Klark Teknik KT-2A Optical Compressor

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fazer

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Has anybody tried the Klark Teknik KT-2A Optical Compressor?  $399.00  is so cheap.    What is the opto element used?  I thought the cad opto;s were ban in EU.

Reason I ask is a new voice talent contacted me about the quality of their VO demos.  I said she needs a compressor going into the interface from the Mic preamp.  (Focusrite preamp).

I use my LA 3A for Vocals and VO's with a Neuman 249.  I recommended an LA3A  and see they are no longer made and UA LA2As are $3500.00 and TB4s are going for as high as 1000.   

I like the old  Urie 710s but don't see those much and 3As are going for 2500 on REVERB.  Are LA4A's any good.  I've never tried one.    Whats a new VO talent to do. 

Suggestions
 
Cool vid....

I'm not convinced the levels were set right???? If they were. the diy LA2A was nicer  imo......

in kingkorg's example, I liked different characteristics of both........ weird.....
 
scott2000 said:
Cool vid....

I'm not convinced the levels were set right???? If they were. the diy LA2A was nicer  imo......

in kingkorg's example, I liked different characteristics of both........ weird.....

Agree that the vids comparison has some flaws.  The DIY one has Sowter transformers too , which are known for being clean sounding.
 
I've got a few of the Klark Teknik tube EQs and compressors. Once you change the tubes in the signal path to something better (I used Tung Sol) they improve quite a bit (dirt and constricted dynamics go away). You need the right screwdrivers (Torx-T10 and T9) to open these units, BTW.

I don't believe there to be anything wrong with the audio transformers. An area of improvement would be the power supply filtering, I would prefer less residual hum. The switching supply will probably not live as long as a good linear one.

At the price these are being sold here, even with the tube upgrade, I couldn't DIY them and they are really good.
 
living sounds said:
I've got a few of the Klark Teknik tube EQs and compressors. Once you change the tubes in the signal path to something better (I used Tung Sol) they improve quite a bit (dirt and constricted dynamics go away). You need the right screwdrivers (Torx-T10 and T9) to open these units, BTW.

I don't believe there to be anything wrong with the audio transformers. An area of improvement would be the power supply filtering, I would prefer less residual hum. The switching supply will probably not live as long as a good linear one.

At the price these are being sold here, even with the tube upgrade, I couldn't DIY them and they are really good.

I’ve got to try a pair of these.  Are the tube types the same as in a LA2A.  I see a el84 that’s different but 12bh7 12ax7 are normal.
 
KT-2A:

There's one 12AX7 in the signal path, the other one is just for the sidechain. You can find out which one to replace by temporarily removing it (while the unit is turned off, obviously).

The other tube in the sidechain is the 12BH7A.
 
living sounds said:
KT-2A:

There's one 12AX7 in the signal path, the other one is just for the sidechain. You can find out which one to replace by temporarily removing it (while the unit is turned off, obviously).

The other tube in the sidechain is the 12BH7A.

It seems more sensible that the BH7 would in the audio path & in the sidechan the EL84 replaces the 6AQ5, since they are roughly the same sort of valve.  But since I don't have one I'm probably wrong about this.
 
living sounds said:
KT-2A:

There's one 12AX7 in the signal path, the other one is just for the sidechain. You can find out which one to replace by temporarily removing it (while the unit is turned off, obviously).

The other tube in the sidechain is the 12BH7A.

Or you could just look at the LA2A schematic and follow the signal path with a multi meter. 12BH7 is the output stage driving the output transformer.
 
Kingston said:
Or you could just look at the LA2A schematic and follow the signal path with a multi meter. 12BH7 is the output stage driving the output transformer.

I don't think the KT-2A is an exact copy of the circuit. But removing a tube and seeing what happened is fast and worked for me. ;-)
 
fazer said:
Whats a new VO talent to do. 
I would suggest checking Golden Age Project
https://www.goldenageproject.com/outboards-2/
I haven't myself tried their comps, but I know their preamps and EQ's and can vouch they are very close to the originals. Various surveys seem to indicate it's the case for their compressors.
 
I have a KT2A here right now. My DIY LA2A smokes it. The Klark loses lowend and doesn´t do the nice creamy lowmid color that my DIY version does (original UTC trannies + Urei T4B). Besides the difference in tone the compression behaviour is very close. Maybe the Klark is a good starting point for further improvements as it´s dirt cheap.

The LA4 is a nice compressor. I really like them. It´s very slow though. My pair has different opamps which makes them a bit cleaner. The original LA4 is no slouch either, though.
 
jensenmann said:
I have a KT2A here right now. My DIY LA2A smokes it. The Klark loses lowend and doesn´t do the nice creamy lowmid color that my DIY version does (original UTC trannies + Urei T4B). Besides the difference in tone the compression behaviour is very close. Maybe the Klark is a good starting point for further improvements as it´s dirt cheap.

The LA4 is a nice compressor. I really like them. It´s very slow though. My pair has different opamps which makes them a bit cleaner. The original LA4 is no slouch either, though.

Stock KT2a? 

Even with the differences you are saying, the DIY La2a is at least $700 in parts, so roughly double the KT2a.
 
I notice the T4B cell shown in the video of the DIY version has a CE mark on it. How does the supplier manage that considering it contains cadmium sulphide?

Cheers

Ian
 
ruffrecords said:
I notice the T4B cell shown in the video of the DIY version has a CE mark on it. How does the supplier manage that considering it contains cadmium sulphide?

Cheers

Ian
It's a long time I haven't been concerned with regulations, but isn't the presence of CdS an RoHS issue? Maybe CE is not concerned about it...
 
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