THATDIP Preamp - THAT1570/5171 Digitally Controlled Mic Pre [PICS]

[Nadege]

Awsome project ! I'll be in if available .

Keep us updated !

;D

 

[samsagaz]

no news?

 

[promixe]

Ok, so there is some interest! =) I put the project on hold for a while but I think it is now time to resume. =)

I am starting to work on finishing up the production version of the firmware, as well as a PSU and a MIDI board for starters. What I already have:

- Finished and tested THATDIP LucidityPreamp PCBs (that accomodates THATDIP adapters)
- Finished and tested THATDIP adapters for THAT1570/5171 chipset
- Finished and tested controller front panel (Universal Mic Preamp Controller - UMPC for short) with 3 buttons (48V, POLARITY, PAD)
- The actual controller chip is in beta firmware stage - finishing that up...

The UMPC controller will support THAT only mode for now (because there is a THAT based preamp PCB already finished). PGA support will come depending on demand, as I only have the PGA2500 adapters now, and no actual preamp boards yet. So, if someone needs PGA2500 badly, please voice your request. =)

I will provide basic documentation to get people started but would gladly accept any assistance in this matter. Thanks!

PS: To make you ponder things for a bit here is a blind shoot out of THATDIP Lucidity Preamp vs. Grace Design 201 and Millenia STT-1 (two of the highly regarded preamps in the industry). I will be curious to know which one you think is which. =) The signal path is Neumann U149 -> passive splitter -> PREAMP level matched -> Lynx Aurora 16 A/D -> Pro Tools HD8.

 

[promixe]

A quick update:

- The PSU board is done.
- The new UMPC front panel controller board is done also (features 4 buttons, channel grouping, separate configuration mode jumper, remote ID selection).
- The MIDI board is done. Can be used for other MIDI controlled projects, not just UMPC.

I will place an order with the PCB company as soon as I have enough $$. While I'm waiting on the PCBs, I'll work on the UMPC firmware to get to a solid beta.

 

[mrcase]

Great!
I´d be interested in 4-8 boards!!
I like the vocal1_2 track best, followed by 3 and 1...
can`t which is which since I´ve never heard either.
Congrats to this great project!!!

 

[Meathands]

I will provide basic documentation to get people started but would gladly accept any assistance in this matter. Thanks!

I will be glad to help with documentation when the time comes, shoot me an email.

 

[promixe]

UPDATE:

- PCBs ordered! (finally, now that the Chinese festival is over) =)
- Working on the firmware to finish new beta before the PCBs arrive. Will have grouping and remote channel ID selection through front panel interface (for Avid PRE emulation).

The new preamp PCB has optimized split grounds with an option to stitch 'em at the PSU connector - I'm hoping this will improve EIN somewhat (the current version has -127.5dB - which is already above average pro-audio). =) There is also now an INSERT connector between the preamp and the output stage. Could be used for metering, compressor, ADC, etc...  There are a few other minor improvements.

Stay tuned. Thanks!

 

[HerculesVR]

This is evaluation board, 4-layer layout for best spec performance.

Yeap THAT1570 better than TI/BB PGA2500.

 

[HerculesVR]

UPDATE:

- PCBs ordered! (finally, now that the Chinese festival is over) =)
- Working on the firmware to finish new beta before the PCBs arrive. Will have grouping and remote channel ID selection through front panel interface (for Avid PRE emulation).

The new preamp PCB has optimized split grounds with an option to stitch 'em at the PSU connector - I'm hoping this will improve EIN somewhat (the current version has -127.5dB - which is already above average pro-audio). =) There is also now an INSERT connector between the preamp and the output stage. Could be used for metering, compressor, ADC, etc...  There are a few other minor improvements.

Stay tuned. Thanks!

You should choose good Chinese PCB factory such as chinafastprint, most low cost low quality FR-4 will reduce noise performance when high gain. For example, SYST-1141 is good at  MICPRE.

Do you use NJM2114DD for balanced output stage? it is good colorful sound.

THATDIP adapter is good job. I dun like solder QFN package.

 

[cyrano]

Count me in!

This is EXACTLY what I was looking for. Can't wait  ;D

 

[rmaier]

Me too, please?

Ralph

 

[promixe]

I will have 50 channel PCBs next week, but only 16 THATDIP adapters to start with. I will order and assemble more adapters as soon as this project generates $ (i.e. as soon as the first 16 channels are sold).

I will also have 10 PSU PCBs and 10 Front Panel PCBs (each PCB controls up to 8 preamp channels) to start with.

Thanks!

 

[rmaier]

Great. Please let us know once you've worked out prices.

