Burr-Brown Op-amp mod for Presonus MP20 Mic Preamp

gearboy · Post by **gearboy** » Fri Jun 02, 2006 3:10 pm

I performed this mod today in 10 mins. The price for four Burr Brown OP627A op-amps through digi-key was $18 each. If you own an MP20 you have to do this mod. It really makes this preamp shine. The op-amps are easily located and snap in like tubes. No soldering.

So far all I've run through the MP20 since modding is my P-Bass, but I can already tell the difference. The mod adds clarity, presence, and a 3-D quality that the standard op-amps really lack. Totally different animal now.

Also, Jenson has a special deal for all Presonus MP owners. $30 per transformer plus $25 to install and ship back to you. I've heard that the Jensons transformers sound better for recording some instruments (esp acoustic guitar), though the BB op-amp mod is a much more drastic upgrade to the MP20's sound quality.

Can't wait to compare it to my new Sytek MPX-4Aii once it arrives.

Jeff

jmoore · Post by **jmoore** » Wed Jul 25, 2007 9:24 am

I've got an old MP20 that I'm looking to modify. I'm having trouble finding anybody who still has the OPA627AP's in stock. Any suggestions?

BradLyons · Post by **BradLyons** » Wed Jul 25, 2007 9:36 am

Yeah, it really does make a difference. To any of you Eureka owners, you'll especially notice it in the compressor!

jmoore · Post by **jmoore** » Wed Jul 25, 2007 2:15 pm

BradLyons wrote:Yeah, it really does make a difference. To any of you Eureka owners, you'll especially notice it in the compressor!

I've read nothing but great reviews about this modification, but I can't find anybody who's got the op-amps in stock. Apparently TI doesn't expect to be shipping anymore units before '08.

BradLyons · Post by **BradLyons** » Wed Jul 25, 2007 2:49 pm

jmoore · Post by **jmoore** » Thu Jul 26, 2007 10:29 am

Alright, so I found a company that has the OPA627AP in stock. The problems is that I have to order a minimum of 20 before they will accept my order. I only need four for the modification. Anybody else looking to buy some? They only want $16/ea.

gearboy · Post by **gearboy** » Fri Jul 27, 2007 7:23 am

I see eBay in your future.

jmoore · Post by **jmoore** » Fri Jul 27, 2007 11:16 am

gearboy wrote:I see eBay in your future.

I tried that. I couldn't find any. I actually have been dealing with Chad over at Presonus for the last couple of days and he and I are going to go in together to buy that lot of 20 chips. He's got four mp20's that he has been wanting to upgrade and I'm gonna buy four of the op-amps from him.

gearboy · Post by **gearboy** » Fri Jul 27, 2007 2:10 pm

Awesome! Those guys are really nice. I've met Rich a few times.

I was actually suggesting selling the other 16 on eBay. But sounds like this is going to work out well for you. PM me with any questiosn regarding the mod. It took me like 15 mins.

jmoore · Post by **jmoore** » Fri Jul 27, 2007 3:26 pm

gearboy wrote:Awesome! Those guys are really nice. I've met Rich a few times.

I was actually suggesting selling the other 16 on eBay. But sounds like this is going to work out well for you. PM me with any questiosn regarding the mod. It took me like 15 mins.

Yeah, I've always heard great things about Presonus' customer service. I have not been disappointed in the least. I found out from Chad that the mp20 was just discontinued a couple of months ago. He said they had some remaining parts lying around, so he is sending me a new faceplate, 8 replacement knobs and 2 replacement gain pots for less than $40. Seemed very reasonable. I only paid $100 for the preamps.

I took the cover of my mp20 to take a peek at the existing op-amps and it looked like replacing them would be a breeze.

YouTube · Post by **James Steele** » Fri Jul 27, 2007 4:53 pm

I should say that 3 months later, I did finally get my free remote for my Central Station. Hooray.

jmoore · Post by **jmoore** » Fri Jul 27, 2007 6:07 pm

James Steele wrote:I should say that 3 months later, I did finally get my free remote for my Central Station. Hooray.

What can I say...YMMV

nick danger · Post by **nick danger** » Sat Jul 28, 2007 10:32 am

I've got a Presonus Blue Tube stereo preamp I bought with the intention of having the Black Lion mod done to it. Of course, immediately after buying it, they discontinued that mod.

Anybody know of any mods I could do, or have done, to this unit?