Klark Teknik KT-2A

[Whoops]

I want to replace all the weak points of the machine

Is the PSU a weak point in the KT-2A?

Thanks

 

[abbey road d enfer]

Is the PSU a weak point in the KT-2A?

+1

 

[FarisElek]

Minor capacitor upgrades, and drip in optocell, and tubes is one thing. But, building a linear PSU is getting to the point in which you should probably sell the Klark Teknik and spend the money you want to use for modifications to build a clone yourself with all the parts you most desire. There is lots of opto builds on this forum.

 

[abbey road d enfer]

But, building a linear PSU is getting to the point in which you should probably sell the Klark Teknik and spend the money you want to use for modifications to build a clone yourself with all the parts you most desire.

The main point here is that no significant improvement is to be expected from replacing the PSU.
Today, for a designer, using an smps instead of a linear is not a matter of cutting cost at the expense of any loss of performance, it's just the way to go, as long as certain precautions are taken.

 

[FarisElek]

The main point here is that no significant improvement is to be expected from replacing the PSU.
Tosay, for a designer, using an smps instead of a linear is not a matter of cutting cost at the expense of any loss of performance, it's just the way to go, as long as certain precautions are taken.

Totally agree. I like Linear PSU's. But I don't think it's a flaw in this unit.

Ryan

 

[abbey road d enfer]

Totally agree. I like Linear PSU's. But I don't think it's a flaw in this unit.

Ryan

In all honesty, I wouldn't be capable of designing an efficient smps, but good ones are commonly available and cheap.
When I replaced the linear psu with a bunch of these little 24V smps, in my latest build, I couldn't detect a iota of difference between them.
Also I have two 51X racks, one that uses the silentarts (linear) PSU and another that I power with 4 MeanWell smps and a DC/DC converter for phantom; I can't tell the difference between them in operation.
There's an old saying that goes "Everything is in the signal path, including the PSU". I never forget that, but it's important to know exactly which part of the PSU actually affects the signal and how. Power amps and "brute force" DOA output stages actually depend very much on their PSU for proper performance, but any well-designed low-power piece of gear relies on proper local decoupling.

 

[[email protected]]

ok, thank you for your advice!!

 

[PG_Sax]

I have just finished a few upgrades on my KT 2A. I originally bought it around a year and a half ago with the idea of slowly changing bits and pieces to see what would happen.

I first changed the tubes and the photocell this was shortly after I got the unit.

Tubes - RCA / Telefunken - only audio path tubes.

Photocell - IGS

I have just changed the coupling capacitor and the transformers. Mundorf / Sowter.

I will post files to see what people think.

 

[dickiefunk]

I've just ordered some Harma tubes for my KT-2a. Still torn which optocell to get.  I found another comparison of the Black Lion T4bla against the stock T4. Here is the link :-

https://drive.google.com/drive/folders/16_CwJ1MHZlQyyP4p5luIYNqrNVdOgg3p?usp=sharing

Which clip do you prefer?

 

[vintagelove]

I've just ordered some Harma tubes for my KT-2a. Still torn which optocell to get.  I found another comparison of the Black Lion T4bla against the stock T4. Here is the link :-

https://drive.google.com/drive/folders/16_CwJ1MHZlQyyP4p5luIYNqrNVdOgg3p?usp=sharing

Which clip do you prefer?

I imagine a is the stock cell? It sounds more relaxed.

Honestly, who wouldn’t want them a switch. That being said, for what I bought it for, which is a clean/quiet optical compressor, i’m happy keeping the stock unit until Uri decides to put out a three pack for 50 bucks...

 

[demode_iowa]

Kenetek T4B VS KlarkTeknik Stock
https://www.youtube.com/watch?v=afDRlX3F0EA

 

[Rocinante]

I really like the Kenetechs. Plus he's a good dude and contributor here and his T4B's are really that good.

