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Post by kilroyrock on Jun 13, 2016 11:18:08 GMT -6
In perusing tape op for articles I came across the Jim Williams "Behind the gear" article. This led me to the audio upgrades website for his company, and in his products he has a "pip" chip that you can put in place of an IC 8 pin chip. It says it is good for replacing THAT corp's 1510, which looking at the 1510, I see the 1512 is in the same vein.
I took that idea and remembered the www.diyrecordingequipment.com preamp is based off of the THAT1512. it's only 150 bucks to build for a 500 series preamp.
My question involves whether anyone has ever tried these chips in place of a modern IC and not just replacing the THAT1510 or other in a Toft/Amek console?
I want to build one of those colour pre's, and 50 bucks for a discrete pre amp chip doesn't sound out of the ballpark for a $200 total investment.
Is the Jim Williams pip more of a "you can't find the old stuff, so here's something that will work"? Or is this something that will turn a THAT 1512 circuit preamp to being an even better preamp? I'd be expecting basically the world's cleanest pre ever, which definitely has its place.
I'm hoping I can warrant a response from the grandmaster himself if I'm lucky. Thanks for any and all insight!
links:
pip: audioupgrades.com/products/products_pip.htm preamp: www.diyrecordingequipment.com/collections/colour/products/cp5-mic-preamp-with-colour article: tapeop.com/interviews/btg/90/jim-williams/
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Post by jdc on Jun 13, 2016 12:42:35 GMT -6
i was also looking at this preamp as something to balance all of the wonderful CAPI color i have. would be very interested to hear jimwilliams take.
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Post by kilroyrock on Jun 13, 2016 13:17:20 GMT -6
my big concern was fitting the chip, as pin one would put most of the chip over the capacitor next door, but there are always ways around that kinda stuff..
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Post by jimwilliams on Jun 13, 2016 13:35:49 GMT -6
The PIP is a linear circuit using a high end AD opamp and very low noise Toshiba transistors. It is a direct replacement for the SSM2017, SSM2019, Burrbrown INA217 and That Corp 1510 mic preamp chips. Mounted on a small 7/8" square pcb, it fits most layouts, sometimes you will need to relocate a part.
It has extremely low noise, about -133 db at 50 ohms EIN. Distortion is also extremely low, 1.5 ppm IMD. Slew rate is 60v/us and output current is 50 ma. Power consumption is 12 ma.
This is not a color device, I leave those to others to pursue. This is the truth, if that's in your wheelhouse. There are no mic preamps that can approach its resolution or quality for anywhere its price of $50.
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Post by kilroyrock on Jun 13, 2016 13:52:01 GMT -6
The PIP is a linear circuit using a high end AD opamp and very low noise Toshiba transistors. It is a direct replacement for the SSM2017, SSM2019, Burrbrown INA217 and That Corp 1510 mic preamp chips. Mounted on a small 7/8" square pcb, it fits most layouts, sometimes you will need to relocate a part. It has extremely low noise, about -133 db at 50 ohms EIN. Distortion is also extremely low, 1.5 ppm IMD. Slew rate is 60v/us and output current is 50 ma. Power consumption is 12 ma. This is not a color device, I leave those to others to pursue. This is the truth, if that's in your wheelhouse. There are no mic preamps that can approach its resolution or quality for anywhere its price of $50.
That's exactly what I was hoping for, REAL clean. Thanks for chiming in!
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Post by jimwilliams on Jun 13, 2016 14:42:36 GMT -6
It may be cleaner than measurable. My Audio Precision analyzer does .005% THD+noise and .00015% CCIF IMD. Those are the analyzer residuals. The PIP pretty much double traces those residuals so I really can't say how clean it really is. FFT's are also clean up to -140 dbu. Can't hear that stuff that low.
I can measure the limits of every other preamp I've ever had in the shop, exception is the Audio Upgrades High Speed. That one is also beyond the AP's measurement abilities. It's used in classical music venues, rock bands, foley rooms like Paramount Pictures and even the Church of Scientology. I guess it makes their bull sound like the truth?
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Post by wiz on Jun 13, 2016 14:47:15 GMT -6
I did this a couple of years back..
sounds cool...
it was in a preamp I built myself.. based around the INA217 schematic...
I was gonna build my own PCB but found one on eBay that I could alter and used that.
Used a JLM AUDIO power supply, and a hammond case.. and built two channels.
I tried all the chips, that were around at the time, including Jims PIP version 1. (havent tried the version 2, it wasn't out then)
All the chips sounded slightly different, and I had a blast designing and building the thing... ended up really clean sounding preamps.
It was when I was recovering from shoulder surgery and had 8 months to kill.. so.. you could say, it was so easy I did it one handed... 8)
cheers
Wiz
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Post by jdc on Jun 14, 2016 8:39:27 GMT -6
my big concern was fitting the chip, as pin one would put most of the chip over the capacitor next door, but there are always ways around that kinda stuff.. If you end up doing this I'd be very interested to see how you make it work, please keep us posted!
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Post by kilroyrock on Jun 14, 2016 8:42:04 GMT -6
I need to buy the preamp first!
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Post by jdc on Jun 14, 2016 8:47:39 GMT -6
Why aren't you done yet?! >8(
:-)
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Post by Guitar on Jun 14, 2016 12:43:54 GMT -6
I was thinking the SCA T15 would be a perfect candidate for the Audio Upgrades PIP. It's also SCA's most affordable preamp module, and not hard to build.
It's on my list of things to try...too long of a list. But I tried the SCA "Millennia" channel and I didn't like it, I think Jim's card looks more promising for ultra clarity.
