AKG 535 sounding thin

Hi guys. Does anyone have experience with AKG 535? I just bought one used, mint condition as i heard a lot about this mic beating hi end mics in blind shootouts etc.

However mine lacks bottom end. It's almost as HPF is on, whilst it isn't.

I compared it to KSM44 and my modded Røde NT3, they both kill it.

Hi end is great, not hyped, much like KSM44.

I did shootout at about 30 cm distance. The only time it sounds fatter is when im totally into it. Proximity does it's thing.

I wonder if it's designed this way as a handheld, or is there something wrong with mine. Anyways this thing as it is can't beat any mic, let alone hi end stuff.

Virtually all (directional) stage microphones have bass roll off to compensate for close proximity.
The 535 has some EQ on the body though and in the proper position should not sound thinner than others.
Sooner the opposite.

AKG, by Harman, by Samsung has recently discontinued this mic, unfortunately.
It's a back electret condenser that's maybe not the most noiseless, but it's a classic for a reason.
Sinatra had a gold plated one FWIW.

Jim Williams used to do an electronics mod on these.

Our own Marik does the same to the AKG C1000s, which brings a stunning improvement IMO. I've always wondered what he could do with the 535.
Let's hope he chimes in.

I'll mod it with pleasure

Stephen Webber said in an inteview it always comes first or second in blind vocal shootouts no matter how many mics you put against it, an now i'm puzzled. In studio, on vocals at some distance i wouldn't even consider it. However it does have nice top end.

Now that i have mentioned Røde NT3 i strongly suggest modding this mic, and trying it out. There is video i made. It is unbelievable.

Pics

#2

I have measured frequency response of the circuit, and it has slight LF drop starting at 200hz and ending at -4db @50hz. HPF not engaged.

Frequency response chart kinda confirms this. The question would be how to remove that rolloff.

And schematics

The 535 hasn't been discontinued, it went out of production temporarily because it contained a substance now outlawed by EU law, it'll be back out very soon.

I don't think it's totally fair to write off AKG and blame Harman for it. Whilst it's true that they have followed the same rules everyone else has and shipped production off to china for many mics, there are some great new products - the D12VR is absolutely awsome - it's totally NOT a D12 in anyway - but as it's own thing in passive mode it completely rocks.

The thing with AKG - and I must say most of the management have remain the same for many years - is they absolutely hate the idea of what they consider obsolete technology. I spent an evening trying to convince them to do their own C12 - I showed them Telefunkens effort and Wunder. Not interested, old technology.

They told me old technology is not in company ethic and never has been.

Not really had time for this, but i couldn't resist

Main mod is change 100nF to 220nF, film cap of course.
If you have option to fit film cap, then try 1uF at the output - should works well with 220nF from the main mod.
WIma mks should be pretty small and fit.
Another thing is capsule connection, to be honest i don't remember, last time i had this mike in my hands ca. 8 years ago.
If it's connected as in the schematic then one side is polarised with 10V. Move that side to ground (if it's possible) and check is there any improvement

And please! Don't even think about making any "transformerless" mod ala Williams - i tested C460 with his mods - pretty lifeless shit!

Thanks, you are amazing as always

I'll try it out. I just have to check this schematic, as it doesn't look like the thing that's actually inside.

Our own Marik does the same to the AKG C1000s

Click to expand...

But his own mod of course; not a Jim Williams mod. 

And yes, we have Piotr, too. 

And a couple more.  .......

Come to think of it, this is some place to be. 

Timjag said:

The 535 hasn't been discontinued, it went out of production temporarily because it contained a substance now outlawed by EU law, it'll be back out very soon.

I don't think it's totally fair to write off AKG and blame Harman for it. Whilst it's true that they have followed the same rules everyone else has and shipped production off to china for many mics, there are some great new products - the D12VR is absolutely awsome - it's totally NOT a D12 in anyway - but as it's own thing in passive mode it completely rocks.

