Genuine Neumann versus Thiersch Capsules

[o3misha]

U47 was always a brighter MIC than a U87. From my experience, the U87 vocalists absolutely can't stand u47, they lack the density at the bottom of the spectrum, too airy and bright sound with a predominance of medium frequencies. In my opinion, you should pay attention to the type of AKGC12 microphone.

 

[MS Vienna]

As for the original capsule question - I own a bunch of the capsules in question so here are my impressions.

I recently bought a new Thiersch Blue line and I´m very pleased with it. Beautifully balanced and "right" sounding.
I never was happy with a red line Thiersch-reskinned vintage M7 in my UM57. Just has some weirdness to it. My all original vintage M7 in another UM57 head sounds just gorgeous (like my other original M7 capsules).
I own a vintage K49 that is clearly different from all the M7. Not in quality but in character.  It is generally darker and has a very distinctive and unique low mid heft that non of my M7 - old or new - has. Not better or worse, just more massive and weighty, can´t be simulated with EQ. Top end is slighty darker and velvety/smooth. It has excellent front/back matching and it´s in almost mint condition so I suppose it still sounds like when it was new - but supposing = speculating.
From o3misha´s statement it seems that recent K49 are quite different.
That said I personally find the M7 PVC sound most useful and mix-ready in a lot of recording situations.  But that´s just me and certainly a matter of taste. To cover various voices, a well balanced CK12-based ("brass", genuine) mic would make much sense to complement the M7 sound. Only then I would go for something K49-based.

As for PVC aging: 3 of my original M7 are way over 40years old and still sound great. No difference to my 1980s-90s UM70S microphones (fantastic workhorses btw). So in deciding between blue line or red line Thiersch capsules I would not worry about aging too much. 
I´m really satisfied with my brand new Thiersch capsule and assuming my specimen is representative I would not hesitate to order another one when needed.

Of course a DIY-mic built skillfully from scratch to original specs could equal the quality of a vintage original if the right ingredients and methods are used. Not easy though. I have never bought a premanufactured commercial DIY assembly kit.

 

[abbey road d enfer]

I recently bought a new Thiersch Blue line and I´m very pleased with it.

Why? Did you simply needed more mics, or were you looking for something in particular?

Beautifully balanced and "right" sounding.

What do you mean by "right"? Do you mean right in itself, or right in comparison/ similar to a reference?

I own a vintage K49 that is clearly different from all the M7. Not in quality but in character.  It is generally darker and has a very distinctive and unique low mid heft that non of my M7 - old or new - has.

A trait that can be found in modern incarnations such as M149 and TLM49.

Not better or worse, just more massive and weighty, can´t be simulated with EQ.

I'm always suspicious of that type of comment. Response of condenser mics is a (very) damped 2nd-order resonator over a range that extends to about 4kHz. Whatever response anomalies in that frequency range are normally EQ-able with a run-of-the-mill parametric EQ.
I agree that HF response is more difficult to EQ, since it is the result of several factors: reflections and secondary resonances (diaphragm break-up) and diffraction. The latter is easy to EQ with a parametric, although most mic manufacturers choose to EQ it with a low-pass filter, since the diffraction effect happens in the upper octave; reflections are the most difficult to EQ because they require non-minimum-phase filters (if one is nitpicking).
What is definitely impossible to EQ is the directivity and response to distance; that's what users and surveyors of the Slate VMS system have observed. Townsend Labs have demonstrated that, in order to provide a convincing simulation, the sonic field must be reconstructed as well as the frequency response.

From o3misha´s statement it seems that recent K49 are quite different.

And that's how it's gotta be, since the current K49 is Mylar instead of PVC. However, most of the character, being related to the mechanical construction, is preserved.

As for PVC aging: 3 of my original M7 are way over 40years old and still sound great. No difference to my 1980s-90s UM70S microphones (fantastic workhorses btw). So in deciding between blue line or red line Thiersch capsules I would not worry about aging too much. 

That is true as far as the mic is stored in a controlled environment. PVC is sensitive to humidity; in order to retain its original mechanical properties, it must be stored in an environment compatible with organic life, about 20°C and 70% humidity.

 

[o3misha]

If the temperature inside the mic is high ( like in U47 or higher) PVC may  die much faster than in any other mic. If it works in UM57 or Gefell umt70 it never gets too much heat from the amplifire. As for sound of Thiersch M7 BLUE: it sounds very close to Geffell/Neumann capsules because of PVC material but it gives a bit different response because of different type of PVC material ( different method of manufacture, more modern) and different thickness of membranes. Old Gefell~10-12 microns, new Thiersch~8micron. Never tested old K47, but new K49 sounds much more bright than any m7. You may hear it in m149 tube mic.

 

[MS Vienna]

... heat from the amplifire.

I do like that pun
Thanks Misha for the insight.

abbey road d enfer,
I bought the Thiersch capsule because I frequently read good things about it and was curious about the actual sound. Similar to OP. 

 

[MS Vienna]

About "right" sounding: To my ears it captures the essence of the sound source well and in a way that´s pleasing to me.  I like what I hear.  But try and hear yourself.

 

[noulou]

Last week i completed a build with a blue thiersch, aputis body, ef802 oliver circuit and moby bv8.
Sounds insanely good next to a mint, genuine u48 (all original parts) with a neumann k-47.
Most people would say better i think.

 

[useme2305]

noulou, is andrew finally shipping out U47 bodies again or is this a body you had laying around for a few years?

 

[noulou]

noulou, is andrew finally shipping out U47 bodies again or is this a body you had laying around for a few years?

