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ART VLA PRO II Kenetek Mod Vs. Stock Dynamics Processors (HW)
Old 3rd October 2008
  #1
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ART VLA PRO II Kenetek Mod Vs. Stock

Hello Gearslutz,

Okay, I like to begin and say that I really like the VLA PRO II for what it does and how much it cost. $250 stock price. Stupid cheap and able to get pro results. A Dual stereo Vactrol Tubed Leveling Amplifier with detented pots, stereo link, adjustable attack and release. Big improvement over the first VLA pro 1. Better quality overall that the VLA PRO I. Others have mentioned that the VLA does great on Overheads, Acoustic guitar and Voice in particular. I concur.

I recently replaced my LA-2A reissue with my new modded Kenetek VLA PRO II since it much more versatile and now has that vintage IRON (Think LA-2A) transformer mojo now. Don't misunderstand me, I like the LA-2A reissue on certain sources and its built much better than this overall. But the LA-2A reissue is over 10 x the cost of a $250 VLA pro. $3000 Compressor that I only use on for one or two things (bass, vox). I am a frugal gear head and it was also a little too smooth/thick for my taste to be honest. I actually like the 1176LN or LA3A reissues much more than the LA2A reissue. Love original vintage Urei even morel. Finally and most importantly, the VLA PRO sounds competitive stock or modded. Its a good deal, especially for those who don't have the thought to spend 3K on a limiter. So I thought I share this to you all.

Anyway, so for the love I have for both of these compressors, I asked Bill Jones of Kenetek Pro Audio (an LA-2A, 1176 Pro builder, guru and repairman) if he could possible mod my VLA Pro II for me with some Original LA-2A transformers. I told him I was searching for a pro to do this job and I thought he would be the perfect tech to do this small project/experiment of mine. Check out his website if you haven't, Kenetek Pro Audio and the cool gear he makes. My first impression of his compressors were like "Whoaa" check out the quality work! The Kenetek 1176LN and LA2A cloned compressors looks really gorgeous.

At first, I asked if he could put the input and output transformers in my VLA like the original LA2A. But he said truthfully, that the output transformers doesn't really contribute alot for the sound. Its the input transformer on most part. So that save me some bread. Also, he asked with excitement, if I wanted the stock bypass switched to be modded so that when you engage the bypass on the compressor would switch back to the stock no transformer mode. I was like "awesome!" Please do it! Transformer on or off. Something like the Shadow Hills Gama .

But later, he suggested not to do this because of the high labor cost. But it can be done if you want it. Anyway, I bypass my inserted compressors within Protools, so the bypass switch for me is useless. So this option to change the function of the bypass switch was way cool.

But, after I compared the stock VLA PRO II to a my new modded VLA PRO II with a pair of vintage Stancor WF-30 transformers. I am glad I didn't waste his time and my money on that. Also to enhance the overall sound, I took out the stock chinese Ruby tubes, and puts some german made NOS Telefunkens (ECC83s). Nice improvement over the ruby tubes.


So after Bill agreed to do the job for me, I sent my brand new VLA PRO II to Bill Jones of Kenetek Pro Audio and emailed him the schematics.

I like to say thank you to norman_nomad (GS member) and Black Lion Audio for the schematics. norman_nomad has done this mod first with cinemag transformers and posted it here on GS. I opted to make my VLA PRO II more on the vintage LA-2Aish side by buying some vintage WF-30 Stancor transformers (WF-30 is as same as UTC A-20). They can be found on Ebay for $120 a pair. Of course UTC will cost you more than the Stancors due to its popularity.


This is what Bob stated to me in an email on transformer choices:


"I get more calls for the original HA-100X and A-24 transformers than any
other combination. However, to my ear, there is no sonic difference
between the HA-100X and the A-10. This is probably because they are
basically the same transformer internally. The big differences are the
shielding, which isn't needed in a modern recording studio like it might
be in a 100kW AM transmitter shack. My favorite input transformer for
the LA-2A is the Stancor WF-20. It has more "good" distortion to it
than any other I've heard. Jensen probably makes the "highest fi"
transformer of all mentioned, so you might try replacing the input
transformer with a Jensen equivalent. Again, without seeing (and
hearing) the unit this is all conjecture." Bill Jones



After Bill received my VLA, he had it for a few days and sent it right back to me. I was impressed with the turn around time and the quality work.

