MK67 - new U67 clone coming up

[ruairioflaherty]

Excellent Max.  Any timeline on the TLM67 conversion version?

 

[ioaudio]

Unfortunately there was a data mishap with the Pcb so the TLM/87 conversion will take a little longer.
The syt-5 body version is finished and I'll pass over to Chunger who will create one of his perfect build documentations for it.

 

[Category 5]

As usual I already have  a crew of friends really interested in this next project Max.

I especially love how the configuration mimics that of the original U67 but noticed you are using polyester caps throughout and I'm pretty sure the originals (at least some) were using polystyrene.  Any reason you went with polyester?

Risk of overheating?  too hard to source?  Did some originals do the same?

Also, you mention the SYT5 "version".  Are other versions planned?  (like maybe a custom body kit like the MK-U47)?

Like your last kits I don't think these will sit around long.  Thanks again for doing these!

 

[ioaudio]

There's only two Polstyrene/Styroflex Caps in the U67: the 500pF in the switching section and the ~100pF in the feedback around the transformer - I use Styroflex in the for these positions too.
Additionally there will be a conversion for TLM67/U87 users, check earlier in the thread.

Some more pics from the SYT5 version:

 

[Category 5]

yeah. I went back and searched for some pictures and it looks like both the original and the re-issue had polyester where you do as well.  Not sure where I got that they were all styrene.  Thanks for the new pics.  It looks absolutely killer.

 

[Category 5]

BTW - Enough room in there for an E80F?  It looks like it from the pics but before I start bidding I thought I'd better ask.

 

[ioaudio]

Yes longer tubes are no problem, plenty of space.

 

[Melodeath00]

I can't see where the capsule is sitting in the headbasket, but will there be a way to raise it up a bit? Looking great

 

[ruairioflaherty]

Unfortunately there was a data mishap with the Pcb so the TLM/87 conversion will take a little longer.
The syt-5 body version is finished and I'll pass over to Chunger who will create one of his perfect build documentations for it.

Bummer on the corruption.  No rush for me Max, just trying to make some rough plans.

Cheers,
Ruairi

 

[ioaudio]

I can't see where the capsule is sitting in the headbasket, but will there be a way to raise it up a bit? Looking great

That shouldn't be too difficult.

>>No rush for me Max, just trying to make some rough plans.

i just received a mint tlm67, so i'll verify measurements and order the pcb.

-Max

 

[chunger]

Raising the capsule shouldn't be a difficult process, and there are several simple options:

1) use any shim material and drill 2 holes .  . . (acrylic, brass, etc.).  Place the shim under the capsule mount and  replace the capsule mount screws with longer M2 screws (12mm length would work well).

2) use 2 standoffs under the capsule mount and use longer screws (not so pretty, but 100% functional)

3) re-drill the base for previous style mount and use 8mm height M3 standoff on the post.

I have used option 3 for a build, and it worked out pretty well in a U87 test mic on the Gen 2 SYT-5 body.

Looking forward to getting this project on the bench and letting folks have an in-depth builder's view of it.

 

[Category 5]

Genuine Neumann capsule on the way for this project.  What are some of you other guys planning on using?

Heiserman?  Known for great K67s, huh?

Shannon Rhoades of Mic Rehab?  Seems to be a capsule ninja of sorts.

Chinese K67s?  Cheap enough to buy a half dozen and cherry pick.

Chinese K67 re-skinned by your favorite master?

Curious since I wanted to do a pair but think I'm not rich enough for another genuine Neumann capsule.

Max, will there be a passive PCB for the PSU or just retrofit the stock Chinese supply?  Matador's new universal supply would be a good chloice, but since it's regulated it will sound different from the original design.  I think the C12 supply could be tweaked for 210V.

 

[chefducuisine]

I've been through this: In the end the best option for capsules in a U67 is to go with the original.
Second best Option: Check ebay for a used one but be prepared to invest another 100 bucks for reskinnig and be carefull to whom you send the capsule to...

