Frequeently Asked Questions

  • F.A.Q.'s
  • Capsules
  • Amplifiers / Systems
  • Accessories & Parts

Q: Can I have a 'vintage' microphone I'm considering purchasing sent to TELEFUNKEN Elektroakustik for inspection?

A: Absolutely!! The cost for this kind of inspection is $125.00 USD. If any work is required we will notify everyone involved and can usually repair anything that might be wrong with the mic should you so desire.

Q: Can I purchase parts from TELEFUNKEN Elektroakustik for use in my historic microphones?

A: Of course you can!! However, unless you are recognized to us as an expert in the field of microphone repair, we will insist that you ship your system to our South Windsor, CT (USA) facility for the installation of those parts.

We will go over the microphone from top to bottom and get back to you with a repair / refurbishment quote prior to performing any work. The cost for the generation of a repair quote is $125.00 USD, which will be subtracted from your final invoice should you decide to have us perform the work.

Q: Can my original CK-12 capsule be re-skinned if needed? ...and what is the cost for this?

A: The original capsule can be "re-skinned" without a struggle. Shoot us an email or give us a call and we can get you a price.

Q: Can you reskin my original M-7 or KK-47 (Neumann) capsules?

A: If you have one that needs to be re-skinned, we can get that done for you without a hassle or undue delay, again give us a call and we can get you a price.

Q: Can only one diaphragm be replaced?

A: No, you have to have both replaced at the same time.

Q: What capsule is standard in the TELEFUNKEN Elektroakustik U-47 and U-48?

A: Both microphones come with a Mylar® "M-7" capsule. We do have PVC M-7 capsules available from our custom shop.

Q: What is the difference between Mylar® and PVC?

A: PVC was the material used in the original M-7 capsule that was designed by Georg Neumann in 1928. In 1958 Neumann GmbH switched from the use of PVC to Mylar as their diaphragm material of choice. Mylar is a less expensive material for the production of microphone capsules, and much easier to manipulate in the construction of the final capsule. It is a proven material that has been in use for over 50 years.

Some say that capsules made from PVC material have a better "depth" to the tone, an opulence that is unattainable from any other diaphragm material. This is why we have capsules that employ PVC diaphragms available.

It should be noted that many on the internet forums have commented that PVC will over time harden and crack. This is true, but it takes a good 30-40 years for this to happen (under normal conditions with normal use) and there is now a replacement source for the part so fear not!!

Q: What is the deal with the CK-13 capsule?

A: A while ago we identified a metal alloy used by the aerospace industry that is comprised of Aluminum and Titanium called "Alloy 2213". We had this alloy sputtered onto a Mylar backing and began to play around with it in our laboratory.

The properties of Alloy 2213 are such that the material is more rigid than the gold which is the traditional material sputtered onto the diaphragm backing material. It is also a lighter (as in weight) material so we thought the results might be rather interesting.

Over time we played with different tunings and tensions as the capsules were constructed and came out with what we thought was the optimal combination to achieve excellent frequency response and accurate sound reproduction. We hope you agree, but the only way to know if you do is to try one.

Q: I already have a current ELA M 25x [or C-12] microphone, can I install a CK-2213 capsule?

A: If you are working with an expert in the microphone field who TELEFUNKEN Elektroakustik recognizes as an expert, we will indeed be able to send that technician a capsule for installation, or you can send your microphone to us and we can retrofit a CK-2213 capsule, or you can purchase a fully assembled CK-2213 capsule assembly for your ELA M 25x [E or non-E] microphone [which will give you the ability to switch back and forth from "gold" to "Alloy 2213].

Q: What are the differences between the CK-12 and TK-12 capsules?

A: The CK-12 was originally remanufactured by TELEFUNKEN Elektroakustik to original historic specifications in early 2002. The cost to research and redevelop this capsule as a new product was high, due to the detailed manufacturing process surrounding the historic blueprints and guidelines.

The TK-12 and CK-12 share the same brass back plate and tensioned gold sputtered 10-micron Mylar diaphragm. Both capsules are hand assembled and hand tuned by the same process engineer in the TELEFUNKEN Elektroakustik lab in South Windsor, CT. Both are designed to sound exactly the same, with a smooth frequency response and a nice, airy presence boost just above 10kHz.

