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Making Mono - When Two Become One ?

Craig B said:
I was just editing my previous post when you posted yours.

Have another read of mine. It's a bit wordy but I hope mostly jargon free.

Here's an updated diagram. White lead is black so that it is visible. Just ignore the word 'masse', French for 'mass', in this case a reference to green being also connected to the cartridge shield as part of the design. Yes, I stole this from the ancient Shure Bros. Francophone text instructions for model SC35C.

Series-Mono.jpg
Click to expand...

I have put the Sex Pistols on, now it is Round (?) #7 playing with stuff I barely understand.
See what I can break this time (lots of tags snapped off the cartridge connecting wires, I have ordered more to ruin )

First job - make a drawing plan.
 
… I couldn’t cut up more headshell leads as I only have 4 spare left ( broke the rest over the last few days)

so I took inspiration rather than following a recipe.

no splicing of headshell leads.

I did this o_O - what I have illustrated by means of a picture that I did draw. Just.

No scale…

Played a few albums, sounds good, much bass, no humming or buzzing.

If it is wrong, please tell me how it is wrong (in simple terminology please.)

sounds fine.

2-AFA2-BD3-5-DAA-423-C-B0-EA-D34-C31-CF5-A78.jpg
 
F*ck me! That should be hung in the Louvre.

That is the same circuit as I was describing, only you've strapped the positives and negatives at the headshell pins end rather than doubling the wire connections up at the cartridge pins end (which, of course, is what you were describing yesterday).

Regardless, electrically it's the same thing, so good work!

Must be off, have to tear up my art portfolio now.
 
Craig B said:
Regardless, electrically it's the same thing
Click to expand...

That is good news.

I was talking to The Wife, concerned as to the actions I was taking - if it was totally wrong I would expect-
no sound
only one speaker
? out of phase
buzzing or constant hum.
*Sheet Sound*

There is a pleasant amount of bass.
odd bits of surface noise seems reduced/pushed into the far background.

That will do me for the moment. Until fresh Ears advise me otherwise.
 
Big Tabs said:
odd bits of surface noise seems reduced/pushed into the far background.
Click to expand...
Yes, this is one of the advantages of wiring the cartridge for mono in this fashion.

Of course, the other biggie being not having to change anything round other than a cartridge/headshell swap for those times that you want to play mono records.

I'm happy for you that you got there in the end, especially so, without seriously depleting the national reserve of headshell leads. :)
 
Craig B said:
Yes, this is one of the advantages of wiring the cartridge for mono in this fashion.

Of course, the other biggie being not having to change anything round other than a cartridge/headshell swap for those times that you want to play mono records.

I'm happy for you that you got there in the end, especially so, without seriously depleting the national reserve of headshell leads. :)
Click to expand...


I think they were fragile as they were 1970’s jobbies.

Ordered more from ebay, for when I next get a bright idea.
 
paulfromcamden said:
That's a very ace drawing! I'm going to try this configuration when I get a mo.
Click to expand...

Let us know how it goes.

I am very pleased, the modification has changed a collection of Mono records that sounded okay when played with a stereo cartridge into something that sounds more genuine and full of life.

Yesterday I trawled through a pile of records in my spare room and dug out some Mono records that I like but the sound on playback has left me flat. I cleaned them up, and left them drying - so today I get to listen to them in a fresh light.

The modification took me a while because I am slow. I needed a lot of extra light, a lamp with integral magnifying glass and a white sheet of paper as a base to work on to increase light/visibility.

The ‘strapping’ was single strands of thin copper wire, wrapped in a figure of eight for a few turns.

Had to do the work at the kitchen table, most light and better seating to avoid backache :)
 
I was just about to start a thread on this very thing. I have a spare headshell and leads, and was thinking of a simple nice sounding cartridge with a conical stylus that wasn't too far from the dimensions of the Hana ML so I didn't need to faff with VTA/or re calibtae weight too far every time I fit it. I have a HUGE collection of mono classics I want to go through, and old blues and jazz to boot. Great thread and despite the headache, that final Artwork BigTabs is perfik, I understand!.
Now I just need to find a cheapish cart with conical stylus to do the work. Anyone know of a cheap low output MC that would suit....conical stylus/ middling output (o,3 - 0.5g) less that 10g etc?
Whistling Dixie i expect but you never know.
 