Ralph

 

[loicm]

Dear Promixe,


I would be glad to help on this project. I just ordered an evaluation board from THAT. I was thinking to do the same project as you ...

Here is a link for the THAT chip : http://www.thatcorp.com/datashts/DigMicPre_Seminar.pdf

and another one for the TI chip : http://www.ti.com/product/pga2500

I'm in if possible for 8 preamp.

Do you plan to put all those 8 preamp on a single board ? It would be great. I can help for this if you use Eagle software for the PCB.

I send you a PM.

Best regards,
Loïc

 

[rytmpoczta]

...
PS: To make you ponder things for a bit here is a blind shoot out of THATDIP preamp vs. Grace Design 201 and Millenia STT-1 (two of the highly regarded preamps in the industry). I will be curious to know which one you think is which. =) The signal path is Neumann U149 -> passive splitter -> PREAMP level matched -> Lynx Aurora 16 A/D -> Pro Tools HD8.

Hello,
So tell us, which one is which in this comparision???

In my opinion:
Vocal 1_1 - Grace Design
Vocal 1_2 - Millenia
Vocal 1_3 - That

 

[go4thaudio]

If there were a generic interface such as VST I feel this project would generate a great deal of interest within the SAWstudio community.  The Appsys RGC remote gain controller has VST software that is controllable from SAW host computer and/or SAW remote applications.  I can send a link if it helps.  Of course this project is much more to my liking.  I too have been looking at THAT for a project like this but am still very novice.  Perhaps this project would be a good reason for me to learn bit banging and/or explore the Steinberg SDK.  Any news yet on price and availability for PCB's?  I would like to pass this info along to SAWstudio usergroup.

 

[promixe]

...
PS: To make you ponder things for a bit here is a blind shoot out of THATDIP Lucidity Preamp vs. Grace Design 201 and Millenia STT-1 (two of the highly regarded preamps in the industry). I will be curious to know which one you think is which. =) The signal path is Neumann U149 -> passive splitter -> PREAMP level matched -> Lynx Aurora 16 A/D -> Pro Tools HD8.

Hello,
So tell us, which one is which in this comparision???

In my opinion:
Vocal 1_1 - Grace Design
Vocal 1_2 - Millenia
Vocal 1_3 - That

Let's not give it out to everyone just yet. =) I'm sending you a PM with what's what.

 

[promixe]

If there were a generic interface such as VST I feel this project would generate a great deal of interest within the SAWstudio community.  The Appsys RGC remote gain controller has VST software that is controllable from SAW host computer and/or SAW remote applications.  I can send a link if it helps.  Of course this project is much more to my liking.  I too have been looking at THAT for a project like this but am still very novice.  Perhaps this project would be a good reason for me to learn bit banging and/or explore the Steinberg SDK.  Any news yet on price and availability for PCB's?  I would like to pass this info along to SAWstudio usergroup.

I've been working on a universal OSC control for the preamps (and a whole lot more of other gear) through AU/VST and standalone apps. No intermediary gear will be required - just plug in your preamp into a router/hub or directly into your PCs ethernet. It's a couple of months away I think, but it's coming. =)

Help with AU/VST programming is welcome.

 

[bremusound]

I'm interested in a 8ch unit, maybe another 1-2 8ch units later... PGA preferred since i have some of those laying around...

 

[promixe]

I'm interested in a 8ch unit, maybe another 1-2 8ch units later... PGA preferred since i have some of those laying around...

I'm going to start sales with THAT1570/5171 based designs. Honestly I've been pondering the PGAs for a while and I don't really see a clear reason to design my own PGA PCBs anymore due to the following reasons:

- Igor has done it already (WIREGAIN preamp)
- THAT chipset does everything PGA does, easier to program for, I personally prefer its topology and sound to PGA. The overload feature on the PGA2500 could be replicated on the THAT chipset as well, which I will implement down the line.

I, however, do offer PGA2500-optimized high-performance DIP-28 adapters (read about it HERE). I have around 80 of them in stock. The main purpose of designing these adapters was DIY-friendliness, i.e. you wouldn't have to solder those SMD packages and would either use the adapters directly in your board designs or prototype with them on a breadboard. I have about 80 PGA adapters unassembled PCBs left if you are interested in using your own chips on them. If you buy over 10 pc. they would be $5/each.

My front panel controller (UMPC) will initially support THAT chipset and a remote control mode (where it acts just as a display+interface, but doesn't actually send control messages to preamps; the remote board does. More on that later...). But it's in my to-do list to finish full support of up to 8 PGA2500s in a daisy-chain configuration. Stay tuned!

PS: The PCB order is going to be here any day now. I'm going to announce pricing after I test everything and am ready to sell. Thank you!