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

[Pip]

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.

Just to clarify a 6028 is a 408a they are the same tube. As is the EF95/6AK5 all be it with a different filament voltage. The 408a has a 20V filament where as the EF95/6AK5 is at 6.3V, Granted there are different manufacturers which of course leads us to the usual black plate vs silver plate large plate vs small plate etc....  I myself have done enough research where I feel the USA WE408a tube is better then its European manufactured counterpart!  But as far as I know this is not like the difference between a 12AY7 and a 6072 where one is a low noise variant even though they are essentially the same device. I am willing to be educated more if mistaken. The 6028/408a/TS62 are one and the same tube. Are there slight variables? I am sure there must be but these tubes are all basically the same.

I love the 5840 tube it is one of my favorites. I have been using them and testing them for over 10 years in mics. An article years ago by David Royer hipped me to this tube.

The 5693/6SJ7/6ZH8 is also a good tube and has the exact same properties as an EF12 but most importantly uses the easier to source octal tube socket as opposed to the far more expensive and hard to source TUS-Y8-G socket of which the only new ones that I am aware of, and they are OK, come from Asia.

Yes I agree that you have to listen and test a lot of tubes before you get to the ones that are mic grade with 408a tubes. You can read my posts about the searches. But that is the same for any tube really electronic soundness and microphone grade are not one and the same.

 

[Bonnie1]

Yes, very good Dennis,  I did measure this transformer not once but 10 times, beleave me, trying to get 150 H inductance. The result I got from Andreas in Berlin -111H , Later I got freq response- very leaner, as you can see. So, the problemof sound difference was not bad freq response. It was something else. I propose to discuss in PRW.  Guys asked me  how I measured inductance and I replied that a special device. Oliver told me that the device needed some very specific, L- meter should can measure metal core... I did not know what he means. As far as was not in Berlin already,  then I made myself a diagram of the measurement using a computer program and a simple chain of resistors with a capacitor and measured and ( tried to measure the inductance.) Yes I have the required 150 H and hastened to declare this to the  PRW. Unfortunately, I was wrong. My method contained the error. Andreas explained to me later , but since I was banned , I didn't report a damn. That's the whole story. The measurements that I'm posted here correct, it was made in Berlin, because the device have Andreas just right.

How many more different stories are people going to hear from you?  At this point you have presented yourself as incredible.
Furthermore you say that you want to learn, you have taken the completely wrong approach for busy professionals to take the time and help you.
In an earlier post, I told you I would provide some measurements etc... and I still intent to for educational purposes.  I myself am not an electronics guru, so I try to be silent so I can learn from those that are.  Indeed Oliver was one the greats, and I feel blessed to have spent so much time with him!
I really don't care what comment follows.... there is the absolute Truth,  and then there's something entirely different!

 

[GeorgeToledo]

I love the 5840 tube it is one of my favorites. I have been using them and testing them for over 10 years in mics. An article years ago by David Royer hipped me to this tube.

(walking past the debris)

I have really enjoyed the 5840 equipped UM17 mics that Oliver Archut put together - a point to point build and a couple PCB ones. 

I've had opportunity to use them directly next to other quasi U47 circuits, and to me they hold up very well. There might be some logistic and historical reasons why the EF12, UF14, EF80/800, etc., are considered upmarket tubes compared to the submini... and I get it, but sonically, I quite enjoy the 5840.

I'd be very curious to hear it right next to the real deal, at the same time. Hopefully this lifetime.

 

[Pip]

I just commented PRW dialog. Nothing new from me. I do not understand you, honestly. What struck you most? I just explained what happened in more detail. Explained my purpose. you think that I discredir Oliver. I have to give answers, because it's not true. As for professianals: I have another expert in Europe, who has " time" to help.

Ok so it's done then.. Is it over?

The now use of yet another person of note that to say the least has an opinion. The venerable and honorable proprietor of German Master Works.  Has caused me to feel a need to yet again try to bring in an outside perspective.

I have to say that I think this has been a learning experience on a lot of levels. I feel I need to say something I have said before. While all concerned that have been brought to the fore as professional experts, both with us and departed. Both for and against. There is no doubt in my mind they are/were legends in the Neumann restoration and after-market world. Some have even brought their level of technical expertise and knowledge to new products all of which are reliable and storied.

That said there is one tragic flaw they all suffer from, yet, at the same time it is why they have all been so influential and pervasive. They are all obsessive! I mean they are really passionate about this stuff. They all have strong opinions and their work reflects that. But with that said. Their work is storied and tangible and documented and they have all put their butts and their time and money out there. So yes when they hear a contradicting opinion they respond in maybe not the healthiest and wholesome of ways even to each other. No it is not right and no it may be hurtful at times. But the individual(s) that feel they have been wronged have two choices! Embark down the road of I WILL SHOW THEM or take the far more expedient yet difficult path of self-examination and brutal self-honesty and after doing so see if if they can grow from it and get better themselves. Because my experience is that all Gurus self-prophecy-ed or exalted are seldom wrong, ask them!!!