Okay, so now the goods. I am sure everyone wants to hear the difference from the stock VLA.

Let me start to say, first of all, what you are about to hear was done very quick and rough for a good reason. The purpose of these sound files is to hear the difference of the VLA stock version compared to the VLA Kenetek mod. Thats it. I added it on one of my songs that I working on right now in the tracking phase. Mixbuss, drum buss, and acoustic guitar. Sorry, folks no time for vox, or bass guitar. But I assure you, the VLA pro is my favorite for vox. I personally liked it on lead vox more than the LA-2A and CL1B that I have tried in my studio.

We quickly slapped the VLA really quick to get an idea what this modded VLA can do after receiving it from Bill. So take that in consideration. I hope that with your system you can hear the subtle differences on these mp3 files.

I took to time to post these files because I am a very satisfied customer of Bill Jones (Kenetek Audio). And I thought it would be nice to share the results with budget minded Gearslutz. Personally, I am always in search for good gear that doesn't cost the same as a down payment for a new home. thumbsup Bill has definitely tuned up my VLA pro II. I definitely hear the difference between the stock and after modded VLA. My stock VLA is out of my studio and the Kenetek mod has taken over.


Before I even thought about posting this, I asked Bill if he would mind if I posted some sound files of the unit. He was cool about this. And he said that he wouldn't mind doing a few more VLA's if anyone is interested. Bill charged me $250 for the labor which I thought was a nice deal. The transformers cost me $125 used on Ebay, the telefunken NOS ECC81s cost me $65 a pair on Ebay. So total cost for me was $450 for this compressor. Which was an awesome deal for me. I think after modification, the VLA pro II stands up against some of the popular comps out there 5-10x its cost, and I now find it more usable than the stock for the mix bus/drum bus since it now adds some punch on the lowend and mojo sparkle on the high compared to the stock version.


Enjoy.
Attached Thumbnails
ART VLA PRO II Kenetek Mod Vs.  Stock-img_0232.jpg   ART VLA PRO II Kenetek Mod Vs.  Stock-img_0229.jpg  
Old 3rd October 2008
  #2
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Zip file says it's corrupt and won't extract.
Old 4th October 2008
  #3
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Hmmm strange

When I log out of GS, I can download it fine and expand it with no problems over and over again. I just checked it for you. I am using a Mac, with Stuffit expander version 12. Try the stuffit expander. I think its free.

Otherwise, I don't know what else I could tell ya.
Old 4th October 2008
  #4
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Talking Methinks...

That you may have a cool product there after the mods.

My questions center around how inserting the input transformers into the actual PRO VLA II circuit right at the inputs is any different than just throwing those UTC transformers in a little box and connecting up a pair of input jacks and output jacks to the correct taps on the transformer?? Running the audio thru that and then into the PRO VLA?

Since the trafos don't become part of the compression scheme they are simply there to flavor the signal, it seems thats all they really do is just flavor the audio.

I am not criticising your choice here just putting out a perspective that since you had those UTCs at your disposal you might end up with something a little more flexible because you can use the UTCs or not if they are in a box you can patch in and out.

It is cleaner to have them inside the ART if that's the only place you're going to use them or need them for. But the UTCs are some pretty nasty good IRON its a shame to see them dedicated to only one unit.

You mentioned that the ART is competitive with higher priced units at this point. So will you be selling them now? Or is it just a better tool at this point.

I own the original PRO VLA and have considered building a little transformer box to put before the VLA just for ****s and giggles.

I mean when you think about it, you could use the transformers for anything like A/D or D/A for that matter.

But cool project.

Looks good can't wait to check out the audio.