Got it  from someone else on the forum

 

[rmburrow]

K49 ( Neumann , new) - more highs after 10 kHz than any m7,  less body (200-400Hz), a bit too much ( except good VF14) 2kHz.
Thiersh M7 Red = just fine, not equal to earlier Gefell/Neumann in color of high freq-s.
IMHO, it works better with higher feeding voltage~70-75VDC,
Thiersh Blue M7 less highs after 8 Hz,then Red , a bit more presence (5-6 kHz).
Gefell (new)  : less low end than all others,
Gefell/Neumann old - just fine, with right Neumann-ish color in highes and presence.
The best choice fore M7 sound- Red Thiersh ( most reliable capsule)

Be careful about the polarizing voltage on the capsule.  75 volts sounds high; normal polarizing voltage is in the 40 to 60 volt range (dependent on the capsule).  The membrane and back plate are closely spaced and there is an electrostatic force between the membrane and back plate.  You don't need membrane collapse or arcing within the capsule, which will destroy the integrity of the membrane.

Look at the mic schematic; some of the mics contain a resistor voltage divider to obtain polarizing voltage off HT; other ones derive polarizing voltage from the cathode (elevated above ground).

 

[o3misha]

Modern Thiersch capsules and Neumann K49 capsules may work fine at 80 VDC. Who told that 60 VDC is maximum? For old aged capsules - yes, 50-60 VDC is ok. But with new Thiersch capsules 70-80 VDC is normal. I checked it with Andreas Grosser. I checked in my personal mics- all is fine, no problem.

 

[Moby]

Last week i completed a build with a blue thiersch, aputis body, ef802 oliver circuit and moby bv8.
Sounds insanely good next to a mint, genuine u48 (all original parts) with a neumann k-47.
Most people would say better i think.

Great: ) please let me know what version of lamination you used? Ni78 or mix with Ni49?

 

[panman]

.And that's how it's gotta be, since the current K49 is Mylar instead of PVC. However, most of the character, being related to the mechanical construction, is preserved.

K49 has always been Mylar and never PVC. The reason the K49 replaced M7 is that neumann wanted to get rid of PVC and its drawbacks.

 

[Pip]

IMO. I prefer the M7 variant to the K49 variant but that is me! In my experience with other engineers and producers they like the K49 it is brighter and to my ear faster (better transient response) and is a more "modern" sound so  therefore more appropriate for today's music market. But just another voice in the crowd.

Also that is one hefty price tag for the K49 ouch!

https://spares.sennheiser.co.uk/neumann/neumann-m-149/neumann-k49-capsule-for-m149-microphone-053291.html

 

[vocals07]

Well I’ll tell you this, I’ve had a lot of experience with capsules and I found that the capsule contributes most of the sound of the mic. With that said I e found the Thiersch is absolutely amazing he even bought the original machines from Neumann. But as the other guy said also you do need an original Haufe transformer and the original tube. You can however come very close without the original tube but it won’t be the same.

 

[xeawr]

K49 has always been Mylar and never PVC. The reason the K49 replaced M7 is that neumann wanted to get rid of PVC and its drawbacks.

Any idea what those "drawbacks" could be (apart from aging faster)?

 

[emrr]

K49 has always been Mylar and never PVC. The reason the K49 replaced M7 is that neumann wanted to get rid of PVC and its drawbacks.

There's a document from the 1960's detailing the fact that any U47 returned for service of any type would have the capsule replaced with a K49 as a matter of course, so that tells us how quickly Neumann decided it was an issue that needed to be addressed.  Of course I have a Thiersch Blue in a clone.....and a UMT70S from 1998 that's fine so far. 

 

[xeawr]

well I do ask partially because I have four UM70S microphones, all with PVC capsules obviously. I find them to sound nothing less than AWESOME, but I do wonder, why Neumann so quickly left that route.

And btw, it's not like MG is "swimming" in them. Most of their mics have PET capsules. Just the UM92, UM900 and UMT70S and their cardioid-only counterparts have the PVC capsule. Besides, they seem to have a noticable lead time for capsules, maybe because demand is high or - what I would guess - PVC capsules are a niche in the microphone market, and manufacturing the PVC film (and capsules) is a laborious enterprise.

Even Thiersch had at some point "given up" on the PVC until their comeback in recent decades. Would be worth chatting with him about those "drawbacks"...

For now, let's hope my mics continue to give me outstanding results...

 

[Moby]

Well I’ll tell you this, I’ve had a lot of experience with capsules and I found that the capsule contributes most of the sound of the mic. With that said I e found the Thiersch is absolutely amazing he even bought the original machines from Neumann. But as the other guy said also you do need an original Haufe transformer and the original tube. You can however come very close without the original tube but it won’t be the same.

True that capsule makes the most important sound impact but Thierch  doesnt sound like the original Neumann - Gefell  M7. It sounds ok but not the same.  Even good mylar reskin of the vintage capsule sounds better than any of M7 replica.  BTW  who told you that Haufe Bv.08 is the original transformer? Sorry, thats not true. Neumann did it in house.

 

[AusTex64]

Oliver Archut RIP used the Thiersch Blue PVC capsule in the Lucas CS-4. I built one from an AMI kit, sounds fantastic. I later swapped in a genuine Neumann K49. The K49 is smoother in the midrange and has more HF extension. However, I’m still not sure if I like it more than the Thiersch. Need to build another CS-4 and put the Thiersch PVC M7 in and directly compare the two. They are both good sounds, don’t think you’ll be disappointed either way you go.

For your first mic, might want to try the made in China /skinned in Germany K47 that AMI sells with their kit. Once the mic is built and you gain confidence handling capsules, maybe try something more expensive/exotic. I keep a nice supply of nitrile gloves around when handling capsules and 1G resistors.

One more tip - mount all the components up off the PCB enough to clean under them later if necessary. Just in case you contaminate something during assembly. I’ve built and repaired a lot of gear and mics require extra PITA care.