All the other capsules are somewhere in the ballpark. Some more than others. To me this is a bit of gambling that doesn't fit if you really wan't to built a mic in the region a U67 belongs to.

Reskinnig a chinese capsule isn't an option - HQ manufacturing includes a precise manufacturing of the backplates as well as some treatment. There even is a difference in drilling the holes in the backplate. You will be closer to an original, but still not there.

There is a lot of rubbish on the net when it comes to capsule improvement mostly written by some self promoting gurus - take it with a grain of salt.

For the PS: Keep in mind that a U67 needs negative 6.3V for the heater. I am not shure if any of the mentioned Kits or PCBs are capable of this.
Edit: I just have seen Chungers one takes care of this http://groupdiy.com/index.php?topic=55333.0

 

[ioaudio]

As already explained before, the original's heater supply IS regulated, B+ is passive.
Of course my modification for the supply takes the negative voltage for heater into account, and it's B+ is passive like the original.
It works/sounds just like the original.

-Max

 

[dmp]

I have a Beezneez capsule and it's very good.
Another member here compared the Beezneez and Neumann:

http://groupdiy.com/index.php?topic=57167.msg728815#msg728815

 

[ioaudio]

First batch of kits is on the way to 'Chung.

 

[Melodeath00]

First batch of kits is on the way to 'Chung.

So just to clarify, are these going to be sold in chunger's shop? Do you know the price? Will we need anything separate besides tube and capsule? Thanks

 

[ioaudio]

Yes, one-stop shopping at Chungers!
Not sure what will be included in the package and how much it will be, but i expect some news soon.

 

[Category 5]

For those of you gearing up for the 67 project here is a good source for inexpensive NOS e80f tubes

http://www.ebay.com/itm/1x-E80F-PHILIPS-Pentode-Gold-Pin-S-Q-Tubes-6084-CV2729-/310983061874?pt=Vintage_Electronics_R2&hash=item486808f172

This is one of the best tubes for use in a 67, even though everyone digs for the Telefunken EF86.  These are premium, gold pin tubes and are super in a 67.

I also got a very good price on a new K870/K67 genuine capsule for those wanting to go premium, and he has mentioned that he can get more (both new and re-skinned originals) and would be open to doing a group buy if enough people are interested.  The K870s are over $1000 from Sennheiser now and this guy is already about 35% cheaper.

Eric's capsules would probably be one of the next best choices, so I'm planning to build one with each, but I thought I'd drop the note before everyone starts getting parts ordered because original capsules will definitely be best, and unless you get warm and fuzzy by seeing a diamond on the bottom of your tube the option I posted above is a better one.

Thanks to Max for another super looking kit.  I can't wait to smell flux.

 

[Melodeath00]

For those of you gearing up for the 67 project here is a good source for inexpensive NOS e80f tubes

http://www.ebay.com/itm/1x-E80F-PHILIPS-Pentode-Gold-Pin-S-Q-Tubes-6084-CV2729-/310983061874?pt=Vintage_Electronics_R2&hash=item486808f172

This is one of the best tubes for use in a 67, even though everyone digs for the Telefunken EF86.  These are premium, gold pin tubes and are super in a 67.

I also got a very good price on a new K870/K67 genuine capsule for those wanting to go premium, and he has mentioned that he can get more (both new and re-skinned originals) and would be open to doing a group buy if enough people are interested.  The K870s are over $1000 from Sennheiser now and this guy is already about 35% cheaper.

Eric's capsules would probably be one of the next best choices, so I'm planning to build one with each, but I thought I'd drop the note before everyone starts getting parts ordered because original capsules will definitely be best, and unless you get warm and fuzzy by seeing a diamond on the bottom of your tube the option I posted above is a better one.

Thanks to Max for another super looking kit.  I can't wait to smell flux.

?? A new K67 from Sennheiser is about $550. Are you in the USA?