The thing with AKG - and I must say most of the management have remain the same for many years - is they absolutely hate the idea of what they consider obsolete technology. I spent an evening trying to convince them to do their own C12 - I showed them Telefunkens effort and Wunder. Not interested, old technology.

They told me old technology is not in company ethic and never has been.

Click to expand...

In June 2017 AKG ceased to exist. Vienna offices, development, manufacturing were closed.

Its now just a brand. No more dedicated development staff, no more dedicated service staff, just another brand that is handled in the new hungarian Harman factory.

Sorry guys, the schematics i downloaded from AKG site doesn't seem to be the same thing i have. This is old one, and by old specs it didn't have this LF drop either. I'll take better pics tomorrow. Not same values. I am confused additionally by SMD codes.  This is pic of old one.

I am open for suggestions, and yes this is best forum ever. Period!

I didn't found any other schematic for it - try contact AKG "china", maybe they will send you schematic. There should be PCB code - send it to them. For smd codes, there's a lot of "calculators" (resistors) or catalogs (for semiconductors) over the web. Always there's a problem with film and ceramic caps, because there's no codes at all. Usual when am modifying smd circuits i just remove capacitors and measure it.

Tonzauber,

Then I take back what I said, I have had a year off work because of a severe work injury. Seems like things changed. I knew they were going to do this to Soundcraft. Bummer

Guys it's the capsule. I tried another one, generic/chinese and the bass was there. The circuit doesn't have that much of a drop i am hearing  anyways. It's just that i have no idea why people praise this mic. Could be ok for overheads and room mics, but for this kind of money it's crap.

I just did a video shootout of some of my mics on guitar cab, C 535 is second to last. It's right on the grille and this is its maximum bass response having proximity effect in mind. For my taste it just sounds like an abortion.

https://www.youtube.com/watch?v=a3niXNz3NL8&feature=youtu.be

micaddict said:

AKG, by Harman, by Samsung has recently discontinued this mic, unfortunately.
It's a back electret condenser that's maybe not the most noiseless, but it's a classic for a reason.

Click to expand...

Actually the CE31  (in C535EB) is not a backelectret capsule. The diaphragm itself is charged! It was made from a special Teflon film with a nominal thickness of 12,7µm, manufactured by DuPont. Despite the thick film a crisp sound was archieved by adding a resonator disc in front of the diaphragm that boosts the very top end. Some other details contribute to  the fairly high detail resolution of the CE31.

I´m not surprised that Samsung discontinued the mic. There have been problems in the past to get this Teflon film in the necessary quality. When ordering such small amounts of film you really can´t do any special orders and DuPont doesn´t care if the material is going to be used to make diaphragms. It´s take it or leave it. Not a situation that an extremely profit oriented company would want to be bothered with.

A healthy C535EB is not supposed to sound thin without the LF rolloff engaged. 
I once was given a 535 with the same problem. It turned out that the diaphragm had collapsed. I disassembled the capsule to release the diaphragm from the backplate and it worked fine again afterwards. The diaphragm was faulty however. It lacked even tension and was slightly warped.

Thanks for this, i will check it out. Bass response is in the sm57 ballpark at best. Weird for an sdc anyways.

Actually the CE31  (in C535EB) is not a backelectret capsule. The diaphragm itself is charged!

Click to expand...

Interesting. From the back of my head, old catalogs said "pre-polarized".

Oh yes, the diaphragm is prepolarized.  BTW, the CK1X, CK2X, ect. are elektret too. With the same thick Teflon diaphragms. Sound quite different from the regular CK1, Ck2, ect. with it´s 3µ Macrofol diaphragms. Quite nice as spot mics.

On AKG´s backelectret capsules the same Teflonfilm is (was) molten directly onto the backplates and then charged. Those use regular diaphragm materials.

@ kingkorg:
There might be a replacement CE31 capsule available for your C535. I just have no clue about current "AKG" service departments. That seized to exist in Austria. Try your local AKG dealer.