Heiserman 87 & Maiku 87

I just did a frequency sweep on these two different capsules.

Interestingly the Maiku has less top end which is what I heard with my ears comparing to the HK 87 and an original Neumann 87.

Wondering if this could potentially be down to the polystyrene cap at C6 being faulty or whether others had noticed a similar flatter response with the Maiku?

Going to try another 220pf and also a 170pf at C6 to see if that makes any difference.

My HK 87 build has a 270pf at C6 and 0.1uf at C5.

Graph attached below.

HK87 in Green
Maiku in Blue

Yes, Maiku K87 is more flat than most K67/k87 capsules. It is intentional and made due to modified backplate pattern. 
Most accurate response vs. Neumann K67 i had with 150pF, Neumann 220pF.
I truly like Maiku capsules, but i'm not typical clone builder
HK87 is brighter than original K87, stam if i remember correctly is using 300pF for it.
Look on the backplate pattern

Great thanks ln76d, thats great too know!

I should also clarify that wasn't suggesting that there was something wrong with the Maiku, as it sounds great,  just noticed it was less bright. Also I had some problems with jfets with this build so was wondering if I had knackered the polystyrene cap with too much cleaning.

Will compare the backplate patterns  ; There is a nice low end on the Maiku.

Cheers,

Piers

I can confirm what Piotr said. I compared Maiku K87 and original Neumann K87 in the same U87 circuit and 150pF was my final value for C6. Maybe you could try Maiku without C6 capacitor.

Thanks for the measurements. I wish there were more of them.

Would you mind sharing the plots without smoothing? There is a 'fault' in most k67 copies not visible when FR is smoothed. I am just curious if these exibit some random dipps typical for cloned capsules.

Vac11 said:

I can confirm what Piotr said. I compared Maiku K87 and original Neumann K87 in the same U87 circuit and 150pF was my final value for C6. Maybe you could try Maiku without C6 capacitor.

Click to expand...

Cheers, might try a very low value to see the effect on the top end. Will post the results.

kingkorg said:

Thanks for the measurements. I wish there were more of them.

Would you mind sharing the plots without smoothing? There is a 'fault' in most k67 copies not visible when FR is smoothed. I am just curious if these exibit some random dipps typical for cloned capsules.

Click to expand...

Of course will do. I should say that my setup is far from scientific, I only use it to compare the different builds against each other.

One is of the HK 87 and Neumann 87 (not ai) The other is the HK87 capsule and Maiku 87 capsule.

The dip at 750hz is most probably the crossover between the speaker drivers. It appears in all mics.

Couldn't attach two files. So here is the HK & Maiku

Are you able to make measurement also with measurement microphone and subtract the speaker response from the main measurement?

ln76d said:

Are you able to make measurement also with measurement microphone and subtract the speaker response from the main measurement?

Click to expand...

Hi Piotr,

I don't have one available to me here unfortunately which isn't ideal I know. I will hopefully get hold of one in the very near future. I was looking at a couple recently.

I'd love to figure out how to do that in REW (Room EQ Wizard), for my own measurements 

ln76d said:

Are you able to make measurement also with measurement microphone and subtract the speaker response from the main measurement?

Click to expand...

Here is the HK capsule and the Maiku this time with  C6 (10pf).

HK Build - C6 - 270pf C5 - 0.1uf
Maiku - C6 - 10pf C5 - 0.033uf

I'll also post without smoothing.

Khron said:

I'd love to figure out how to do that in REW (Room EQ Wizard), for my own measurements 

Click to expand...

I don't know is it rew or not and what options it have, i don't use it, that's why i'm asking.
So figure it out.

PG_Sax said:

Here is the HK capsule and the Maiku this time with  C6 (10pf).

HK Build - C6 - 270pf C5 - 0.1uf
Maiku - C6 - 10pf C5 - 0.033uf

I'll also post without smoothing.

Click to expand...

wow, so it not only looks like hk is bright like most chinese capsules (or even brighter) but also have weaker low end response since you used 100nF to get similar low end for standard 33nF.
Try Maiku with 150pf  - 10pF only give you signal attenuation but far from audible range.

ln76d said:

I don't know is it rew or not and what options it have, i don't use it, that's why i'm asking.
So figure it out.

wow, so it not only looks like hk is bright like most chinese capsules (or even brighter) but also have weaker low end response since you used 100nF to get similar low end for standard 33nF.
Try Maiku with 150pf  - 10pF only give you signal attenuation but far from audible range.

Click to expand...

Have some different value capacitors on order so definitely going to try that out.

In regards to C5 I didn't see a whole lot of change at 80hz when changing 0.1 possibly 0.5-1db but difficult to say due to my weak test setup. Below 80hz there was a small increase but not much.

I have some charts for the HK87(220pf) and U87 if there is any interest?

PG_Sax said:

Have some different value capacitors on order so definitely going to try that out.

In regards to C5 I didn't see a whole lot of change at 80hz when changing 0.1 possibly 0.5-1db but difficult to say due to my weak test setup. Below 80hz there was a small increase but not much.

I have some charts for the HK87(220pf) and U87 if there is any interest?

Click to expand...

Yes i'm definately interested Try with 330nF-470nF for both capsules

Thanks a million. As far as i can see none of these capsules exhibit those dips i've seen in cheaper k67s. They are often present before high end peak.

However i am surprised that the praised Heiserman is so bright.   

Khron said:

I'd love to figure out how to do that in REW (Room EQ Wizard), for my own measurements 

Click to expand...

I do it by setting up a measurement mic at the same spot where i measure my mics and measure response of it. Then i export that response of my measurement mic as calibration file. Then i use that calibration file with measurements of my mics. It flattens out the response a lot.

There is one downside though, measurement mics are omni, and i am mostly interested in cardioid response of my mics. Omnis don't have proximity effect, and are somewhat more affected by room acoustics.

For critical measurements of my ''clones'' i don't use reference mic (calibration), i do it just like PG Sax did, reference mic just adds one more variable. 

Here is the effect of the 330pf that I had done on the HK87 before.

In these charts the mics were measured slightly differently and I can't be sure of the level matching. But you can see the rough effect of the different capacitors at C5 & C6. These are all with the HK87 capsule.

First is C5 - 470nf / 0.47uf C6 - 330pf

HK87 - 220pf / 0.033uf

ln76d said:

Yes i'm definately interested Try with 330nF-470nF for both capsules

Click to expand...

Potentially I will do this, might have to have a break for the time being

The frequency sweeps are good as a reference but I definitely think ears are probably a better judge with the setup I have at the moment.

What I don't really understand is I'm sure I level matched the HK87 and Maiku 87, but the Maiku shows more low end on the graph?

It seems both these capsules can be very close to the original.

Thanks for the comparisons! 

Banzai said:

Thanks for the comparisons! 

Click to expand...

No problem 

I have just received some more capacitors so will put a graph up with all there mics together when I get some time next week.

I have used both (HK87 & Maiku 87) on soprano & alto saxophone and they both sound excellent!