Pimp my Pro VLA

[norman_nomad]

So I decided to pimp out my lowly Pro VLA by adding new tubes as well as some nice Cinemag transformers on the inputs and outputs.

I chronicled with pics and sound samples along the way. Check it out!

[norman_nomad]

more tube samples.

(note, you'll have to adjust the Electro Harmonix tube by 0.5db to get it to match)

[norman_nomad]

input transformer

[norman_nomad]

Output Transformer.

[pianokeys]

Nice work - great samples!

[Empty Planet]

Nicely done, Norman!

I don't know if it quite convinces me to go to the trouble. Mainly because I'm just barely capable of popping out an old tube and sticking in a new one. And partly because I figure if I really want a new sound, I need a different box.

But excellent presentation, nonetheless.


Cheers.

[Dave Peck]

Thanks for the info!

Can you give a ballpark figure for how much $$ this cost you, and how many hours were involved ? Also, where did you get the info for how to wire it up?

DP

[norman_nomad]

Originally Posted by Dave Peck

Thanks for the info!

Can you give a ballpark figure for how much $$ this cost you, and how many hours were involved ? Also, where did you get the info for how to wire it up?

DP

All 4 transformers were about $150. The mullard tubes were $40 I think?

If I were to do it again, I might get some of the cheaper steel transformer to eak out a little more tone from the unit. The cinemags are pretty clean. The input transformer is all nickel and the output is half nickel/half steel. They do something nice to the low and and soften the highs just a bit, so I'm happy. But it's all very subtle IMO.

I figured out the wiring from looking at the schematic for the Pro VLA and looking at the data sheet for the transformers. I got a little confused on where to implement the output transformer so I got some help from the nice fellows on the prodigy-pro forum. I can post a wiring diagram if you wish. I'd be curious to hear this mod with different transformers.

It took me about 4 hours to do the mod, but I could probably do it in an hour now that I'm familiar with the wiring.

[third world]

i picked up the same compressor for cheap and was thinking about switching the tubes. what tubes do you recommend? i guess the mullards? and is switching the tubes a fairly simple job? i was looking at RFT 12AX7s, and am hoping they could give my drum tracks a harsher, darker tone.

the wiring diagram would be nice as well but i'm sure i won't be able to switch out the transformers by myself.

[drycounty]

BTW where did you get the Mullards? Did you get the xformers from cinemag direct? What model number were these?

GREAT post!

[norman_nomad]

I used the CMLI-15/15B for the inputs and the CMOB-2L for the outputs. I orderd directly from Cinemag.

I purchased the Mullard 12at7's from ebay.

You can check out this link for more info on wiring it up. Or if you have any direct questions, feel free to PM me.

Prodigy Professional :: View topic - Art Pro VLA - Help me add input and output transformers!

[norman_nomad]

Originally Posted by third world

what tubes do you recommend? i guess the mullards? and is switching the tubes a fairly simple job?

I've only tried mullards. You might have better luck with different tubes. I personally don't think the Electro Harmonix tubes that came with the compressor sounded that bad, although I supplied audio examples so you can decide for yourself.

The tubes are socketed so they're very easy to replace. Just make sure the unit is powered down when replacing them.

[Brad McGowan]

To my ears as you added the transformers the low end progressively got smaller in size as the subs were gobbled up by the iron. IMHO the drums had more impact and spaciousness without the transformers in the signal path. In general, the all steel input transformers will have more saturation than a high nickel transformer.

FWIW I used NOS G.E. 12AT7's in my ProVLA and found they had more high end sparkle and sheen compared to Mullards.

Nice work! Now put some better opamps in there! I bet you'll get a lot more mileage out of that than the transformers.

Brad

[norman_nomad]

Originally Posted by Brad McGowan

To my ears as you added the transformers the low end progressively got smaller in size as the subs were gobbled up by the iron. IMHO the drums had more impact and spaciousness without the transformers in the signal path. In general, the all steel input transformers will have more saturation than a high nickel transformer.

FWIW I used NOS G.E. 12AT7's in my ProVLA and found they had more high end sparkle and sheen compared to Mullards.

Nice work! Now put some better opamps in there! I bet you'll get a lot more mileage out of that than the transformers.

Brad

Word. I noticed a change in the low-low end as well. I did some sine sweeps tests though and there's no change in level going down to 20hz... so maybe this is just how the transformers react to transients or something else. Any transformer will act as a natural high-pass but it may be that the 5532 is struggling to find enough output current to properly drive the transformer...

In practice I find the unit to be less versatile then prior but with slightly more "tone". I wanted the option to overdrive the inputs on the unit so this mod allows me to do it.

The input tl072's were completely replaced and all that's left in the signal path is the 5532's on the output right before the output transformer. I may upgrade these or leave them... haven't decided quite yet.

[suiseidl]

the mullards sound a bit more "punchy" to me than the stock tubes- better transient response. the transformers however have very little impact on the sound imo.

very interesting thread- very helpful for people who are unsure about modding their vla or not!

[drastic]

Originally Posted by Brad McGowan

To my ears as you added the transformers the low end progressively got smaller in size as the subs were gobbled up by the iron. IMHO the drums had more impact and spaciousness without the transformers in the signal path. In general, the all steel input transformers will have more saturation than a high nickel transformer.