Why not just buy a mono cartridge? At the end of the day it's a lot of faffing to achieve the same result. The AT33Mono is under £400.
 
Rockmeister said:
When I made the post I was imagining using a simple moving magnet. A base AT95 would do it and save hundreds. I would have to reset the phono stage each time but it’s 5 mins work.
Click to expand...


The AT VM95 Conical (£29) is great - I just have to set the tracking force/bias which takes a couple of minutes, well worth it.
It also means that I am not shying away from Mono albums when I come across them.

The idea of @montesquieu of spending “less than £400” o_O on something that I will use only on occasion seems wasteful.

I would be interested to hear how you get on with it @Rockmeister and what you think of the end product/sound.
 
Moi aussie...I listen to loads of mono stuff of Spotify and it sounds GREART, has a real character. About 10 years back I set my 18 year old grand-neice up with a Vinyl starter system. A sansui direct drive was fitted with an AT 95, and before playing, I said to her, that one day, we could make the xound 'better' if she had some cash with another cartridge. I'd never heard an AT 95. After half an hour of record swapping she said....'how could this BE better'. I had to agree. I don't think there is a better sound for your pound than tat range of cartridges, and moving 2 switches on the phono stage isn't too bad.

However what I have realised is that my spare SME headshell can't adjust for overhang. To get the hana right, the arm had to be pushed right to back of it's sliding base. Never had that happen before and I very much doubt that the 95 series will fit the same. Overhang will be way out; So my solution will be a new headshell with slots for mounting so i can adjust that end just the once. That however is cash, so I've got to some looking/asking around and see what's what.

I'll let you know BigT how I get on if I find a solution I can afford.

Off to ebay to find an adjustable headshell with a mass close to the SME.
 
Big Tabs said:
… I couldn’t cut up more headshell leads as I only have 4 spare left ( broke the rest over the last few days)

so I took inspiration rather than following a recipe.

no splicing of headshell leads.

I did this o_O - what I have illustrated by means of a picture that I did draw. Just.

No scale…

Played a few albums, sounds good, much bass, no humming or buzzing.

If it is wrong, please tell me how it is wrong (in simple terminology please.)

sounds fine.

2-AFA2-BD3-5-DAA-423-C-B0-EA-D34-C31-CF5-A78.jpg
Click to expand...

That's excellent! And just so I know I've got this right, the wiring setup is:

- strap red and blue pins on cart
- strap red and white pins on headshell

- connect green pin to green pin
- connect white pin to white pin

Assuming that's right, do you have to change any capacitance settings on the phono stage?
 
windhoek said:
That's excellent! And just so I know I've got this right, the wiring setup is:

- strap red and blue pins on cart
- strap red and white pins on headshell

- connect green pin to green pin
- connect white pin to white pin

Assuming that's right, do you have to change any capacitance settings on the phono stage?
Click to expand...

yes

Follow the wiring as per the drawing.

No change of settings with the cartridge used.

Sounds great.
 
It's too damn fiddly to strap the two pairs of pins at the headshell end, thanks to the proximity of the sloping sides, so I take it you can just reverse things and strap the two pairs of pins at the cart end and just the one pair of pins at the headshell end, and obviously make the appropriate connections between cart and headshell to compensate for the reversal?
 
windhoek said:
It's too damn fiddly to strap the two pairs of pins at the headshell end, thanks to the proximity of the sloping sides, so I take it you can just reverse things and strap the two pairs of pins at the cart end and just the one pair of pins at the headshell end, and obviously make the appropriate connections between cart and headshell to compensate for the reversal?
Click to expand...

I am not the correct person to answer these questions. It took me a while to get my head around the connections and the diagram/drawing was my way of working it out. I am unable to remember the rationale for any of it.
 
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...

Strictly speaking, a mono button should *average* the L and R signals together. Not simply 'sum' them. And to do this correctly it generally means connecting together the two via a pair of resistors. This avoids annoying the source when, for example, L says "100mv" and the R says "No! -100mV" at the same time. Omitting the resistors can mean added distortion as the channels fight over who wins.

I confess I've wondered if blindly connecting stereo cart outputs also gives such problems. Anyone know of a report on that? As things are, NOT something I'd like to do with my cartridges when playing an LP. In addition to possible distortion generation it may also alter the compliance in the vertical.

So, personally I'd add a simply box to the pre-power link that does this as I feel is correct *if* you need it.
 
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