Unbelievable. Not worthy is correct.
:thumb: :guinness: :thumb: :guinness: :thumb:
:thumb: :guinness: :thumb: :guinness: :thumb:
so, I finally finished my Telefunken Ela M251E project...
- Thread starter scott_humphrey
- Start date
Help Support GroupDIY Audio Forum:
tommypiper
Well-known member
Excellent. Inspiring! Would love to see a parts list. Maybe I'll try one some day.
scott_humphrey
Well-known member
[quote author="tommypiper"]Excellent. Inspiring! Would love to see a parts list. Maybe I'll try one some day.[/quote]
A parts list has been added to the web page. The power supply is the same as Jakob's except that three 27 kOhm resistors are used to drop the B+ voltage down to 120V. Four 47 uF electrolytic capacitors are used to filter the B+, like in the original Telefunken schematic. I wasn't planning on drawing out the power supply schematic, but I might do this at some point if people are interested.
Also, the link has been updated:
http://www.treblebooster.com/m251e/telefunken_ela_m251e_circuit.htm
A parts list has been added to the web page. The power supply is the same as Jakob's except that three 27 kOhm resistors are used to drop the B+ voltage down to 120V. Four 47 uF electrolytic capacitors are used to filter the B+, like in the original Telefunken schematic. I wasn't planning on drawing out the power supply schematic, but I might do this at some point if people are interested.
Also, the link has been updated:
http://www.treblebooster.com/m251e/telefunken_ela_m251e_circuit.htm
fuzzbox
Well-known member
:shock: wow that is just amazing. Nice work, must feel great singing into a mic you built yourself. How much did Tab ask for the tranny?
Also how many tubes did you have to try before finding a quiet one?
I'm in :shock:
Also how many tubes did you have to try before finding a quiet one?
I'm in :shock:
I also had an invitation to some xxx-site... never mind, will scan my puter with some spywarekillers later today. :razz:
Do you have an estimation of the costs to built this?
Also, what do you use as spider, was that diy too?
Cheers,
Tony
Do you have an estimation of the costs to built this?
Also, what do you use as spider, was that diy too?
Cheers,
Tony
G
Guest
Guest
Yea, I am curious about the shockmount too, the whole package looks sweet!
scott_humphrey
Well-known member
[quote author="JCMaudio"]Yea, I am curious about the shockmount too, the whole package looks sweet![/quote]
I bought the shockmount from Peluso as well as the capsule. I'm not sure about the total cost of the mic because I collected the parts for this over the last year and a half or so.
-Scott
I bought the shockmount from Peluso as well as the capsule. I'm not sure about the total cost of the mic because I collected the parts for this over the last year and a half or so.
-Scott
scott_humphrey
Well-known member
[quote author="tony dB"]I also had an invitation to some xxx-site... never mind, will scan my puter with some spywarekillers later today. :razz:
Cheers,
Tony[/quote]
Sorry about that. I've contacted my web hosting service. Hopefully the problem will be taken care of soon.
Cheers,
Tony[/quote]
Sorry about that. I've contacted my web hosting service. Hopefully the problem will be taken care of soon.
scott_humphrey
Well-known member
[quote author="tony dB"]any rough estimation on costs? :wink:
If you prefer not to say, just tell me and i will shut up about it...
Tony[/quote]
I honestly don't know. I had some of the parts around already.
If you prefer not to say, just tell me and i will shut up about it...
Tony[/quote]
I honestly don't know. I had some of the parts around already.
scott_humphrey
Well-known member
[quote author="maxwall"]Scott,
a fine job....... Did you use the T14 type transformer from TabFunkenwork
He makes two types the standard T14/1 and just a plain T14. The plain T14 is said to have a better low end frequency response ?[/quote]
Thanks.
I used what Oliver called a T314. It is a larger transformer than the T14/1, which is very small. I believe that he said it would be optimized for the ela m251e circuit.
I haven't compared the two types of transformers side by side. The larger transformer should be able to handle more bass before saturation. Sometimes, though, transformers sound nice when they are pushed a bit , and this can increase the perceived bass response, so the smaller transformer may have the sound that you're after. Maybe someone who knows more about this could comment.
-Scott
a fine job....... Did you use the T14 type transformer from TabFunkenwork
He makes two types the standard T14/1 and just a plain T14. The plain T14 is said to have a better low end frequency response ?[/quote]
Thanks.
I used what Oliver called a T314. It is a larger transformer than the T14/1, which is very small. I believe that he said it would be optimized for the ela m251e circuit.
I haven't compared the two types of transformers side by side. The larger transformer should be able to handle more bass before saturation. Sometimes, though, transformers sound nice when they are pushed a bit , and this can increase the perceived bass response, so the smaller transformer may have the sound that you're after. Maybe someone who knows more about this could comment.
-Scott
Oliver Archut
Member
Hello everybody,
Scott send me an e-mail asking if I could give some basic info on the T14 family of x-formers.