FWIW I used NOS G.E. 12AT7's in my ProVLA and found they had more high end sparkle and sheen compared to Mullards.

Nice work! Now put some better opamps in there! I bet you'll get a lot more mileage out of that than the transformers.

Brad

Hey Brad,
Just wondering where you picked up your NOS GE tubes from? Ebay? I've seen a few listed on there, but was wondering if you had a good place to purchase from? I've been thinking about changing tubes in my VLA, sounds like a nice improvement.

Thanks,
Matt

[norman_nomad]

Originally Posted by suiseidl

the mullards sound a bit more "punchy" to me than the stock tubes- better transient response. the transformers however have very little impact on the sound imo.

very interesting thread- very helpful for people who are unsure about modding their vla or not!

I also think the mullard tube made the biggest difference in the sound of the unit.

The Cinemag high nickel transformers are very clean up to their max operating voltage. You can hit the input transformers hard and get a little dirt ... if that's your thing...

You might want to consider replacing the input opamps with something a little nicer... that'd be an easy and cheap upgrade.

[third world]

anyone try using JAN Philips NOS USA in their VLAs? i'm looking for something "cleaner" than the mullards. also norman_nomad, is your model one of the older usa made ones or the newer chinese made? also what replacement opamps will work in this unit?

lol, i posted in this thread so long ago and still haven't gotten around to modding this thing.

[Brad McGowan]

Originally Posted by drastic

Hey Brad,
Just wondering where you picked up your NOS GE tubes from? Ebay? I've seen a few listed on there, but was wondering if you had a good place to purchase from? I've been thinking about changing tubes in my VLA, sounds like a nice improvement.

Thanks,
Matt

I'm pretty sure I got mine from TubeDepot.com or Thetubestore.com. I got matched and balanced triodes.

Brad

[norman_nomad]

Originally Posted by third world

anyone try using JAN Philips NOS USA in their VLAs? i'm looking for something "cleaner" than the mullards. also norman_nomad, is your model one of the older usa made ones or the newer chinese made? also what replacement opamps will work in this unit?

lol, i posted in this thread so long ago and still haven't gotten around to modding this thing.

I think mine is a newer chinese model.. I purchased it "new" right about the time I posted this thread.

OPA2604 opamps in place of the TL072's on the rear XLR pcb board. The TL072's aren't socketed so you'll need to be handy with a soldering iron.

[lozion]

Funny, both of you switched from 12AX7's to AT7's and those have less gain.
Why do you think it is a better choice? Lower gain characteristics would mean a cleaner albeit "colder" tone, no? Incidently, a quite unknown but worth checking tube company I like is made in former Yugoslavia EI Elite series. They have gold tops & I'm sure they would be good contenders for tube comps.

[Brad McGowan]

Actually mine came stock with new EH 12AT7's. I think the design changed somewhere along the way.

Brad

[lozion]

Originally Posted by Brad McGowan

Actually mine came stock with new EH 12AT7's. I think the design changed somewhere along the way.

Brad

Oh ok, my bad. I was under the impression the VLA used 12AX7's...
Could be worth trying for more gain.
Brad, I've read your reply on the unknown comp for 2 buss thread and I must say
I'm actually surprised at all the love this comp gets, I might just have to get one...

[Brad McGowan]

It's so cheap it's worth trying out right? I think once you get over the fact that it's made by ART and just try to evaluate it as another tool in the toolbox then you realize that it's actually quite a nice and useable piece of gear. I'm still fighting that bias myself. I have a Distressor and 1176 in the rack as well and I often reach for those first without even bothering to try the ProVLA, only because it's "cheap". But you know what--it's way simpler to set up and get a good sound out of for tracking. Auto attack and release pretty much work for everything you want to control the dynamics of. It's a pretty invisible compressor. I used it on some acoustic guitar yesterday and it was great.

Brad

[WunderBro Flo]

I tested three VLA units some years ago, they all had the problem that they severely distorted any signal that went in that was over +12dB (while the specs say it can handle up to +21). I was going from the DA of a 03D into the VLA and it always happened. Returned the units, dealer checked them and said that´show they all behave, nothing wrong with my unit(s). Sold them. Do they still have that headroom problem or was that a specific problem between a 03D and a VLA, or have ART fixed the headrioom issue in the meanwhile? Anyone knows?


ps - just send a sine wave through the VLA at approx. +15dB -20dB and set the threshold so there is no GR. If it is still a sine wave at the output then everything should be fine. Back then I was getting a heavily distorted wave from +12dB upwards....



Rock on!
Pat

[Halfmoon]

Look like they did some update

Buy ART Pro VLA II Tube Compressor online at Musician's Friend

[haryy]

Looks sexy, i hope they upgraded its sound also, anyway i was going to buy one and the new model arrived at the right time.



Ps. norman_nomad could you please post your original clips without the Vla ?

[WunderBro Flo]

haha, can´t wait until the first posting show up saying the discontinued "vintage" ProVLA sounded way better than the new ProVLA II.....let´s place some bets.....I say in less than 4 weeks we will have the first ones....


Rock on!
Pat

[haryy]

Anyone knows a place in EU for buying or preordering?

[muziekschuur]

I'm listening on a laptop to this material and I hear a difference. Nice. It went from a nice compressor to a really nice compressor.... Allmost great...