U47 clone : AMI or IOAudio +Aputis ? First build ! And capsule question, too...

[GeorgeToledo]

Questions, just for clarity...

What were the specs on the Peluso that you say sounds more like a real BV08? Was a real Neumann made BV08 measured at any point, for a reference? What are those specs? I would just like to understand better.

Why does the transformer pictured, stated to be an AMI, not have the AMI outer wrapper label on it? Is there a picture of the other side?

These Haufe/Grosser transformers are not for public sale?

At some point you wrote that the AMI doesn't have the chambers, but I know that is not the case. Since you didn't buy this transformer yourself, and it was from a friend are you sure it is an AMI?

When you reference the IOAudio transformers being better, what versions are you talking about of them? I am under the impression they are very small run, and have been made with many different lams.

Originally you made comment about testing many different subtypes of AMI transformers, or rather Andreas Grosser testing them(?), what were the specs on those if you still have them?

And all of this big test happened after your falling out at Oliver's forum... too bad more transformers weren't available, I personally hate having to patronize companies that I have felt burned by.

I'm not trying to nitpick, I just think that when someone makes statements that could be considered slanderous, that there is some burden of proof required. Especially when the one transformer was from a second party and on the other occasion tests were done by a second party, possibly able to be viewed as a competitor.

The inconsistencies and after the fact edits make it all hard to follow as well.

 

[ln76d]

Don't want to stir this up all over again, but what's with the constant references to people's English capabilities?

Not one person in this thread (except maybe ln76d!) could string together a sentence in Russian, never-mind write one down... But Misha, he's capable of writing perfectly coherent English. There's nothing he's said I haven't understood, and nothing I found offensive...

I'm sure we can all agree there's just no need to even go there...

Sorry Mike, you can't count on me here.
Cyrillic alphabet is like hieroglyphs for me

My opinion about Misha posts is also similar.
And i really don't think that Misha or anyone else here is against AMI and from any reason want to destroy reputation of company. Some people will like the product other not. Still Misha gave us more useful informations than we get from AMI.

 

[micaddict]

Better copy it while it lasts. 

 

[micaddict]

Well, I'd much prefer it if you don't delete anything.
But it's your call.

 

[micaddict]

Man, relax.
Seriously.
The whole world is not against you or out to provoke you.
Or Bonnie1 for that matter.
Let's have some fun here and please cut people some slack or benefit of the doubt.
Especially since transformers are not a matter of life and death.

But thanks for your useful info.
Serious again.
It is appreciated. 

 

[Banzai]

The inconsistencies and after the fact edits make it all hard to follow as well.

Just because you keep repeating something isn't going to make it true. His first post in this thread hasn't changed... If you'd have then focussed on reply #5 instead of trying so hard to discredit him, this entire discussion would have been unnecessary:

For o3misha, AMI transformers aren't the best choice when using an EF12, a VF14, or a VF14 FET substitute. He hasn't tried them with EF800's. Maybe they work better in that setup... Nothing more, nothing less.

The rest is about QC problems, of which AMI has more than others. A quick search of the forum will show you o3misha isn't alone...

----

Just to add something interesting to the conversation, here's a test of three T14 transformers, AMI vs. Cinemag vs. Haufe. I'll let you guys decide which is which. But goes to show, depending on what brand you choose, you'll end up with very different sounding microphones. Every person will have their own opinion on which is best... No point in arguing, it's entirely subjective.

 

[GeorgeToledo]

edit: not worth the time to discuss. Too many edits, too hard to keep track of versions of second hand info from Misha.

 

[Banzai]

ln76d posted Haufe was 'truly professional'... It's still there

And that banning you keep bringing up? He was basically bullied out of the forum for asking questions and lacking 'builder worship'... It was pathetic, and not something I'd go around proudly advertising.

The rest is painfully simple. You love AMI. He doesn't... The end.

 

[ln76d]

edit: not worth the time to discuss. Too many edits, too hard to keep track of versions of second hand info from Misha.

Man, finally!