The CK-12 capsule is exact in that it's build process follows the original manufacturing process and includes parts and materials that are machined to the exact original specs and sizes created by AKG in 1947.

While the TK-12 capsule is an electronic (and more importantly, sonic!!) copy of the CK-12, we found that by using modern techniques and standard parts (molded plastics and assembly screws) we have been able to streamline the manufacturing process without compromising the rich (sexy?) tone of this highly critical part of our microphone system.


Q: What is a VF14K tube?

A: After considerable research, TELEFUNKEN Elektroakustik has located a glass tube originally manufactured for use in transoceanic telephone transmission (concurrently with the VF-14 which was mainly used in field and aircraft radio transmitter/receivers during WWII) that has remarkably similar properties.

This is not a Nuvistor, nor an EF86 tube, both of which have been previously used as substitutes for original VF14M's. While both of those will work, neither has the depth and richness of tone upon which we insist.

Carefully modifying the actual physical shape of the tube (by hand) we are able to place it inside the same metal enclosure, and with identical pin orientation, as the original VF14. The resulting sonic characteristics are extremely close to the original VF14M.

The TELEFUNKEN Elektroakustik VF14K comes with a 90 day warranty.

Q: What is the major difference between and AC-701 and 6072 version of the ELA M 25x and why does the ["non-E"] AC-701 version cost so much more than the ["E"] 6072 version?

A: The AC-701 and 6072 tubes run on entirely different voltages. In order to run the tube correctly the power supplies must be different. The price disparity comes from the "non standard" parts that go into the "non E" version.

The standard parts run across the ELA M 250/251 E & T microphones as well as the C-12. This affords us an "economy of scale" as we can order the parts in larger quantities, and pass the benefits of those parts savings on to you, the consumer. The "non E" version of the ELA M 250/251 is closer to a custom unit that is in production than an actual production product.

Q: Is it possible to modify my ELA M 251 E from a 6072 to AC701?

A: TELEFUNKEN Elektroakustik does NOT sell AC-701 tubes!! Our current stock is for production units only.

However, if you have your own tube, the price for modification can be easily calculated if you give us a call or zip us an email.

Q: Is there a package deal on the accessories (cable, psu, shockmount, box and case) if I buy the whole lot in combination with the service?

A: Unfortunately, everything is a la carte. You are already getting our best price so we will not "package" these products and services.

Q: What is the normal turnaround time for this kind of service?

A: We quote turnaround time as 3-4 weeks. Generally these kinds of projects are done in two weeks, but if we say 3-4 we know we will be safe and not late.

Q: Do you also make a plain cable without the swivel mount for an ELA M 25x mic?

A: That is not possible as there is only one connector housing for a 251. That housing is the swivel mount. This was the case with the original microphones and we have been historically accurate to a fault.

Q: Can I get a tweed case for my 'vintage' microphone?

A: Yep, no problem. See for details.

Q: Do you sell power supplies?

A: Absolutely, See for details.

Q: Can I get body parts [body tube] for my vintage U-47? C-12? ELA M 25x?

A: We can get you body parts for U-47 / U-48 mircophones but we have to install your serial number plate to the new body tube. We can ship ELA M 25x and 25x E body tubes [as the serial number for the microphone is housed in the plastic bits].

We can help you with a C-12 body tube but it will require an upfront deposit and an undeterminable wait for the body tube to show up as the serial number is engraved on the original and will need to be re-engraved. We will also need you to send in your original body tube before we ship your replacement so we can verify that you have the serial number you say you have [sorry for the lack of trust, but there are a lot of people that want to counterfeit "vintage" equipment and we will not be party to fraud].

Q: Can you help me with a dented head basket?

A: Yep, just call us.

Q: Do you have the plastic switch housing for an ELA M 25x mic?

A: Yep, just call us.

Q: I need ______ part for a vintage C-12 U-47/U-48 ELA M 25x, can I get it from TELEFUNKEN Elektroakustik?

A: Yes, we have that. From connector rings to body tubes to full refurbishments, we can do that. Call or email and we will ascertain the best way to proceed and get you pricing for that service.

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