The T14 originated from the NWDR/IRT R&D lab and was build for several years by Albert Hiller KG in Hamburg. A high ratio mic output build around the german DU/LL lamination type. Original designed for the Hiller MSC type of tubes, but also works well with 12AT7, 12AY7, AC701, etc.
AKG utilized the Hiller T14 in their C12 mic, but after Hiller went into liquidation, they used for a while the Henry Radio M core x-former, and in early 1960 they changed to the T14/1 made by Haufe and Telefunken Hanover. Telefunken specified this x-former for the build in low end roll off (starting at 80Hz 6dB an octave) to comply with the ratio specs demand for 40 Hz cut. AKG than also implemented it in the C12 and 24 as well as some other mic.
We here at TAB-Funkenwerk started to build new version of most classic condenser output x-former, like T14 and T14/1 but also venturing into some modern approach designs to archive more low end, better high end response as well as sonic resolution.
The BV314 has the same ratio than the earlier T14 type designs, and aside the higher bandwidth nearly three times as much headroom than the historic ones.
Hope that answers some of your questions.
Best regards,
Oliver
Scott send me an e-mail asking if I could give some basic info on the T14 family of x-formers.
The T14 originated from the NWDR/IRT R&D lab and was build for several years by Albert Hiller KG in Hamburg. A high ratio mic output build around the german DU/LL lamination type. Original designed for the Hiller MSC type of tubes, but also works well with 12AT7, 12AY7, AC701, etc.
AKG utilized the Hiller T14 in their C12 mic, but after Hiller went into liquidation, they used for a while the Henry Radio M core x-former, and in early 1960 they changed to the T14/1 made by Haufe and Telefunken Hanover. Telefunken specified this x-former for the build in low end roll off (starting at 80Hz 6dB an octave) to comply with the ratio specs demand for 40 Hz cut. AKG than also implemented it in the C12 and 24 as well as some other mic.
We here at TAB-Funkenwerk started to build new version of most classic condenser output x-former, like T14 and T14/1 but also venturing into some modern approach designs to archive more low end, better high end response as well as sonic resolution.
The BV314 has the same ratio than the earlier T14 type designs, and aside the higher bandwidth nearly three times as much headroom than the historic ones.
Hope that answers some of your questions.
Best regards,
Oliver
By the way, the t14/1 is a fairly unimpressive transformer, especially in later vintages, as I'm sure Oliver will verify.
Sorry to correct for a typo, but the word "ratio" in Oliver's third paragraph, the one beginning in "AKG utilized..." should actually be "radio". Most of the gear we all lust for was critically designed in the early days by some mighty high flyers in both acedemia (when it meant something) and broadcasting.
The guys in the 30's, 40's, and 50's really knew what they were doing.
By the 60's and 70's, things started slipping, or maybe in reality, commerce caught up with them, and true engineering, from first principles fell by the wayside.
So a transformer with inferior iron, that intrinsically did a part of the low frequency filtering required by the broadcasters was used instead of a wider bandwidth part, with appropriate filtering. The difference? While the transformer will limit the low end, it does that and adds distortion caused by core saturation, as well as amplifier distortion artifacts caused by the lower inductance of the smaller transformer, but filtering with a capacitive circuit will add virtually no distortion to the active circuit, and in fact protect the transformer from large low frequency signals. To a degree...
All engineering decisions are tradeoffs of course, but I think this is a good example of the beginning of the slide.
Just think about it, what has AKG done lately that's really good?
The later C24's are certainly pale imitations of their former glory.
Sorry to correct for a typo, but the word "ratio" in Oliver's third paragraph, the one beginning in "AKG utilized..." should actually be "radio". Most of the gear we all lust for was critically designed in the early days by some mighty high flyers in both acedemia (when it meant something) and broadcasting.
The guys in the 30's, 40's, and 50's really knew what they were doing.
By the 60's and 70's, things started slipping, or maybe in reality, commerce caught up with them, and true engineering, from first principles fell by the wayside.
So a transformer with inferior iron, that intrinsically did a part of the low frequency filtering required by the broadcasters was used instead of a wider bandwidth part, with appropriate filtering. The difference? While the transformer will limit the low end, it does that and adds distortion caused by core saturation, as well as amplifier distortion artifacts caused by the lower inductance of the smaller transformer, but filtering with a capacitive circuit will add virtually no distortion to the active circuit, and in fact protect the transformer from large low frequency signals. To a degree...
All engineering decisions are tradeoffs of course, but I think this is a good example of the beginning of the slide.
Just think about it, what has AKG done lately that's really good?
The later C24's are certainly pale imitations of their former glory.
scott_humphrey
Well-known member
[quote author="Brian"]That looks awesome, Scott! Congratulations.
I couldn't find the tube info on your parts list, what did you use?[/quote]
Thanks, Brian. I used a NOS 6072A.
I couldn't find the tube info on your parts list, what did you use?[/quote]
Thanks, Brian. I used a NOS 6072A.