 

[cassio2263]

Hi,
Do you recommend another brand of polypropylene capacitor?
I'm not finding Solen in Brazil.
I actually found one with 10uf/630v (must be pretty big).

Has anyone done the test with the original Urei T4b cell?
I bought one. I'm waiting to arrive.
Another question = what brand is the big yellow capacitor on the Klark teknik audio output?

Thanks.

 

[Whoops]

Hi,
Do you recommend another brand of polypropylene capacitor?

There's a lot of different brands of good polypropylene capacitors like WIMA, Panasonic, Vishay.

But the question is, does changing film capacitors gives any improvement?

 

[cassio2263]

There's a lot of different brands of good polypropylene capacitors like WIMA, Panasonic, Vishay.

But the question is, does changing film capacitors gives any improvement?

I do not know that.
I'm following the advice of some - replace the big yellow capacitor (10uf/250v).
I also want to replace the 12ax7 tubes. I found in Brazil miniwatt philips tubes manufactured here. They say it has the same quality as the philips made in Holland.
I have T4b urei, genuine, to install too
Greetings.

 

[JMan]

I think that's probably C5 (in the original unit), and people seem to like subbing/swapping/rolling that cap, as it is the one that is supposed to have the most significant impact on actual sound. You could go with any of the brands of polypropylene caps that Whoops mentioned above, or you could go with Sprague, or even something super fancy like a Mundorf Supreme.

I don't know what differences there are in the KT vs the original, but make sure it has a sufficient voltage rating -- I might be wrong, but I want to say that the cap in the original is rated at something like 400v. Of course, something like the Mundorf (which is rated considerably higher) will work just fine too. Probably 250v is okay in the KT version if that's what comes stock.

 

[skipwave]

I have a KT-2A (edit: strike that, reverse it - correct model is 2A-KT) I replaced the gain stage 12AX7 with a Mullard reissue and there was a very noticeable improvement in fidelity.

after checking out the Black Lion Audio comparisons I ordered the T4BLA. I’ll make my own comparison and post.

If anyone has an audio file they want to hear as additional before and after samples, DM me and I’ll invite you to a shared folder to upload it to and I’ll run it through.

 

[living sounds]

So, in addition to the signal path tube upgrade I replaced the Behringer T4B with a Kenetec classic variant and replaced the yellow poly cap with a Solen Fast.

I've got two compressors, so I was able to compare directly, matching closely via cancellation with inverted signals. Huge difference!

The compression behaviour of the original is very nervous and obvious in a negative way compared to the Kenetec T4B.

The bass is full and authoritative with nicely controlled punchy attacks in the fully modded compressor. And it has the signature smoothly balanced "LA-sound" the LA2A is famous for.

The other one sounds lacks some of the low end punch and distorts very obviously at higher amplitudes and sounds strained in the mids and brittle in the highs.

I had not hoped for this much of an improvement, but this really made all the difference. The fully modded compressor is up there with the best tube compressors now.

And again, do not touch the transformers, they sound great!

Measurements show a little more low end distortion in the unit with the original cap and T4B, but this might not have anything to do with the changes. I'll have a look again after modding the second unit.

 

[PermO]

So, buy a unit, swap the TB4 cell, get some nice tubes and ditch the big output cap and I will have a nice La2a ?

Could never DIY one at that pricepoint, case, transformers, knobs, meter, no way.. So these cheap clones may be a blessing after all ?

 

[living sounds]

So, buy a unit, swap the TB4 cell, get some nice tubes and ditch the big output cap and I will have a nice La2a ?

Could never DIY one at that pricepoint, case, transformers, knobs, meter, no way.. So these cheap clones may be a blessing after all ?

I've got no real LA2A or high quality clone to compare to, but the modified KT is right up there with the best vari-mu, opto, VCA, FET and diode compressors I own. Even with the upgrades it is as inexpensive as DIY and all the mods can be done in half an hour (that includes cleaning the PCB around the signal path tubes from solder flux).