 

[Banzai]

At the end of another 14+ hr work day (some of us don't have time hanging out on forums most of the day)

Some more friendly advice: drop the condescension. It's not now, and won't ever do you any favours.

 

[GeorgeToledo]

At the end of another 14+ hr work day (some of us don't have time hanging out on forums most of the day)

Some more friendly advice: drop the condescension. It's not now, and won't ever do you any favours.

Honestly, many of your posts to me in this thread have been quite condescending.... after saying I have some opinion, you go "oh did you really ever hear that?". I mean what the hell? Condescending.

Dennis is describing a reality, not being condescending. It's hard to keep up with this kind of crap on an internet forum if life has handed you a very busy day.

 

[Banzai]

Honestly, many of your posts to me in this thread have been quite condescending.... after saying I have some opinion, you go "oh did you really ever hear that?". I mean what the hell? Condescending.

Dennis is describing a reality, not being condescending. It's hard to keep up with this kind of crap on an internet forum if life has handed you a very busy day.

I'm not getting into this with you. Think what you like, I really don't care... Unlike Dennis the busy professional, I have a full day of free-loading and doing nothing to get back to...

 

[ln76d]

Just to clarify a 6028 is a 408a they are the same tube. As is the EF95/6AK5 all be it with a different filament voltage. The 408a has a 20V filament where as the EF95/6AK5 is at 6.3V, Granted there are different manufacturers which of course leads us to the usual black plate vs silver plate large plate vs small plate etc....  I myself have done enough research where I feel the USA WE408a tube is better then its European manufactured counterpart!  But as far as I know this is not like the difference between a 12AY7 and a 6072 where one is a low noise variant even though they are essentially the same device. I am willing to be educated more if mistaken. The 6028/408a/TS62 are one and the same tube. Are there slight variables? I am sure there must be but these tubes are all basically the same.

I love the 5840 tube it is one of my favorites. I have been using them and testing them for over 10 years in mics. An article years ago by David Royer hipped me to this tube.

The 5693/6SJ7/6ZH8 is also a good tube and has the exact same properties as an EF12 but most importantly uses the easier to source octal tube socket as opposed to the far more expensive and hard to source TUS-Y8-G socket of which the only new ones that I am aware of, and they are OK, come from Asia.

Yes I agree that you have to listen and test a lot of tubes before you get to the ones that are mic grade with 408a tubes. You can read my posts about the searches. But that is the same for any tube really electronic soundness and microphone grade are not one and the same.

Sometimes i use the names interchangeably, yes these are the same and of course can vary a little due to manufacturer.
As noticed (this wasn't in U47 circuit) that i get really similar difference between WE and Philips, when i changed Philips with another Philips Overall it wasn't difference like night and day. Maybe it's much more related to the single tube parameters but probably strong depend on the topology,
With U47 circuit type with one 6028/408a i gave up really quick. Then i designed my "S16" microphone also with one - it was pain in the ass  to get satisfiing result. Anyway microhone sounds really good, also tried 5654/6AK5 in this circuit and it sounded little bit better (still probably difference in impedance). After all, for fun i tried two 6028 in U47 type circuit. And still effect was similar to the one tube. So i gave up on 6028/408a except S16.
Anyway none of the tubes i had, have any problem with microphonics or wasn't suitable for microphone use. Each was really clean and differences were really small. Definately not difference like for example various 12ax7 in hi-gain guitar amp.
BTW. by U47 circuit i have in mind topology only and capsule - am not making clone, not using any BV08, using various donor bodies. Not even trying  to catch U47 sound.
For the real clone i think i have time - still waiting for good looking body which is cheaper than Flea - waiting for Aputis "next generation" of bodies
Currently i have stock of really great 5654 that's why am thinking about back to U47 topology.
Anyway still in queue i have two other circuits with this tube - it's truly impressive and easy to work with tube.
Yes, it's 6.3V filament, so it have to be used in similar cathode arrangement to the EF80/800. Dave Thomas also make it that way.

 

[ln76d]

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

No one requires from you to hang all the time on the forum. Instead make great job for AMI (hope there would be some new products in some time), concentrate on what's most important! Personally i keep fingers crossed for AMI, i was really afraid that when Oliver passed away, company will not survive. But as we can see, it goes in a good way.
You know, we "keyboard experts" have nothing to do with the time. Despite that i registered few years later than i started my adventure with gdiy, that i was absent for long time here, due to many responsibilities - we still are here from passion or all related needs.  Oliver, despite his company and products, also loved to talk about the gear! He also freely share his opinions, many never proved, but usual no one fight with him about that. Agree, not agree - who cares.