Peace
Illumination
Old 5th October 2008
  #5
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Nice work DONNX!! The modded version with the Stancor's sounds awesome! Way more vibe and low end punch!
Old 5th October 2008
  #6
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peeder's Avatar
 

Well if techs advised their clients to do something as sensible as that they wouldn't sell many mods. This way they can sell more than one trafo mod to the same customer.

Quote:
Originally Posted by illacov View Post
That you may have a cool product there after the mods.

My questions center around how inserting the input transformers into the actual PRO VLA II circuit right at the inputs is any different than just throwing those UTC transformers in a little box and connecting up a pair of input jacks and output jacks to the correct taps on the transformer?? Running the audio thru that and then into the PRO VLA?

Since the trafos don't become part of the compression scheme they are simply there to flavor the signal, it seems thats all they really do is just flavor the audio.

I am not criticising your choice here just putting out a perspective that since you had those UTCs at your disposal you might end up with something a little more flexible because you can use the UTCs or not if they are in a box you can patch in and out.

It is cleaner to have them inside the ART if that's the only place you're going to use them or need them for. But the UTCs are some pretty nasty good IRON its a shame to see them dedicated to only one unit.

You mentioned that the ART is competitive with higher priced units at this point. So will you be selling them now? Or is it just a better tool at this point.

I own the original PRO VLA and have considered building a little transformer box to put before the VLA just for ****s and giggles.

I mean when you think about it, you could use the transformers for anything like A/D or D/A for that matter.

But cool project.

Looks good can't wait to check out the audio.

Peace
Illumination
Old 5th October 2008
  #7
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DONNX's Avatar
 

Quote:
Originally Posted by illacov View Post
That you may have a cool product there after the mods.

My questions center around how inserting the input transformers into the actual PRO VLA II circuit right at the inputs is any different than just throwing those UTC transformers in a little box and connecting up a pair of input jacks and output jacks to the correct taps on the transformer?? Running the audio thru that and then into the PRO VLA?

Since the trafos don't become part of the compression scheme they are simply there to flavor the signal, it seems thats all they really do is just flavor the audio.

I am not criticising your choice here just putting out a perspective that since you had those UTCs at your disposal you might end up with something a little more flexible because you can use the UTCs or not if they are in a box you can patch in and out.

It is cleaner to have them inside the ART if that's the only place you're going to use them or need them for. But the UTCs are some pretty nasty good IRON its a shame to see them dedicated to only one unit.

You mentioned that the ART is competitive with higher priced units at this point. So will you be selling them now? Or is it just a better tool at this point.

I own the original PRO VLA and have considered building a little transformer box to put before the VLA just for ****s and giggles.

I mean when you think about it, you could use the transformers for anything like A/D or D/A for that matter.

But cool project.

Looks good can't wait to check out the audio.

Peace
Illumination


Nice points. That would be a nice product. A transformer box that you could add to anything. That goes back to the old school guys running the 1176LN with no compression to the LA-2A. Just for the flavor they get from the 1176LN transformers combined witht the LA2A electronics. Same technique I think. B2 bomber new A/D is doing that sort of thing. His UA 2192 designed converter with custom transformers built in. Basically, what it is. But with converters, I personally rather have a pure clean signal. The questions you have are more for Bill Jones arena, I would think. Maybe he will chime in later.

I would love to keep the LA-2A (reissue). But for what it does, I rather use the the extra $ for other things in my studio. Thats my reasoning.

Well, if I ever needed some of that UTC or Stancor vibe, I just run it through my pimped VLA. Simple, with no compression. Just to get that color. I don't see why I need a dedicated box for the UTC vibe.
Old 6th October 2008
  #8
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norman_nomad's Avatar
Quote:
Originally Posted by illacov View Post

My questions center around how inserting the input transformers into the actual PRO VLA II circuit right at the inputs is any different than just throwing those UTC transformers in a little box and connecting up a pair of input jacks and output jacks to the correct taps on the transformer?? Running the audio thru that and then into the PRO VLA?
The reason this is not an equivalent solution is because the input transformers replace the TL072 opamp stage at the input of the Art Pro VLA which is arguably the unit's sonic weak point. Also a transformer box would not allow you to "drive" the transformer as it is likely you'd clip the opamp before you actually started to saturate the transformer.

