C1 capacitor in U47

[Moby]

I think the problem lies in the fact that both capcitors sound great. Is there a difference? It is hard to tell with the variances that could have occured during performances.

I agree about that both caps sounds great but that proves the fact that upgrading U47 is not needed. But there is a slight difference what genuine U47 makes "more modern" . I chimed first time because of that. What's better? Well, it's just a matter of taste. But again, I choose original one because it sounds like U47 sounds .  Misha, thanks for your efforts and time to experiment . Cheers

 

[o3misha]

You know what guys? And really, I will upload another couple of files. Then you will have two examples for each capacitor's influence. This will allow a more detailed understanding of the difference in the sound of capacitors and eliminate so random factor. By the way, I did not promise a huge difference, is not it? But pay attention to the dynamics and coloration treble and presence.
Of course, original caps are great, but....
http://files.mail.ru/15CCF48717E646A1BF28F07FE44082A1

 

[MagnetoSound]

The shame? Admittedly? I don't understand it. Do you mean that all guys here have the same opinion with you ? This is the bold statement.....(Q.Tarantino) How would you try to choose the right color of the sound, if not to listen to some examples?

I find no shame in this test. I personally heard the difference in the sound of capacitors.

No, I meant no offense. When I said it was a shame, I simply meant I thought it was a pity that, in my opinion, the test was flawed. You asked for opinions, and I responded in truth.

Naturally, I respect your right to do whatever testing you choose and to submit the data to the forum for comment if you wish. But it works both ways. If you solicit a response to your submissions then you, in turn, must respect my right to give an honest answer. I am not going to express an opinion on the comparison if I don't feel that I can trust the validity of the test absolutely.

Of course, I could be wrong. It's only my opinion. 

 

[dmp]

I listened to the samples - thanks for posting.
I thought samples A and D sounded better that samples B and C. There was something about B and C that struck me as a little wonky in the tone.
Honestly I expected I would not be able to tell the difference. I lot of mic tests are more subtle than these, I felt.
But maybe I'll listen tomorrow and think something completely different.

 

[Balijon]

I listened to all your 4 samples....
I would worry less about your selection of 'C's' and suggest you pay more attention to correct your mic placement.... 8)

 

[dmp]

Looking at the schematic I have a lot of trouble understanding how C1 is going to affect the mic output.
It seems like it was probably intended to increase rejection of noise from the power supply.
And if it does affect the audio, I would not think it would be for high frequencies. The C1 and 30k resistor can be thought of as a filter, where the voltage at the C1 node is stabilized at high frequencies. The 3dB point of C1 and 30k would be 5 Hz?

 

[MagnetoSound]

And if it does affect the audio, I would not think it would be for high frequencies.

C1 is the backplate grounding cap, 10nF. Yes, it forms a LPF with the polarising resistor R1, which is 100M. Corner freq is 0.2Hz. Who cares what the -3dB point is?  ;D

It is, however, directly in the audio path. Dielectric will affect audio quality.

 

[dmp]

Whoops, I thought you guys were talking about the cap on the plate supply.

 

[VictorQ]

Still it is in series with the capsule, which is at least 100 times higher impedance... So not a lot of signal voltage is dropped across C1, and thus it shouldn't affect sound quality very much..

 

[MagnetoSound]

Still it is in series with the capsule, which is at least 100 times higher impedance... So not a lot of signal voltage is dropped across C1, and thus it shouldn't affect sound quality very much..

Right. The difference will be subtle, dominated by other components - primarily, of course, the capsule itself.

Not to mention placement. 8)

 

[moamps]

O3misha raises some good questions about the parts quality in the U47, IMO.
C1 should be very low microphonic, very low leakage capacitor, what an old ceramics aren't.
And, if one mic worth USD10k, I don't see any problem with expensive parts inside.
Just the opposite,  I expect that.  Maybe not D*****d, but some decent PP or PTFE for sure.

Regards,
Milan

 

[Moby]

C1 should be very low microphonic, very low leakage capacitor, what an old ceramics aren't.

As far I know in this (samples) U47 C1 is polystirene . So all we hear is polystirene against Duelund. BTW, to be honest in the repeated audio test samples I can't hear a huge difference. Both is usable.

 

[o3misha]

C1 should be very low microphonic, very low leakage capacitor, what an old ceramics aren't.
And, if one mic worth USD10k, I don't see any problem with expensive parts inside.

C1 is the backplate grounding cap, 10nF. Yes, it forms a LPF with the polarising resistor R1, which is 100M. Corner freq is 0.2Hz. Who cares what the -3dB point is?  

It is, however, directly in the audio path. Dielectric will affect audio quality.

precisely, guys!The difference is small. But it is, it is exactly. I hear a slight compression on High frequencies, which I really like in sound with  paper capacitor. I want to explain why using  D#####d, not other paper capacitors. It's not as bulky as other modern PIO caps. Modern technology allows to avoid leakage, which has always been characteristic of the most of old PIO caps. Also D#####d very reliable and stable when operating at high temperatures. It has very little distortion factor. It would be interesting to try it as C3, but 1uf is too bulky even for long body. 

p.s Many famous modern companies ignore the small differences that make capacitors. Capacitors always affect the sound. Therefore, modern microphones (u47 clones) often sound brighter. Most people  like it, but not all.

 

[Moby]

Therefore, modern microphones (u47 clones) often sound brighter. Most people  like it, but not all.

Me no like it

 

[o3misha]

I also don't like it. Thats why I prefer PIO or PIW caps.

 

[Melodeath00]

What would be a way to get the most "authentic" capacitors for a U47 clone? Especially so it is not brighter like a modern clone (which I suspect also has to do with tubes)

 

[o3misha]

a,с - paper cap, b,d - polyester cap . 8)

 

[Rossi]

Really? I was certain B and C was the same cap (the softer sounding one), whereas A and D sounded a bit brighter in comparison.

 

[o3misha]

As some have questioned the microphone position and articulation, I decided to select the most similar to the articulation of the files. Thus, C and D are more similar. Take the headphones. Choose any of equalizers and steer files. The difference is more noticeable. I hear the more subtle differences as to hold these records, and I know that it is to be understood as the difference.

 

[Rossi]

Seriously, if B and C sound more similar (at least to me) despite the different caps, that should tell us something. I think we can assume that you tried your best to record with identical parameters. Still, the unavoidable little differences in playing and placement overshadow whatever difference the two C1 caps produce. In fact, I think most acoustic guitars vary more from day to day because of changing weather and humidity.

Not saying that you should use any old cap, even in this position, but I think we can go on using non-esoteric high quality film caps without remorse.