Topic: Lunatec V3 ADC Upgrade

[blee421]

I recently sent in my two Lunatec V3 units to have the ADC's upgraded. The cost was $100 per unit. I sent in the two V2's I own earlier and after they were tuned up I asked if there were any upgrades that Grace does for the V3's that are similar to what Oade Bros was doing. I think they call it a "concert mod". I might be wrong about this but their website says $175 for the upgrade. Anyways I asked Alex Vallejo with Grace to send me specifics on what's being done so that I could share it with all of you fine people.

Hey Brian,

I replaced the AD712s used in the trim/HPF buffer and ADC input buffer with OPA1652 as per Mike's recommendation. I just compared stock unit to modified and distortion + noise is negligible, ~1dB improvement. ADC Dynamic range is 2-3dB better. Is the mod worth it? Guess you'll have to try it out...

 

[Gutbucket]

Thanks.  My understanding was that the Ode mod replaced the ADC chip, but maybe it replaced those same buffers.  Anyone know the specifics?

[steve4134]

Well shit..........you want to buy another V3 let me know. Coax / optical mod.

Steve

[jb63]

If it helps, the OADE ACM mod affects the digital out only leaving the analog out unchanged. Whenever I have an extra channel I run both outs so I have a lot of examples if you need any.

http://taperssection.com/index.php?topic=79244.0;all

I haven't found a mod of anything I like as much as this, but its a giant heavy piece of kit for 2024.

[audBall]

I replaced the AD712s used in the trim/HPF buffer and ADC input buffer with OPA1652 as per Mike's recommendation. I just compared stock unit to modified and distortion + noise is negligible, ~1dB improvement. ADC Dynamic range is 2-3dB better. Is the mod worth it? Guess you'll have to try it out...

Thanks for sharing, Brian.

In my stock version, I see three AD712s and one PCM1804 (a 24bit/192kHz stereo AD converter). According to this link, the AD712 is an op amp. Was the AD chip left unchanged?

Does anyone know which chips get replaced by Doug?

[DSatz]

I didn't see this upgrade mentioned anywhere on gracedesign.com; does anyone have a link to where it's described?

[Gutbucket]

Not a much info on it, but here is a link to the page on it at the Oade Brothers Audio website- https://www.oade.com/index.php?main_page=product_info&cPath=19&products_id=96

[blee421]

Hey just wanted to give some feedback. I recorded Mike Gordon awhile back and all of the low end sounded great. Then recently recorded two nights of Goose and wanted to compare the V3 to V3>AD2K+. One thing to mention is the upgrade done to the V3 is the circuit from the preamps to the digital chip is what’s replaced. Alex Vallejo at Grace walked me through the benefits and it’s about 3-4db of cleaner gain. The analog side stays the same. So the V3 sounded better to me and the AD2K+ was right there with it very similar but I ran it at +16 and someone told me that needed to be 24db setting. The analog side of the V3 is 1db hotter??? That’s what I heard. Been listening to both in the car and they sound great. For Mike Gordon I did a digi recording into a 722 and an analog recording into a MixPre 6 I. That sounded different with the analog being warmer and the digi having lots of detail but just a bit different.

I sent 2 units in and one other guy bought a unit off me. He is a WSP taper mainly and runs 4022’s into it pretty much. I haven’t heard many of his recordings yet and not much feedback from him.

That’s all I got!! I grabbed a SD 552 and I’m running 4ch DPA > SD 552 > 744T (2 digital pairs) is what’s on deck next. Then V2 > MiniMe > 702T. I bought a Soundfield ST250 and that needs dusted off. If I could only get out more!! I might drive down the street and record the ocean here soon.

[todd e]

an st250, hell yes!  lemme borrow it one day, i'd love to run it too

[blee421]

an st250, hell yes!  lemme borrow it one day, i'd love to run it too

Yeah this mic is really what its all about. Its a great way to learn about why microphones do what they do.

[kindms]

Hey just wanted to give some feedback. I recorded Mike Gordon awhile back and all of the low end sounded great. Then recently recorded two nights of Goose and wanted to compare the V3 to V3>AD2K+. One thing to mention is the upgrade done to the V3 is the circuit from the preamps to the digital chip is what’s replaced. Alex Vallejo at Grace walked me through the benefits and it’s about 3-4db of cleaner gain. The analog side stays the same. So the V3 sounded better to me and the AD2K+ was right there with it very similar but I ran it at +16 and someone told me that needed to be 24db setting. The analog side of the V3 is 1db hotter??? That’s what I heard. Been listening to both in the car and they sound great. For Mike Gordon I did a digi recording into a 722 and an analog recording into a MixPre 6 I. That sounded different with the analog being warmer and the digi having lots of detail but just a bit different.