A dedicated transformer box is a fun idea, but there's something to be said about having everything set up the way you like it in one dedicated box.... I'll take work flow over a glut of options any day of the week.
Old 6th October 2008
  #9
I just tried downloading the ZIP both ways and neither worked. Can you just upload the mp3s please?

I have a VLA II in the mail...

=)
Old 6th October 2008
  #10
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mamm7215's Avatar
Can we get a schematic or instructions on how to do this. I'm sure there's a Cinemag or Jensen equivalent. This sounds like it may be the diy of the day for this box.
Old 6th October 2008
  #11
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Talking You sure he wired it the way you did though???

Quote:
Originally Posted by norman_nomad View Post
The reason this is not an equivalent solution is because the input transformers replace the TL072 opamp stage at the input of the Art Pro VLA which is arguably the unit's sonic weak point. Also a transformer box would not allow you to "drive" the transformer as it is likely you'd clip the opamp before you actually started to saturate the transformer.

A dedicated transformer box is a fun idea, but there's something to be said about having everything set up the way you like it in one dedicated box.... I'll take work flow over a glut of options any day of the week.
We're talking a 1:1 trafo running 600:600.

In the pictures, I dont see anything other than him running a detour thru the transformers and back into the same pathway. Maybe its the picture, I remember that you said in your mod you bypassed the opamps.

If you don't mind me asking, why would you clip the opamps? Before the transformer?

Versus in your description the trafo replaces the opamp stage and then goes along the regular signal path.

Wouldnt this depend one what the opamp clips at??

a 1:1 trafo takes voltage in equivalent voltage out I thought.

So even if I send in 5 volts , 5 volts should come out.

Question arises though that the trafo is the ULTIMATE determining factor here.

If you got a nasty steel transformer in the pathway where its taking full load then its going to start distorting or coloring the audio alot sooner than a Cinemag model that wasn't marketed for color.

Push came to shove couldn't you use a stepdown transformer if you are worried about the opamp clipping??

I mean I already know folks who have built these boxes and have used them for this very purpose. Perhaps its more about the VLA but I guess you may add some more insight into this matter??

Why didn't you perform this mod on your PRO VLA??

Is the circuit design that different from version 1 to 2?? As far as the input stages??

I gotta look at that schematic again I guess.

Peace
Illumination
Old 6th October 2008
  #12
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Talking I noticed you mentioned...

Bypassing the I/O board almost entirely and just patching into the ribbon cable.

Perhaps this might explain some of the "subtle" results, versus the immediate results you sought Norman??

I almost expect though that it should be as simple as blaming the trafos for the performance.

The modded VLA II samples are night and day. Yours I can barely tell a difference if any.

This is with and without wearing headphones.

I almost wonder if we take a closer looksy....


Hmm...yeah it looks almost for certain like its your choice of trafos.

The Kenetek mod I noted just does the input section, so again, what we're working on here at this point is pre compression flavor.

What I'm still mucking on about at this point is are those opamps really going to clip earlier than the Stancors will start distorting?

If this is true could we not pad down the output of our transformer box in question with resistors????
Thus avoiding clipping the opamp??

Did the Kenetek mod bypass the opamps is the the other question cuz I can't tell really too much of anything now that I look at those picks again!

EDIT: Ok so I see what he did here. I had to zoom this picture in really really close up but I caught it or at least some of it.

He snipped that white wire off the ribbon and tied it in with the output from the transformer. Hmmm..

This is really beginning to point a finger at the transformers.
I'm just going to sit here and wait.....heh

Peace
Illumination
Old 6th October 2008
  #13
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Quote:
Originally Posted by illacov View Post

If you don't mind me asking, why would you clip the opamps? Before the transformer?