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Post by rocinante on Jun 15, 2016 8:55:17 GMT -6
Looks like a perfect chip for a mixer mic/line channel. In all seriousness.
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Post by kilroyrock on Aug 12, 2016 7:14:21 GMT -6
So I got the chip on, first trading the capacitor underneath for an axial but the axial was just huge, so I re inserted the original cap. Per Jim's suggestion, I stacked sockets until it would fit. Of course the chip is just about now too high, even with the front cover. Works though!
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Post by kilroyrock on Aug 12, 2016 7:15:55 GMT -6
Profile of the chip height Attachments:
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ericn
Temp
Balance Engineer
Posts: 14,953
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Post by ericn on Aug 12, 2016 7:26:58 GMT -6
I did this a couple of years back.. sounds cool... it was in a preamp I built myself.. based around the INA217 schematic... I was gonna build my own PCB but found one on eBay that I could alter and used that. Used a JLM AUDIO power supply, and a hammond case.. and built two channels. I tried all the chips, that were around at the time, including Jims PIP version 1. (havent tried the version 2, it wasn't out then) All the chips sounded slightly different, and I had a blast designing and building the thing... ended up really clean sounding preamps. It was when I was recovering from shoulder surgery and had 8 months to kill.. so.. you could say, it was so easy I did it one handed... 8) cheers Wiz So in other words you were trying to be me !
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DaveC
New Member
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Post by DaveC on Aug 12, 2016 8:30:04 GMT -6
The attached IC socket from Digikey might work better.
Thanks, Dave Attachments:
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Post by kilroyrock on Aug 12, 2016 11:34:28 GMT -6
The attached IC socket from Digikey might work better.
Thanks, Dave I didn't even know that thing existed, pretty cool.
It still wouldn't solve the problem, as the pip is higher than putting the socket on the side, it'd hang off the bottom, similar to being "flush" with the top.
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Post by Johnkenn on Aug 12, 2016 12:19:18 GMT -6
The attached IC socket from Digikey might work better.
Thanks, Dave Dave - how is your Integer pre different from Jim's? Or is that a dumb non-technical guy question?
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DaveC
New Member
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Post by DaveC on Aug 12, 2016 15:43:36 GMT -6
It’s a good question because I think the main design goals are similar (transparency and clean), but the designs technically are different.
I haven’t used Jim’s High Speed preamp and don’t know a lot about it other than what I’ve read. By all accounts I’m sure it’s an excellent mic preamp. Jim’s design has a rather unique approach using current feedback versus the typical voltage feedback amplifier, which I believe is how it achieves the much faster than typical (at least for audio) slew rate. Jim’s preamp has 60dB gain and a high current cross coupled output stage.
Since the Integer preamp is designed for ribbon mics, phantom power circuitry is removed (including the DC blocking capacitors). It has higher gain and implements a simpler output stage (less current but I opted for fewer components in the signal path).
Thanks, Dave
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Post by wiz on Aug 12, 2016 15:49:27 GMT -6
I did this a couple of years back.. sounds cool... it was in a preamp I built myself.. based around the INA217 schematic... I was gonna build my own PCB but found one on eBay that I could alter and used that. Used a JLM AUDIO power supply, and a hammond case.. and built two channels. I tried all the chips, that were around at the time, including Jims PIP version 1. (havent tried the version 2, it wasn't out then) All the chips sounded slightly different, and I had a blast designing and building the thing... ended up really clean sounding preamps. It was when I was recovering from shoulder surgery and had 8 months to kill.. so.. you could say, it was so easy I did it one handed... 8) cheers Wiz So in other words you were trying to be me ! 8)
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Post by wiz on Aug 12, 2016 15:51:45 GMT -6
can you solder 8 wires to the female part of two sockets, one on each end.
Then instal one socket into the PCB and move the other, and put it somewhere else on the board?
cheers
Wiz
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Post by jrasia on Aug 12, 2016 17:49:21 GMT -6
Makes me wonder if having all those adapters stacked like that would affect inductance or if it's oscillating for that matter.
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Deleted
Deleted Member
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Post by Deleted on Aug 12, 2016 18:21:43 GMT -6
Profile of the chip height Hm, i wonder if it is possible to gear the radial capacitors *somehow* sideways without causing trouble in the pip, carefully constructing something similar to the IC socket that Dave linked to, only for the radials. Using snipped legs of parts soldered on, in a usable ankle. Did this on other occasions to fit too big radials into crowded / too low profile cases, where i had none of the suitable low profile variants at hand. But i never did that in something like such a high-speed pip. There might be a good chance to cause trouble somehow...hm...worth a try?
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Post by kilroyrock on Aug 12, 2016 18:27:24 GMT -6
Makes me wonder if having all those adapters stacked like that would affect inductance or if it's oscillating for that matter. jimwilliams suggested it, actually
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Post by kilroyrock on Aug 12, 2016 18:30:35 GMT -6
Profile of the chip height Hm, i wonder if it is possible to gear the radial capacitors *somehow* sideways without causing trouble in the pip, carefully constructing something similar to the IC socket that Dave linked to, only for the radials. Using snipped legs of parts soldered on, in a usable ankle. Did this on other occasions to fit too big radials into crowded / too low profile cases, where i had none of the suitable low profile variants at hand. But i never did that in something like such a high-speed pip. There might be a good chance to cause trouble somehow...hm...worth a try? I first replaced it with an axial, and used shrink tubing to insulate the leads, but it was so big I still couldn't fit it on the board. I think it looks silly too, but it works. I have to get another radial cap where I didn't cut the extra wire off already and I could lean it out to take out a few sockets. I will admit though that it's got a pretty snug fit.
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