MountCyanide

918 Mic Pre for 500 Series
« on: July 04, 2018, 10:56:50 PM »
Hi. I got a hold of some vintage 918 Opamps (Pacific Recorders) from eBay.
I drew up the circuit from the original Jensen app notes, added the necessary input circuitry - phantom, pad, polarity and a FET DI.
Transformer footprints are for Lundahl (LL1570 in, LL1517 out) and Jensen (JT-16PCjr in, vintage JT-123s that are on eBay in droves and the modern JT-11E out).  Also, it can accept the modern gar918 from CAPI and BLU-18 from DIYRE. Grayhill 71 series or 10kc Alpha ( I really recommend the switch). Everything works and I really dig the tone.  Anyways I had a bunch of PCB's made and have spares. Blue solder mask and gold fingers.
$10 each + shipping. Open to trade offers too.
« Last Edit: July 05, 2018, 08:03:21 AM by MountCyanide »


MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #1 on: July 06, 2018, 06:29:30 AM »
I've got  a different version of this (for modern 918 and 990 only) with transformer DI, relay auto-switching and illuminated switches as well as some 500 series EQ projects too. Inquire within. If there's a decent response I'll take out a white market ad.

rackmonkey

Re: 918 Mic Pre for 500 Series
« Reply #2 on: July 06, 2018, 05:24:53 PM »
PM sent
Whether you think you can or you think you can't, you're probably right.

TillM

Re: 918 Mic Pre for 500 Series
« Reply #3 on: July 16, 2018, 07:35:42 AM »
Wow that was fast.
Cyrus the PCBs looks fantastic.
Shipped on Monday and on Friday they was here in Germany.
Thanks for that ! Really looking forward for the build.
Cyrus is always helpful via email and his documents looks fantastic.
Best regards
Till

MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #4 on: July 16, 2018, 08:12:55 PM »
Danke Till for the nice words and easy transaction.
Enjoy!

pvision

Re: 918 Mic Pre for 500 Series
« Reply #5 on: July 17, 2018, 05:58:51 PM »
Blue Solder Mask and Goldfingers - two Bond villains for the price of one!

Nick Froome

rackmonkey

Re: 918 Mic Pre for 500 Series
« Reply #6 on: July 18, 2018, 01:14:50 PM »
Got the boards, Cyrus. They do indeed look great. Nice work on the optional component support!

Put me down for 2 more of the lighted button/transformer DI boards. Probably more a little later.

Thanks again!

BT
Whether you think you can or you think you can't, you're probably right.

TillM

Re: 918 Mic Pre for 500 Series
« Reply #7 on: August 01, 2018, 01:22:06 PM »
Hi Cyrus,
thank you vor this great pre.
It was a easy build !
Love the color of the pre.
I can confirm that all Lundahl transformer works flawless.

MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #8 on: August 02, 2018, 12:37:15 PM »
Excellent! Glad you dig it and thanks for the follow up.

iturnknobs

Re: 918 Mic Pre for 500 Series
« Reply #9 on: August 02, 2018, 07:17:44 PM »
PM sent for purchase


MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #10 on: August 03, 2018, 03:05:45 PM »
Gotcha  ;)

Re: 918 Mic Pre for 500 Series
« Reply #11 on: August 04, 2018, 02:13:01 AM »
interested in a pcb, how do i get one? Thanks

Re: 918 Mic Pre for 500 Series
« Reply #12 on: August 04, 2018, 03:04:02 PM »
PM sent!

MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #13 on: August 05, 2018, 05:03:00 PM »
Got you guys. I've sold out of the modern illuminated preamp board. Thank you all!
TillM had some great feedback and I've incorporated his thoughts into a new revision of the illuminated PCB. Full Lundahl, Jensen AND Cinemag compatibility for all 3 transformer positions will now be in effect. Optional load isolator has also been added (as per Deane Jensen's notes). So this new version (v4.1) will be the one to get.

Putting in an order for a fresh batch and they'll be available in about two weeks.
I still have a bunch of the vintage style version.

Meanwhile I'm making a request to move over to the White Market as this is no longer just merely selling personal overstock. Full or partial kits may happen too if you guys want it. 500 series graphic and 4 band inductor equalizers will be up there shortly as well.
Thanks so much for your support and interest!

Cyrus

MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #14 on: August 20, 2018, 06:12:33 AM »
Hello all-
Just updating here.
Awaiting shipment of the new PCB's - should be in the next day or two - then we'll be ready to rock!

rackmonkey

Re: 918 Mic Pre for 500 Series
« Reply #15 on: August 20, 2018, 01:18:08 PM »
Thanks for the update, Cyrus!
Whether you think you can or you think you can't, you're probably right.

MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #16 on: August 24, 2018, 04:35:21 AM »
New PCB's are in!
Tested, working well and sounding excellent.
Added the Cinemag CMMI-2C footprint and the Pikatron DI transformer is now fully compatible.
If you've ordered and paid, I'm sending them out tomorrow.
If you haven't yet, get some before I get solder crazy and build them all  ;D

Here's how we're looking--- (I bypassed the output fader. There's jumper accommodations for that. I also didn't populate the Jensen recommended load isolator )
https://www.dropbox.com/s/90dpjdyr7mw3wdl/Populated%20818%20v4_1_sm.jpg?dl=0
« Last Edit: August 24, 2018, 04:43:11 AM by MountCyanide »

MountCyanide

Re: 918 Mic Pre for 500 Series
« Reply #17 on: September 13, 2018, 08:48:37 PM »


 

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