Versus in your description the trafo replaces the opamp stage and then goes along the regular signal path.

Wouldnt this depend one what the opamp clips at??
Every transformer has a max operating level. If the max operating level of the transformer is higher than the max operating level of the opamp input stage you'll clip the opamp before you start saturating the transformer. The max input level of the Pro VLA is +20dBu. This is assuming that you're running your audio into the transformer and THEN into the opamp rather than bypassing the opamp like I did in my mod. Generally opamp clipping sounds really bad.... where as transformer saturation arguably sounds better and can be used for artistic affect.

Quote:
Originally Posted by illacov View Post

If you got a nasty steel transformer in the pathway where its taking full load then its going to start distorting or coloring the audio alot sooner than a Cinemag model that wasn't marketed for color.

Push came to shove couldn't you use a stepdown transformer if you are worried about the opamp clipping??

A steel transformer or an older transformer is certainly going to sound different than a top tier Cinemag or Jensen.

You could use a step down transformer before the opamp stage if you wanted to saturate the transformer with out clipping the opamp... but if you're going to go through all the work or adding a transformer on the input, it's probably best to just remove the opamp stage entirely.
Old 6th October 2008
  #14
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Quote:
Originally Posted by illacov View Post
Perhaps this might explain some of the "subtle" results, versus the immediate results you sought Norman??

I almost expect though that it should be as simple as blaming the trafos for the performance.

The modded VLA II samples are night and day. Yours I can barely tell a difference if any.

This is with and without wearing headphones.
The Stancor's, to my ears, sound to be a really good choice for this box if you're looking for some extra grit/personality.

I agree that with the Cinemags the difference was very subtle. The Cinemags are doing exactly what a modern well built transformer is supposed to do: pass audio with very little degradation.

If I were to do the mod again I'd go with something older and dirtier because the Pro VLA circuit is already fairly clean (albeit with a little bit of tube blurring that comes from running the tube below it's intended plate voltage).

Quote:
Originally Posted by illacov View Post

What I'm still mucking on about at this point is are those opamps really going to clip earlier than the Stancors will start distorting?
Again it all depends on the max operating level of the transformer and whether you intend to hit the transformers hard.

Quote:
Originally Posted by illacov View Post
If this is true could we not pad down the output of our transformer box in question with resistors????
Thus avoiding clipping the opamp??
Sure, you could build some simple 10 or 15db pads into your transformer box. Purists would still have a problem with running the audio through the TL072's however.

Personally I wouldn't have an issue with it. TL072's when implemented well can sound OK. My biggest argument for keeping them in the same box would be work flow.
Old 7th October 2008
  #15
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Talking On a truly geeked out note!

Ive decided to perform this mod myself on my own PRO VLA version 1.

Mine has the EH tubes in it.

I spoke a bit via PMs with norman and one of the things I would really liek to explore is the fact that there's tons of room on the left side of the PRO VLAs interior opposite to where Kenetek installed the Stancors.

Automatically I went ahead and ventured that another set of trafos can be installed in there!

SO my working idea is that I will have 2 sets of transformers in the PRO VLA and that you can switch between them on the inputs for variable flavor.

The premise being, that the mod only addresses using the XLR inputs and leaves the TRS jacks out of use.

Two things arise because of this.

A) What if you don't use the XLR jacks in the first place on your PRO VLA?

B) What can we do with that other set of unused TRS jacks??

Here's my solution:

You can remove the XLR input jacks from the schematic totally on the inputs. Replace them with TRS jacks and wire them directly to the transformers you install for choice 1. You may have to drill some new holes or not, depending on how you mix it up.

You can wire the unused set of TRS jacks (inputs) to another set of transformers, of your choosing.

In this scenario, lets say choice 1 is Tamura transformers and choice 2 is Stancors.

Where the wonderment happens is that simply by switching your inputs, so instead of plugging into the 1st set of trs inputs, you plug into the second set, you are accessing the other transformers.

