Where to start for an exact accurate version of C800G

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I can't bother (sorry) to go through all the documentation i've gathered on it
I tried very hard to find any available information on the c-800g, but nowhere did I see what you wrote about the transformer of this microphone ..

Do you have access to Sony insider information on this microphone?
 
Last edited:
I can't bother (sorry) to go through all the documentation i've gathered on it, although i'm right now in the process of cloning a c800.

https://groupdiy.com/threads/sony-c800-inspired-body.81262/
It has been reported during the years the c800 is designed for best possible technical performance, hence the cooling device as well. It is obvious just by looking at the size of it the imperative was transparency, bandwidth... that thing is squeaky clean. Rather high anode voltage - headroom, transformer has to be able to cope with the levels.

This is a nice summary on c800.

http://www.foxaudioresearch.ca/c800clone.htm
Maybe @Moby has more details on the specs.
Hey, I repaired this microphone once but I did not measure the transformer. Maybe I can ask the owner to give me the "specimen" so I can analyse the Iron in details.
 
I wonder: Would the designers of the C800G have achieved their goals just as well with solid-state; other than the tube perigee? If not, considering the date of design, what about today; as things have changed a lot in 30-years?
 
Last edited:
I wonder: Would the designers of the C800G have achieved their goals just as well with solid-state; other than the tube perigee? If not, considering the date of design, what about today; as things have changed a lot in 30-years?
Exactly, it seems for what they were trying to achieve the solid state might have been a "better" option.
 
On the topic of building a C800G inspired mic (maybe solid state though), which capsule would be best if not using the original? Something like Takstar's CTS-2, one of the brighter Chinese K67s (maybe whatever is in the Sterling mics), or 797s brighter K67?
I bet there would be a market for that transformer replica.
Are there any easily available transformers that would work similarly enough?
 
Find a copper ring K67 antiques capsules, is said to be in the '60 s exact copy version of the German aid, as the decades passed, the tone is very good, ready to copy my C800G.

1.jpg2.jpg3.jpg4.jpg5.jpg
 
Last edited:
On the topic of building a C800G inspired mic (maybe solid state though), which capsule would be best if not using the original? Something like Takstar's CTS-2, one of the brighter Chinese K67s (maybe whatever is in the Sterling mics), or 797s brighter K67?
Are there any easily available transformers that would work similarly enough?
I'm still trying to find one that is close. There is a misconception the c800 capsule is a very good clone of Neumanns k67. This is not true, they seem to be very different. As far as the transformer goes, just go for the most transparent one. I would go with Lundahl or Cinemag.
 

Attachments

  • Screenshot_20220830-102436_Google.jpg
    Screenshot_20220830-102436_Google.jpg
    371.9 KB · Views: 2
This is what happened when converting Japanese text.

The output transformer is made in America. Mahi's microphone design begins with determining the size of the microphone capsule. As shown in the figure, the maximum diameter of the diaphragm is 1 inch to 1.5 inch, which determines the diameter of the body to put the capsule in. The style of microphone design is to select a core material that is large enough to fit inside the transformer. The turns ratio of the transformer is '7.1' for C-SOoG and 2_5:1 for C-BOO.Incidentally, C-37A is 4.1. The tubes are his 6AUGA, used in a triode connection - the working circuit is the C-SOOG is a grounded cathode circuit with his gain of 17dB and the G-800 inherits the C-37A. KaHis sword, Folo type 7 circuit is used. The turns ratio of the transformer is determined by this. Transformer design: From the requirements of microphones in the digital age, the direction is to increase the maximum input sound pressure while increasing the sensitivity of the microphone, and the smaller the turns ratio, the better. Adjustments are made with priority given to sound quality under the condition that characteristics are easy to produce.
Wires used in transformers are usually obtained in the United States. Rather than pureness, the one that met the total conditions from the manufacturing process to the usage of the wire was selected4.
 
Hey, I repaired this microphone once but I did not measure the transformer. Maybe I can ask the owner to give me the "specimen" so I can analyse the Iron in details.
- It would be great !!!
Maybe you could measure the inductance and DCR of the windings of this transformer ?... :)
 
JJ Akita uses the same transformer as c800g allegedly made by the same company that made them for Sony. Again, high headroom claim points to a transparent performance.

Hmmm...their description of their buffer circuit:
"The 6AU6 tube has a naturally compressed, clean and transparent sound"

Transparent - clear, not visible, making no impression
compressed - reduced from original dynamic range

So is it transparent, or can it not handle the full dynamic range and causes amplitude distortion? It's like politicians speaking, say opposite things and hope that everyone listening hears only what they want to hear and doesn't realize they just contradicted themselves in a single sentence.
 
Well, that description is pretty much bs. I'm just pointing to various sources i've found that lead me to believe the transformer is meant to be as clean as possible. There are other sources as well. I'm having a tough time keeping track of every resource i've collected during the years on so many components of various mics. When it comes to c800g transformer i made just a comment on my checklist - should be as transparent as possible. Never found anything that led me to believe it should be anything else.

The whole point of the design seems to be improvement on older designs, and they just went over the top in every aspect brute force style. Plate voltage, reduced body resonances, noise and THD (peltier element)... Just by the look of it, the transformer follows the trend. It wouldn't make any sense whatsoever to do all of the "improvements" on traditional design, and then make a oversized permalloy transformer that colors the sound in any significant way.

The only reason they went for a tube design seems to be the subjective preference, and sympathy for "tube sound" which they never managed to quantify/measure. Roughly paraphrasing the documents in Japanese.
 
Last edited:
Hmmm...their description of their buffer circuit:
"The 6AU6 tube has a naturally compressed, clean and transparent sound"

Transparent - clear, not visible, making no impression
compressed - reduced from original dynamic range

So is it transparent, or can it not handle the full dynamic range and causes amplitude distortion? It's like politicians speaking, say opposite things and hope that everyone listening hears only what they want to hear and doesn't realize they just contradicted themselves in a single sentence.
Exactly. Audiophools marketing. I will do my best to measure and publish the details of the original transformer
 
Back
Top