Why you are here?

I don't see similar approach, rather tryings to fight with some virtual problem, trying to catch someone  "mistakes", prove something - but for now i still don't know what - because pointing out Misha previous words, you will not prove anything what's related to the AMI BV08. Even if Misha, or his measurements are wrong, still doesn't prove anything what's related to the AMI transformer.  He have right to make mistakes, but he search the answers - what's most important. Reall profesionalist should help to find the answers.

But for know this everything is really pointless. Another gearslutz story...

If you are so busy, then please take your time, and please back to us with some meritorical, technical related arguments.
We will be here still and we will be waiting with open arms

 

[ln76d]

At the end of another 14+ hr work day (some of us don't have time hanging out on forums most of the day)

Some more friendly advice: drop the condescension. It's not now, and won't ever do you any favours.

Honestly, many of your posts to me in this thread have been quite condescending.... after saying I have some opinion, you go "oh did you really ever hear that?". I mean what the hell? Condescending.

Dennis is describing a reality, not being condescending. It's hard to keep up with this kind of crap on an internet forum if life has handed you a very busy day.

George,  i also asked the same way afdobbert about microphonic in 6028 tubes.
But truly in good intensions, and truly didn't want to be mean.
Over the years on many forum were created some "urban legends", it's good to keep things straight, am a huge fan of testing everything and I recommend to first check by yourself.

 

[GeorgeToledo]

Over the years on many forum were created some "urban legends", it's good to keep things straight, am a huge fan of testing everything and I recommend to first check by yourself.

Yeah just like has happened with Misha... bunch of secondhand stories, initially told firsthand.

By the way...Hey I won a Grammy! Oh wait, that wasn't me, it is just people I've worked with. Same thing right!?

I don't know about you all, but whenever I have had a problem with a manufacturer, I contact them, and attempt to get it sorted out behind the scenes, not start immediately shit-posting on an internet forum. Whether it's a legitimate mistake on the company's part, or a mistake on the user part....either way can lead to heated discussions like this, with a low signal to noise ratio.

As a matter of fact, I have had a issue with a product from a manufacturer that often posts on the forum here (not AMI), but I'm not here throwing muck. I'm having communication about it, and getting it sorted out. Like you would do when you consider people human beings. Since one of Misha's stories where he bought a transformer wound up being his friend in the end (OK), I guess it wasn't their place to have that sort of communication. That makes the choose your own version stories from Misha even more outlandish.

AMI is a real company that has made countless good sounding gear. Misha is a guy who bitches on the internet about AMI in the vast majority of posts, for years. So many years that he forgets that he originally told the story entirely different ways. There have even been *a few* versions just within the context of this thread, obscured by edits after the fact.

As far as you go ln76d, I have to say that I like the Gallifrey tag!  8)

 

[o3misha]

Toledo, I'm really tired. I'm never vilified - enough to lie!!! I was asking questions on the forums after months could not wait for a response from Oliver, and AMI, damn it. I spent a lot of money on stupid transformers and still can't understand where they made the mistake why these AMIs do not sound as they promise. And what did I get in return? A lot of accusations from people like you , a bunch of insults. All, I've had enough. I'm never gonna fall for this bait. if some one need my advice I will send the person in personal correspondence.  All hail AMI!!!
If I publish the information with someone else's words,it was not  not anyhow , but the best expert in Europe. He will never participate in forums like PRW because he does not need. Neither to promote your business as some others, nor for useless disputes. I trust his words much more, than a strange, troubled the visitors of the forums, like PRW. I'm not talking about Oliver, of course. If you personally have doubts about the veracity of my words -I'll give you personally the contacts of Andreas. He can confirm that my words - true.
PS: As I promised, all my post, except important info are deleted. Trolls - you had the upper hand again, congratulations. Bye!

 

[AusTex64]

Wow, what a string. 

To the OP, I'll bet any of the transformers mentioned - AMI, Haufe, IO Audio won't SUCK. Will they all sound a bit different? Likely. But then again, how much? We are a nitpicky bunch here (from what I've seen). Not a bad thing, the devil's in the details. But in the grand scheme of things, with tube mics the sound is most dependent on (in order) - capsule, transformer, tube. Some people are very concerned with coupling caps, metal film vs. carbon comp resistors, etc.  But I'll bet if you get a great capsule, one of the aforementioned transformers and enough tubes of the type you choose to use to find a quiet, non microphonic one (not a trivial task), you'll be rewarded with a great tool to record music with. And isn't that what it's all about?