The only thing thats needed at this point to address the outputs from the transformers is a switch/switchable junction. EDIT: MY ignorant self has found out the switch type is a SPDT switch aka Single pole dual throw. Pretty simple implementation too.

You would take the + output from each set of transformers, route them to the junction and then when you are using choice 1 you switch to choice 1 on the switch, when you use choice 2 switch to choice 2 on the switch.

4 different flavors of compression in one box!

Awesome!!

Thanks to DONNX and norman for helping me out with this. Thanks to Kenetek for their great work.

I may buy a 2nd PRO VLA because of this and put 2 more sets of different transformers in that one too!

Peace
Illumination
Old 7th October 2008
  #16
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If you're going to put two different sets of transformers on two different jacks, you don't need a switch!
Old 7th October 2008
  #17
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Talking Ok, less work??

Quote:
Originally Posted by norman_nomad View Post
If you're going to put two different sets of transformers on two different jacks, you don't need a switch!
So you just tie both sets of + outs from the transformers to the channel buffer then??

This wouldn't cause any impedance issues would it?? Just curious.

I figured the switch would be easier.

Another question would be then.

A person like me who doesn't use the VLA in stereo.

If we have 4 sets of inputs, then why not 4 different transformers??

Hmm..

So what if you wanted 4 different choices on one jack?? But didn't want to deal with repatching??

Would a switch be better then?

So for example I just plug into input 1 (replaced with TRS jack). What kind of hookup would a person need to switch between 4 sets of transformers??

Would it be a 4 position switch or something like that with the common being the input side of the TRS jack with + and -?? The 4 different positions routing to the primary side of the transformers with + and -??

So whats a clean way to tie those + outputs from the transformer?? a 4 to 1 junction or something like that??


That indeed would be a monstrous compressor. 4 different flavors on each channel.

Truly you could configure it whatever way you wanted.

Hell you could do 8 different transformers, if you really wanted to go bananas.


I'm leaning towards the 4 same transformers each channel, with the idea that if I want I can have say like the same flavor on bass that I have on vocals.

Any thoughts, suggestions? Contributions??

Peace
Illumination
Old 9th October 2008
  #18
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DONNX's Avatar
 

You guys are developing a new product cool.
Old 10th October 2008
  #19
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I just wanted to chime in here with a few clarifications; I'm the tech that did the work on Don's VLA. First, the reason the trafos are mounted on the right side of the box is twofold. First, to keep them as far away from the power transformer and AC leads as possible. Second, by mounting them to the side of the box, it keeps the screw heads from scratching other gear as you slide the unit in and out of the box.

The transformers completely bypass the IC op amp input stages, eliminating a lot of cheap Chinese components as well as the IC's. The circuit, btw, is screwey and not exactly balanced because one of the op amps is also being used for the unbalanced inputs.

I wired the Stancors 1:2 to try to eliminate the 3 dB loss Norman reported in his Cinemag-modded unit. According to Don, the unit actually has *more* gain than a stock VLA.

Finally, the Stancor's *aren't* the same as UTC A-20's, although they have identical winding ratios. The Stancor's have way more vibe - all good - and are amongst my favorite of all transformers, even modern varieties.

Okay, one more thing, I kept the input boards intact and in the unit just in case Don wanted to try any other mods that might require them. My mods are minimally invasive - just a couple of wires cut here and there.

Thanks,

Joe
Old 10th October 2008
  #20
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Talking Hmmm...

Quote:
Originally Posted by joe-electro View Post
I just wanted to chime in here with a few clarifications; I'm the tech that did the work on Don's VLA. First, the reason the trafos are mounted on the right side of the box is twofold. First, to keep them as far away from the power transformer and AC leads as possible. Second, by mounting them to the side of the box, it keeps the screw heads from scratching other gear as you slide the unit in and out of the box.

The transformers completely bypass the IC op amp input stages, eliminating a lot of cheap Chinese components as well as the IC's. The circuit, btw, is screwey and not exactly balanced because one of the op amps is also being used for the unbalanced inputs.

