AKG Perception P220 to Neumann u87 5 min mod ( p200, p100, p400, p420? )

[micolas]

Do you know guys a "similarly good" - not harsh, smooth - sounding alernative with less self noise? Rode NT1 with capsule swap or even a DIY mic?

https://groupdiy.com/threads/a-good-mic-pls.90113/post-1191652
*

In order not to pollute this thread and to make it easier to search for information, in the case of another topic, you must open a new thread with a title that reflects exactly what it is about.

 

[Masiusima13]

Just got my new P420 modded, replaced the stock cap with a 680pf smd 50v NP0 cap. Sounds glorious! Compared it to a Rode K2 with a telefunken tube that costs 3-4x the price of this mic and the akg fared well in the shootout, doesnt sound cheap at all.

One question for all you that have a newer P420, i noticed the capsule slightly leaning towards the back of the mic in the headbasket, is it anything to worry about? Its nothing too dramatic but it's messing with my ocd. Is this normal, can anyone compare with their newer p420?
Heres some pics attached

 

[k brown]

Just got my new P420 modded, replaced the stock cap with a 680pf smd 50v NP0 cap. Sounds glorious! Compared it to a Rode K2 with a telefunken tube that costs 3-4x the price of this mic and the akg fared well in the shootout, doesnt sound cheap at all.

One question for all you that have a newer P420, i noticed the capsule slightly leaning towards the back of the mic in the headbasket, is it anything to worry about? Its nothing too dramatic but it's messing with my ocd. Is this normal, can anyone compare with their newer p420?
Heres some pics attached

As long as the capsule is securely attached to the yoke, and the yoke to the head base, no issue at all; in fact it's micro-preferrable - the diaphragm is a bit less parallel to the grille, which is all to the good.

 

[micolas]

Just got my new P420 modded, replaced the stock cap with a 680pf smd 50v NP0 cap. Sounds glorious! Compared it to a Rode K2 with a telefunken tube that costs 3-4x the price of this mic and the akg fared well in the shootout, doesnt sound cheap at all.

One question for all you that have a newer P420, i noticed the capsule slightly leaning towards the back of the mic in the headbasket, is it anything to worry about? Its nothing too dramatic but it's messing with my ocd. Is this normal, can anyone compare with their newer p420?
Heres some pics attached

As long as the capsule is securely attached to the yoke, and the yoke to the head base, no issue at all; in fact it's micro-preferrable - the diaphragm is a bit less parallel to the grille, which is all to the good.

@Masiusima13

I looked at the 2 black P420s. The capsule is vertical. Through the mesh you can see the protective hat on top. It's an optical illusion.
If OCD doesn't let you sleep peacefully, open the headbasket and check if the capsule's mounting screws in the saddle are tight.

 

[Masiusima13]

The capsule seems attached tightly, no rattling or any moving, it just seems like the post is angled towards the back a bit.

 

[micolas]

The capsule seems attached tightly, no rattling or any moving, it just seems like the post is angled towards the back a bit.

Sometimes the capsule is not perfectly seated in the saddle.
Loosen the screws, fix the capsule perfectly vertical and tighten the screws again while keeping the capsule in the correct position.
I have done this many times with all kinds of capsules.
And often the hat is carelessly fastened
(Made in China)

 

[micolas]

If the rod is tilted , then place a thin plastic tape, foil, etc. (one layer or more), under the capsule, under the half that is tilted down.
*****
Some Rode microphones have capsules tilted a few degrees, but the Perception does not.

 

[Masiusima13]

Thanks for the help! The rod is definitely at a very slight angle along with the saddle of the capsule thats attached to the rod. Im not that bothered by it as long as the few degrees of tilt wont affect the sound at all so ill just leave it alone instead of messing and potentially damaging something

 

[micolas]

Thanks for the help! The rod is definitely at a very slight angle along with the saddle of the capsule thats attached to the rod. Im not that bothered by it as long as the few degrees of tilt wont affect the sound at all so ill just leave it alone instead of messing and potentially damaging something

Ok. You will have a slight imbalance between Front and Rear in Omni or Figure8.

 

[k brown]

Ok. You will have a slight imbalance between Front and Rear in Omni or Figure8.

I seriously doubt this would be audible.

 

[Masiusima13]

Ill be using it in cardioid 99% of the time so its not a problem, ive tested figure of 8 though and both sides sound normal, with smaller sonic differences as its usually expected from two sided capsules

 

[micolas]

Ill be using it in cardioid 99% of the time so its not a problem, ive tested figure of 8 though and both sides sound normal, with smaller sonic differences as its usually expected from two sided capsules

I seriously doubt this would be audible.

It makes no sense to feed the OCD.
The differences are within the allowed tolerances.
Even Neumann admits +/-2%.

 

[Екатерина]

Friends, can the old versions of MXL 2001 and MXL V67 also be modified in this way?

 

[Екатерина]

Of course, I am also puzzled about the attenuation changes caused by FET changes. If someone could simulate the impact of 2SK170 on the frequency response curve, it would be even more perfect

 

[micolas]

Friends, can the old versions of MXL 2001 and MXL V67 also be modified in this way?View attachment 147616

Of course, I am also puzzled about the attenuation changes caused by FET changes. If someone could simulate the impact of 2SK170 on the frequency response curve, it would be even more perfect

The subject has been studied extensively.
But without the existing capsule in Perception the results will be different.

https://groupdiy.com/threads/akg-pe...in-mod-p200-p100-p400-p420.67473/post-1019616

 

[Екатерина]

The subject has been studied extensively.
But without the existing capsule in Perception the results will be different.

https://groupdiy.com/threads/akg-pe...in-mod-p200-p100-p400-p420.67473/post-1019616

I read the simulation and it also explained the impact of 2N3819 on the frequency response curve. Can we get good results by replacing the K67 capsule and changing the fet to 2N3819? Perhaps we need to readjust R7 for bias

 

[Khron]

changing the fet to 2N3819?

Why?

Perhaps we need to readjust R7 for bias

There's a reason the source resistor in the U87 is a trimmer (even two 3819's can be way off in parameters between them).

 

[Екатерина]

Why?



There's a reason the source resistor in the U87 is a trimmer (even two 3819's can be way off in parameters between them).

In the previous post, James-F created a simulation circuit and showed different attenuation amplitudes for 2n3819 and LSK170B. Therefore, in order to make the attenuation of V67 effective, does it need to be changed to 2n3819? Maybe I misunderstood something

 

[micolas]

In the previous post, James-F created a simulation circuit and showed different attenuation amplitudes for 2n3819 and LSK170B. Therefore, in order to make the attenuation of V67 effective, does it need to be changed to 2n3819? Maybe I misunderstood something

Keeping the stock jFET and the current BIAS (which is more permissive), only by increasing the NFB capacitor, (i.e. proceeding as in Perception) the result is good. I repeat, the capsule does not behave like Takstar or 797.
Of course, some of us have repolarized the jFET, or changed the jFET. (Personally I liked 2sk30)
Or we have rebuilt a cardioid U87 inside.

 

[micolas]

@Екатерина

There are a lot of microphones that share this scheme, so the topic is debated in many threads in the group. Everyone makes their own decisions.
But, it is advisable to analyze other microphones in dedicated threads, this one addresses the Perception series.