + L-ve signal.

As bonus, with cartridges like Ortofon's LM/OM/2M series where the tiny generator enclosure necessitates that the physical layout of the pins have the L and R pairs crossing paths, there is only the one wire link, so no need to insulate the wires such that one doesn't short the other (rather ironic, I know). The downside being that there will be two tonearm wires excluded with a mono pair that need be summed elsewhere for connection to stereo amps (some double these tags up at each of the two connected cartridge pins while others might use RCA 'Y' connectors down the amp end).

Here is Shure's old mono wiring diagram for SC35C; that's series on the left and parallel on the right...

cablage.jpg
Click to expand...


christ on a bike, that really hurt my head reading that - it might as well be a foreign language.

After writing out what I think you mean -

is this what you are saying?

1) connect Red to Blue on the cartridge pins with wire

2) only connect Green and White to the tonearm pins

3) Green and White are NOT connected with wire to each other.


Is that the simple translation?
 
Nagraboy said:
@Big Tabs

I knew that Andrews Sisters LP would convert you Peter! ;)
Click to expand...

I have a few mono albums from 1950’s/1960’s, mostly jazz, mostly vocal.

As I have a few spare cartridges and headshells, it was just a case of finding out what connects to what.

Having set up an AT 110E cartridge as per @smegger68 suggested, I am not yet convinced it sounds much different to using a stereo enabled cartridge.

Mind you, I think a conical stylus profile might be better.
 
Big Tabs said:
christ on a bike, that really hurt my head reading that - it might as well be a foreign language.

After writing out what I think you mean -

is this what you are saying?

1) connect Red to Blue on the cartridge pins with wire

2) only connect Green and White to the tonearm pins

3) Green and White are NOT connected with wire to each other.


Is that the simple translation?
Click to expand...
Yes.

(@deebster, Déjà vu?)
 
Big Tabs said:
I have a few mono albums from 1950’s/1960’s, mostly jazz, mostly vocal.

As I have a few spare cartridges and headshells, it was just a case of finding out what connects to what.

Having set up an AT 110E cartridge as per @smegger68 suggested, I am not yet convinced it sounds much different to using a stereo enabled cartridge.

Mind you, I think a conical stylus profile might be better.
Click to expand...
The series strapping method will sound better.
 
I got this external switch from eBay last week (below). Works a treat with my stereo SPU between phono and integrated.

I’ve heard you can make a cable (with internal resistors added) to link your tape in/outs together and just flip to tape monitor to put it in circuit and get mono playback.

QcyNytH.jpg
 
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