I sent 2 units in and one other guy bought a unit off me. He is a WSP taper mainly and runs 4022’s into it pretty much. I haven’t heard many of his recordings yet and not much feedback from him.

That’s all I got!! I grabbed a SD 552 and I’m running 4ch DPA > SD 552 > 744T (2 digital pairs) is what’s on deck next. Then V2 > MiniMe > 702T. I bought a Soundfield ST250 and that needs dusted off. If I could only get out more!! I might drive down the street and record the ocean here soon.

did you buy Chase's st250 ? out of curiosity

[DSatz]

Aha: On reading more carefully, I see that this isn't a Grace mod -- it's an Oade mod. Things make more sense now; thanks.

[blee421]

Aha: On reading more carefully, I see that this isn't a Grace mod -- it's an Oade mod. Things make more sense now; thanks.

Its a Grace Mod. Alex Vallejo at Grace did the work on it.

Yes I bought Chase's soundfield. He is happy with his shotguns.

[kindms]

Aha: On reading more carefully, I see that this isn't a Grace mod -- it's an Oade mod. Things make more sense now; thanks.

Its a Grace Mod. Alex Vallejo at Grace did the work on it.

Yes I bought Chase's soundfield. He is happy with his shotguns.

I only asked because as soon as i walked in to night 1 of phish in albany he was asking to buy one of my stereo mics LOL

[DSatz]

I wrote to Grace Audio asking about this upgrade, and received this reply from Alex Vallejo:

> There is a relatively minor upgrade we can do to the V3. We replace the AD172s with OPA1652s in the trim, HPF and ADC buffers. Measures about 1dB lower noise, 2-3dB ADC dynamic range. Didn't really make an audible difference for me, but we can do it for $100 + shipping if you want it. I would need the unit serial #, shipping address and phone # to issue an RMA.

Two of those circuit areas (the "trim" and "HPF") are at places in the analog path where any improvement in performance should affect both the analog and digital outputs.

I will probably have this done even though I haven't done much live recording since the pandemic started.

[F.O.Bean]

Aha: On reading more carefully, I see that this isn't a Grace mod -- it's an Oade mod. Things make more sense now; thanks.

Its a Grace Mod. Alex Vallejo at Grace did the work on it.

Yes I bought Chase's soundfield. He is happy with his shotguns.

sweet score. I'd love to give ambisonics a try someday, but i'd prob NEVER be happy with just one source Schoeps ambisonic mic and I'd be in heaven (not that I could afford it right away anyway) LOL. Anyone have comps of the ST-250 vs Sennheiser ambeo?

I JUST listened to Jef Fugh's (old Team Pittsburgh taper) of his stage-lip ST-250/V3/Sony Laptop @ 24Bit Charlie Hunter Trio from 5/21/2007 earlier today, so strange coincidence to see this thread. I've JUST transferred my 481/V3/JB3 source and I'm going to comp it to Jef's source later tonight. But I'm not sure what config he ran? Maybe Blumlein? Man, I miss my old Busman BSCS-L stereo mic I had back in 2011/2012. Schoeps + that was titties 88:

[Gutbucket]

I JUST listened to Jef Fugh's (old Team Pittsburgh taper) of his stage-lip ST-250/V3/Sony Laptop @ 24Bit Charlie Hunter Trio from 5/21/2007 earlier today, so strange coincidence to see this thread. I've JUST transferred my 481/V3/JB3 source and I'm going to comp it to Jef's source later tonight. But I'm not sure what config he ran? Maybe Blumlein? Man, I miss my old Busman BSCS-L stereo mic I had back in 2011/2012. Schoeps + that was titties 88:

OT, but this brought to mind the first time I recorded using the TetraMic, stage lip for Charlie Hunter Trio back in 2010 or so.  Ironically I don't think I ever even listened to that as I also ran four omnis across the front of the stage and just used that in the mixdown I did for a guy running video, then got distracted with other stuff, even though my original intent was to comp the two recordings. ..and similarly I ran the TetraMic on that outing in place of the Peluso P-Stereo mic, akin to the BSCS-L, which I'd previously been using a lot at stagelip. Ought to dig that one out. /OT

[capnhook]

Man, I miss my old Busman BSCS-L stereo mic I had back in 2011/2012. Schoeps + that was titties 88:

It's doing just fine Bean, here on the stage in my hometown..bottom right of frame

https://youtu.be/qxiPg0faL4k?t=1520