 

[micaddict]

 

[ioaudio]

Regarding the Chambers of the Bv.08/Bv.11

I received a few emails regarding the winding technique of the original Bv.08/Bv.11.

Besides the lamination core type, size and resulting inductance which have been discussed at
length, there is another unique feature in the construction of the Bv.08/Bv.11,
the chambered winding technique.

In order to extend the Freq. resp. in the top, each of the two bobbins/coils per transformer
are divided in 4 seperate sections resulting in 8 chambers total.

Neumann specified this bobbin:

4 coils during rewinding a 50Ohm version

-Max

 

[ln76d]

Wow, what a string. 

To the OP, I'll bet any of the transformers mentioned - AMI, Haufe, IO Audio won't SUCK. Will they all sound a bit different? Likely. But then again, how much? We are a nitpicky bunch here (from what I've seen). Not a bad thing, the devil's in the details. But in the grand scheme of things, with tube mics the sound is most dependent on (in order) - capsule, transformer, tube. Some people are very concerned with coupling caps, metal film vs. carbon comp resistors, etc.  But I'll bet if you get a great capsule, one of the aforementioned transformers and enough tubes of the type you choose to use to find a quiet, non microphonic one (not a trivial task), you'll be rewarded with a great tool to record music with. And isn't that what it's all about?

Naahhh...

I've read few times  that headbasket in U47 is most important
Of course none of this transformers will suck, three great manufacturers, great quality products - of course each will be somehow different.
Still my opinion is that even if ten nitpickers  will prefer something else than ami, even will share their opinions in that or other way, still i believe that hundred of other users will be really satisfied and happy. Good product will defend itself. That's why i don't understand some panic behaviors...
I would much more concern about quality of some other products which are made in china , got new sticker and "manufacturer" sells only bullshit stories about it
Anyway, devil is in details, but many people don't need these details. Many guys want to build microphone as a "tool", because it's cheaper, usual worth etc. But when you build because you like it, you build it much enough that sometimes it can be boring to make another same topology etc. then these details are starting to be really important
All depends on needs and reasons.

 

[gyraf]

(..on a side note, please remember that this is the GroupDIY, not the 'slutz - so please stay away from anything that could be interpreted as personal attacks..)

Jakob E.

 

[Avgatzeblouz]

Wow, what a string. 

To the OP, I'll bet any of the transformers mentioned - AMI, Haufe, IO Audio won't SUCK. Will they all sound a bit different? Likely. But then again, how much? We are a nitpicky bunch here (from what I've seen). Not a bad thing, the devil's in the details. But in the grand scheme of things, with tube mics the sound is most dependent on (in order) - capsule, transformer, tube. Some people are very concerned with coupling caps, metal film vs. carbon comp resistors, etc.  But I'll bet if you get a great capsule, one of the aforementioned transformers and enough tubes of the type you choose to use to find a quiet, non microphonic one (not a trivial task), you'll be rewarded with a great tool to record music with. And isn't that what it's all about?

Hi Austex, thanks a lot. I am still shoppoing for the capsule, and on this side, I just want the best. So I contacted Sennheiser Canada, and I can get a Neumann K49 for 750 CAD. A Thiersch would be around 450 CAD. I personnaly am ready to wait in order to gather more money, if this capsule is worth it. After all, I agree this is the most important part. A flea F7 is around 550 CAD. Any experience someone can share ? I've read posts from Klaus Heyne stating that the Neumann capsules, even current ones, are the best (more vibey, 3D, according to his words) and most consistent ones to this day. I know quite well the M149, housing the K49, and while being a great mic, it is very clean, and far from a U47. Could that be a risk, having a mic to clean, or will the circuitry bring that 47 flavour ?

Thanks to everyone for helping me making the right decisions before jumping in the boat. I don't think I will have the chance to do this very often, as my main job is mixing, so I wanna make it right, to enjoy every moment I use it, without any regrets.

 

[ln76d]

In my opinion, most known sound of U47 is M7 capsule, that's why i mentioned earlier Thiersh and Dan.
Also prices are pretty good. For the first build i would definately go for it, after all you can always change capsule for K49 and have M7 for another build No one said that it need to be installed forever in one mike. I often make roatation of some parts in my builds

 

[Avgatzeblouz]

In my opinion, most known sound of U47 is M7 capsule, that's why i mentioned earlier Thiersh and Dan.
Also prices are pretty good. For the first build i would definately go for it, after all you can always change capsule for K49 and have M7 for another build No one said that it need to be installed forever in one mike. I often make roatation of some parts in my builds

And I guess I can easylly resell the K49 if I don't like it.