Thanks

Just to add something interesting to the conversation, here's a test of three T14 transformers, AMI vs. Cinemag vs. Haufe. I'll let you guys decide which is which. But goes to show, depending on what brand you choose, you'll end up with very different sounding microphones. Every person will have their own opinion on which is best... No point in arguing, it's entirely subjective.

Can i guess?
Top:
-  left - AMI
- right - Haufe

Bottom - Cinemag

 

[Avgatzeblouz]

Ok everyone, as a newbie, I now have one more question : Regarding price, and sound, what are the differences from Poctop build over the MK-47 ?
Thanks.

 

[Pip]

Ok everyone, as a newbie, I now have one more question : Regarding price, and sound, what are the differences from Poctop build over the MK-47 ?
Thanks.

That is why we build them! You must listen for yourself.

I won't get into all the parameters that can make this happen. But my experience with all tube mics is that each one, even if they are the "exact same circuit" have their own little subtle variances. In this case those two mics are the same circuit but with different layouts. With the MK47 kit you get IOAudios transformer premounted to the PCB and Max's component choices, with Dany's you can use your choice of transformer and components. So their you are.

 

[Avgatzeblouz]

Thank you Pip ! Always very helpful.

 

[ln76d]

Ok everyone, as a newbie, I now have one more question : Regarding price, and sound, what are the differences from Poctop build over the MK-47 ?
Thanks.

Except things mentioned by Pip you also have to choose one tube vs. two tubes.
Personally i would try EF80/800 version - still didn't tried.
From my tests (f*ck you all which want any proof )  i had no luck with double and single 6028/408a with similar topology to U47 schematic. Good results i had with 10:1 transformer, but with 6.5:1 not especially.
Or maybe no PCB at all?
Doesn't tempting you look of original U47 guts?
It's not so hard to make
Then you could build two versions for comparison - for example two different plates - with one tube socket and the other with two. Potentialy you will need to double some parts if you will want to solder some directly on the sockets.
Also PSU will need to be more "universal" due too different heater voltages.
Still anyway you will have the options to use different tubes later - like EF12, EF13 or maybe someday you will have luck to find VF14
Someday i will try to use that crcuit with 6ak5/5654 - micaddict  gave me that idea, sending links to Dave Thomas mike!

http://harmoniccycle.com/hc/images/photos/U47/Neumann_U47_01a_md.jpg

 

[Avgatzeblouz]

Yes, the "real deal" point-to-point is tempting, but I lack knowledge... by a good margin ! That's why I'm leaning towards a kit. Even for the IOAudio kit, I will have a friend of mine building the PSU, and checking the mic after I soldered everything. I'm mostly into the sound itself, and he is mostly into electronics. Hope it will be a good match !

 

[Pip]

Ok everyone, as a newbie, I now have one more question : Regarding price, and sound, what are the differences from Poctop build over the MK-47 ?
Thanks.

Except things mentioned by Pip you also have to choose one tube vs. two tubes.
Personally i would try EF80/800 version - still didn't tried.
From my tests (f*ck you all which want any proof )  i had no luck with double and single 6028/408a with similar topology to U47 schematic. Good results i had with 10:1 transformer, but with 6.5:1 not especially.
Or maybe no PCB at all?
Doesn't tempting you look of original U47 guts?
It's not so hard to make
Then you could build two versions for comparison - for example two different plates - with one tube socket and the other with two. Potentialy you will need to double some parts if you will want to solder some directly on the sockets.
Also PSU will need to be more "universal" due too different heater voltages.
Still anyway you will have the options to use different tubes later - like EF12, EF13 or maybe someday you will have luck to find VF14
Someday i will try to use that crcuit with 6ak5/5654 - micaddict  gave me that idea, sending links to Dave Thomas mike!

Yes!

To clarify though Dany AKA Poctop offers two U47 inspired copy solutions. The D-47 and the D-EF47. My response was to the D-47 vs MK47, as they are basically the same thing each using the dual tube topologies. The D-EF47 would be IMO a totally different choice and I myself have never built an EF8X variant. But based on circuit and tube choice yes it is closer to an actual U47 in concept. The EF80 and following EF800 trace their lineage back to the VF14 they are also heralded by some to be the best available tube for this circuit. But this is only what i have read.