I wired the Stancors 1:2 to try to eliminate the 3 dB loss Norman reported in his Cinemag-modded unit. According to Don, the unit actually has *more* gain than a stock VLA.

Finally, the Stancor's *aren't* the same as UTC A-20's, although they have identical winding ratios. The Stancor's have way more vibe - all good - and are amongst my favorite of all transformers, even modern varieties.

Okay, one more thing, I kept the input boards intact and in the unit just in case Don wanted to try any other mods that might require them. My mods are minimally invasive - just a couple of wires cut here and there.

Thanks,

Joe
Care to share anything else about the mod??
What about the idea of adding more trannies??

There's some real estate in there no doubt, perhaps size is the issue, but what about that running trannies in parallel on the channel buffer? Also any foreseeable issues? We're trying to add another set of transformers so that the Pro Vla would have two flavors of transformer on each channel.

BTW you said you wired the Stancors which are 1:1 (I thought) as 1:2. Ok I'm not an expert, is it something about this matching transformer as far as pinout where you can accomplish that?

Peace
Illumination
Old 10th October 2008
  #21
Gear Nut
 

Great samples DONNX!

I was wondering how would Jensen JT-11-P1 input transformers compare to Utc and Stancors? I guess more in the transparent side.

I'm definitedly interested in this mod for Pro VLA II. Any chance for a schematic for this mod?

Thanks!
Old 10th October 2008
  #22
Gear interested
 

A schematic would be WONDERFUL. I have a pair of WF 30's from an old HAM radio sitting around gathering dust and I'm already an avid fan of my VLA Pro II.

To bypass the TL072 op-amp stage I would assume it best to splice into pin 1 of JP2 (the white wire on the ribbon cable), but that's as much as I've been able to figure out on my own so far...

-Lance
Old 11th October 2008
  #23
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I'll post some DIY info about the mods when I get back home from helping with the hurricane Ike clean-up. It might be a few weeks but I'll get to it. I don't have access to any of my documentation down here.

---Joe
Old 11th October 2008
  #24
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Here's how I did my mod (if memory serves) ....

This is the easy way to do the mod... but you'll lose the TRS inputs + the bypass won't work unless you run additional wires to the bypass input +/- on the ribbon cable.

Old 11th October 2008
  #25
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Talking So I've decided to skip the switch and go ghetto.

What I'm going to do is just wire up two sets of trs jacks to two different sets of transformers.

So 4 TRS jacks to 4 transformers. Yes the repatching will be a pain but ditching the switch is one less headache.

I will probably have to install 4 new TRS jacks and ditch the old ones.

The new ones will just be wired directly to the trannys.

Very nice.

Now to get the transformers.

Peace
Illumination
Old 11th October 2008
  #26
Lives for gear
 

Thumbs up

nice test , thanks
Old 29th October 2008
  #27
Lives for gear
 
DONNX's Avatar
 

You are very welcome!

Old 30th October 2008
  #28
Lives for gear
 
WunderBro Flo's Avatar
Hi guys, just bought a MkII and found this thread...however it seems like the audio examples stock vs. modded have vastly different compression settings. One can even see it without listening, just by looking at the waveforms of the drums for example, the thresholds are not in the same spot. And they seem to be either clipping or heavily brickwall limited....it´s not really valid to draw conclusions on the sound of the modification me thinks....or did I download "broken" files?
Best,
Pat
Old 20th February 2009
  #29
Lives for gear
 
DONNX's Avatar
 

Bump for a great compressor tech and maker!

Still use it on tracking. Awesome upgrade and an unique color to the tracks.

thanks Bill (Kenetek)
Old 24th February 2009
  #30
Gear addict
 
joe-electro's Avatar
 

I have a brand new ART Pro VLA II with the input transformer mods already done up for sale on Ebay. Here's a link:

ART Pro VLA II Tube Compressor Limiter w/ Kenetek Mods - eBay (item 250378842065 end time Mar-02-09 15:24:30 PST)

Thanks!!!

Bill
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