Piston Ribbon Tuning (Beyer mics)

[12afael]

Hello, I have 2 M160 and one M260 that need new ribbons and I will try to repair them this weekend. I have done ribbons with normal corrugation for several mics but at this point I want to try the original piston ribbon used on those beyer mics.

I have a small rig that I intend to use to corrugate the ribbon. The original ribbon is stiffer than the 1.8u I have used on other ribbons I suspect it is 2.5u or thicker. Information about it is not clear.

I don´t know if the same principles apply for tuning piston ribbons. Someone have any idea of the frequency that those are tuned or the thickness? I have the impression that due to the minimal corrugation the frequency can´t be low as normal Full corrugated ribbons.

best regards
Rafael

 

[shabtek]

I have reribboned a beyer with zigzag corrugations and it 'worked' --I am not sure how differently from the original but it passed voice signal cleanly.

I believe Marik posted lots of info about beyer many years ago--he may even reribbon them--iirc he had pics and info on his site at one time.

I think the proper ribbon is formed by pressing in a suitable 2-part die;

there are longitudinal corrugations to give it rigidity and a few zigzag/perpendicular to length of ribbon on each end near the clamps

 

[12afael]

I re ribboned a M500 with normal zigzag and to me it sound fantastic but I have no point of comparison. I used 1.2u on that one.

I have read a lot of post here and some very usefuls from Marik and others. I took some ideas from his post to make a ribbon cutting tool with some precision I will post some pictures soon.

I designed and 3d printed a two part jig to produce the corrugation at the end of the ribbon. I tested it and seem to work fine. My current idea is to corrugate it in two steps. End corrugation first and longitudinal corrugations in a second step.

At the moment I have to come up with some idea for the longitudinal corrugation jig. I glued together 3 pieces of blades from a hobby knife of the correct lenght (14mm) that should give me the 3 longitudinal corrugations. It have to be done against something soft. I have some ideas but I have not tried yet with the "expensive" correct material. Ideally it should be a jig where I can control the depth of the corrugation but I think I will try free hand first. I have very good control of my hands so I hope I can do it if I use 2.5u.

It might be that those longitudinal corrugations needs to be applied one by one.

 

[12afael]

and here is the cutting tool. I need to add some springs for anti backlash but it work well. I did not design it for an specific precision but the long moving part should reduce the error. it have vernier on both sides and it use an M6 screw with .1mm pitch. with the graduated wheel every mark is .1mm. I think it can be improved a lot using different materials and machined instead of printed but I just do my own ribbons so I think it is good enough for the hobby.

 

[shabtek]

respect

 

[Marik]

Hello, I have 2 M160 and one M260 that need new ribbons and I will try to repair them this weekend. I have done ribbons with normal corrugation for several mics but at this point I want to try the original piston ribbon used on those beyer mics.

I have a small rig that I intend to use to corrugate the ribbon. The original ribbon is stiffer than the 1.8u I have used on other ribbons I suspect it is 2.5u or thicker. Information about it is not clear.

I don´t know if the same principles apply for tuning piston ribbons. Someone have any idea of the frequency that those are tuned or the thickness? I have the impression that due to the minimal corrugation the frequency can´t be low as normal Full corrugated ribbons.

best regards
Rafael

Rafael,

You don’t need to tune the piston (one of the beauties of this corrugation)—just lay it down, center in the gap and clamp down. Cool idea with the nails. You probably might need two pleats per side to make it more compliant. If you hear lack of low end—that will be an indication.

Best, M

 

[12afael]

thanks Marik! The Ribbons I have seems to have 1 pleat but it is hard to see and they were not in good shape

Well I failed in my first try and several others. The device I designed to cut the ribbon work BUT! it is really hard to hold the papers below and the papers (aluminum sandwiched in paper) needs to be pin down to the table or the drag of the blade will tear it. so even if I was able to do the corrugation the cuts were not consistent.

One of the things that make it difficult to keep the papers in position is that you have to adjust the tool to make the two cuts.  So I though that would be better to have a tool that already have the two cut adjusted. so you set the dimensions, put the tool over the papers hold it by hand or a toggle clamp and  try in normal papers to verify consistent cuts.

I´m designing the new tool. I plan to print it in the weekend. the main idea is that the rulers touch the paper all the time so just puting some hand pressure on them the cut can be made. It use M6 screws so the wheels are graduated in .1mm and it have holes for inserting a screwdriver or something if more precision is required. It use springs as anti backlash mechanism.

 

[shabtek]

drops of 90% alcohol can create temporary adhesion

 

[12afael]

you mean between the ribbon and the motor? probably something like 99.9% is better for noise.

 

[shabtek]

you mean between the ribbon and the motor? probably something like 99.9% is better for noise.

not only-- when handling, cutting, corrugating etc
https://groupdiy.com/index.php?topic=46378.0

 

[Matt Nolan]

or the drag of the blade will tear it

Perhaps a rotary blade like this would work better?