IN76D is correct that with the PTP solution experimenting becomes much more approachable. Also there is the 5693 tube which is is electronically an EF12.

 

[ln76d]

Sorry, sometimes confusing all these "clones" names
Am rather not a kit guy and barely read these threads.
Anyway, make point to point boards is nothing hard to make (or exciting - personally don't like any mechanical work).
Piece of good textolit, drill, scissors (best are the "butchery" for chicken bones), soldering connectors.
With the layout i personally (and probably some other guys) can help you.
Original U47 circuit is only 8 resistors, 3 capacitors, 1 transformer, 1 switch, 1 capsule, piece of wire. Transforme, output impedance, connection plate you can easily omit.

Btw. here's nice old thread on the other forum about tube substitutions if someone didn't read it.
Really great info, especially from Oliver (with no prove ).
http://www.neumann.com/forums/view.php?bn=neumann_archive&key=974359437&v=f

 

[afdobbert]

I went with an EF800 build for a few reasons, but one of the bigger things for me is that the dual 6028/408a tubes can be a pain to source, many are microphonic, ect. Personally, that configuration would add one too many layers of uncertainty for a first build. Also, someday I want to build one P2P with a 5693 tube. Those don't seem to get mentioned much but they are, as I understand it, quite similar to an EF12.

 

[ln76d]

I went with an EF800 build for a few reasons, but one of the bigger things for me is that the dual 6028/408a tubes can be a pain to source, many are microphonic, ect.

Did you ever tried 6028 or only read about microphonic effect in it?
I tried few different brands, in larger quantity Philips - none of it was microphonic...
Easy too find, pretty cheap for NOS.
Still in my opinion impedance is to high to use it with 6-7:1 transformers.
But "opinions" are divided

I was to lazy even to check and compare datasheets, also there's russian equivalent (don't remember currently - here's a middle of the night), but Henk probably remember
Still EF12 aren't so rare, maybe that's why i didn't bother.
Despite opinions about "proper" equivalents  - still i think that the  6AK5 could work good in U47 circuit.
5840/EF732 is submini version of it. I had good result with 6.5:1 transformer in other mike (i couldn't make more tests but i'll back to it, hope soon). Generally it's similar tube to 408a, but works much better in microphone circuits.

 

[afdobbert]

I went with an EF800 build for a few reasons, but one of the bigger things for me is that the dual 6028/408a tubes can be a pain to source, many are microphonic, ect.

Did you ever tried 6028 or only read about microphonic effect in it?
I tried few different brands, in larger quantity Philips - none of it was microphonic...
Easy too find, pretty cheap for NOS.
Still in my opinion impedance is to high to use it with 6-7:1 transformers.
But "opinions" are divided

I was to lazy even to check and compare datasheets, also there's russian equivalent (don't remember currently - here's a middle of the night), but Henk probably remember
Still EF12 aren't so rare, maybe that's why i didn't bother.
Despite opinions about "proper" equivalents  - still i think that the  6AK5 could work good in U47 circuit.
5840/EF732 is submini version of it. I had good result with 6.5:1 transformer in other mike (i couldn't make more tests but i'll back to it, hope soon). Generally it's similar tube to 408a, but works much better in microphone circuits.

I have not tried it myself, so certainly my comments should be taken with a grain of salt. I'm sure mics built with that circuit sound nice.

I'd love to hear the 6AK5 in that configuration, I love the sound of the LOMO 19a9.

 

[Bonnie1]

Hello Misha, In76d, Banzai and everyone else.
At the end of another 14+ hr work day (some of us don't have time hanging out on forums most of the day) I found this for you all to read, I think it may offer some answers.......... be sure to scroll down the page!
http://prorecordingworkshop.lefora.com/topic/3913166/Questions-Oliver-AMITAB-Funkenwerk-U47-body-kits?page=6#.V3sjDJMrJTY