 

[shabtek]

is the guiding edge holding the aluminum/paper sandwich down firmly? are

I have always used a small ruler as a cutting guide. it provides surface area that may be an advantage over a thin edge

double edge shaving razors work well with the right angle.

alcohol might be helpful to get foil to stay with the glassine paper and to get material to lay nicely on a sheet of glass

 

[12afael]

is the guiding edge holding the aluminum/paper sandwich down firmly? are

I have always used a small ruler as a cutting guide. it provides surface area that may be an advantage over a thin edge

double edge shaving razors work well with the right angle.

that is the idea. keeping everything down under the guide.
I haven´t tried cutting it over a glass. that should reduce edge deformation. It might be necessary to keep a paper under the aluminum to get a better cut?

I have to experiment more with alcohol. I mean for ribbon making...  :

I printed the parts already. I will try to assemble it later.

 

[12afael]

I hope this work better. I will have to try it some other day.

 

[Whoops]

Hi Rafael,
did you have the chance to try your new cutting tool?

Any sucess with Re-Rebboning the Beyer mics?

 

[Nitrous]

any chance to get the .stl files?

 

[raketenmann]

Hey there
I just stumbled over this older threat and wanted to give you some information about piston beyer ribbons.
I have a pair of Beyer M320, that I want to reribbon. First, I contacted Beyerdynamic in Germany. They told me, that they don't service this mic anymore. All other Ribbon companies I know in Europe only do RCA-style zigzag ribbons. After a long search I found a post on Gearspace, that SAMAR Audio in the US can do piston beyer reribbon jobs. They say that they're using a special material that doesn't weak over the years. I am willing to send my ribbons over to the US to have the replacement done.

 

[Whoops]

After a long search I found a post on Gearspace, that SAMAR Audio in the US can do piston beyer reribbon jobs.

Samar Audio is member "Marik" that is in this thread.
They re-ribbon Beyer mics but last time I talked with Marik, they were doing it using standard ZigZag corrugation and not piston style.
I actually don't know anyone that is able to re-ribbon Beyer mics with the original Piston corrugation, no one is doing it.

I don't know about the M320 as it's an older microphone,
but for the M160 Beyer Dynamic sells the whole ribbon motor, and it was cheaper to buy a complete original motor for the M160 directly from Beyer than to send my mic to Samar for re-ribbon

 

[fum]

I reribbon a lot of Beyer mics. Good results can be had using a traditionally corrugated ribbon.

I had a stash of new old stock ribbons, but they only lasted a couple months.

The issue with the newer motors from Beyerdynamic for the M160 is that they use neodymium magnets, rather than alnico. If you already have the neo ribbon motor in your M160, you're all set, but if you'd like to keep your older microphone sounding as close to original, replacing the complete motor is not a good option.

Like many, I'm also working on a replacement ribbon. Mine is close, but still in the dialing in phase.

$.02

Jon

 

[raketenmann]

Samar Audio is member "Marik" that is in this thread.
They re-ribbon Beyer mics but last time I talked with Marik, they were doing it using standard ZigZag corrugation and not piston style.
I actually don't know anyone that is able to re-ribbon Beyer mics with the original Piston corrugation, no one is doing it.

I found out after reading some more posts - so well, probably he will reply and confirm, but this is information provided by him just recently.

I reribbon a lot of Beyer mics. Good results can be had using a traditionally corrugated ribbon.

I know that this is possible - but it is not the "original" thing, cause it just doesn't sound exactly the same. The piston ribbons are more rigid, you can leave the mics hanging over the drums for months without risk of ribbon sag. Also, the piston has more output and some better distortion measurements - but this is theory and I can't confirm from experiments, but that is how it is told.

I don't know about the M320 as it's an older microphone,
but for the M160 Beyer Dynamic sells the whole ribbon motor, and it was cheaper to buy a complete original motor for the M160 directly from Beyer than to send my mic to Samar for re-ribbon

AFAIN the ribbon motors in the beyer mics are pretty similar - at least the ribbon itself looks the same in the M160, M260 and M320 mics I saw. So it came to me as a surprise that Beyerdynamic told me, that they can't service the M320 anymore. If they replace the whole ribbon motor on a M160 rather than just replacing the ribbon, could it be that this whol assembly is done by a machine rather than a human? otherwise I really don't get it why they can't do that.

So sending the M320 to SAMAR is my only option for piston ribbon replacement.

I had a stash of new old stock ribbons, but they only lasted a couple months.

Yes, I understand that the material doesn't stand over time. In one of my M320 the ribbon is broken, but on the other, its not. No ribbon sag or anything, but the sound of the mic just sounds distorted. So to perform good, it definitely needs service.

Just out of interest: How will I know, what magnets my M160 do have? I have sort of pretty new ones, let's say from the 2000's or later. Would be interested to know....