The Secret Society of Lathe Trolls

Thanks for sending the samples James.
They sound really good.

I noticed during the tones that the L>R cross talk was in-polarity and the R>L out-of-polarity.
Trying to wrap my head around that.

Thank you very much for that. So it's not completely universal because we have the Ortofon cutterhead whose recording crosstalk can be in either polarity depending on mechanical adjustment. I had wondered if there were pivoting systems... My reasoning that Left vertical movement in the 45 degree pla...

Vinyl Polarity Relationships in the Westrex 45/45 System This discussion ties together several loose ends regarding mechanical, electrical, absolute and crosstalk polarity in the Westrex 45/45 system. It is not a discussion on the audibility of absolute acoustic polarity. The motivation for this in...

I updated the drawing to show two links for "A." If the cartridge body floats from the headshell (and apparently most do) then link A2, the cart ground strap, can remain. You can usually pick up a little S/N in that channel by removing link A2. If link A1 and A2 are fitted that channel becomes unbal...

I'm starting to get questions about how to wire tonearms fully-balanced for use with the Flat Phono Preamp. A picture is worth a thousand words. http://www.waynekirkwood.com/images/jpg/Balanced_Arm_Wiring_small.jpg Balanced Tone Arm Wiring Diagram for the Flat Phono Preamplifier. Ground strap "A" s...

I had a the need to build a Flat Balanced Input phono preamp with XLR inputs and outputs for a vinyl streaming application and wanted to share the pics. http://www.ka-electronics.com/images/jpg/Flat_Preamp_VS_Build_Top.jpg Flat Balanced Input Balanced Output Moving Magnet Phono Preamplifier with XL...

Hi trolls - I wanted to let people know that I now have PC boards for the Phono Transfer System in stock which include both the flat preamp and the RIAA EQ/Monitor Switcher board. I don't have the web page built for them on the http://www.ka-electronics.com site but the ebay listings for them may be...

Hi trolls - I wanted to let people know that I now have PC boards for the Phono Transfer System in stock which include both the flat preamp and the RIAA EQ/Monitor Switcher board. I don't have the web page built for them on the http://www.ka-electronics.com site but the ebay listings for them may be...

Hi trolls - I wanted to let people know that I now have PC boards for the Phono Transfer System in stock which include both the flat preamp and the RIAA EQ/Monitor Switcher board. I don't have the web page built for them on the http://www.ka-electronics.com site but the ebay listings for them may be...

I wanted to provide an update on the project now that I've had a chance to make a box for it. The Flat Phono Preamp PC board fits nicely in a Hammond 1590BBBK enclosure. Paul suggested using 9 Pin D connectors to minimize panel space and it worked out nicely. I won't need remote gain switching so 9 ...

Thanks Bryan.

I did a small pre-production run of four and have two sets of preamp and EQ boards available.
Will be sending you a PM.

I have a small run of pre-production RIAA/Inverse RIAA EQ Monitor Switcher boards now and wanted to update the Inverse RIAA thread. The jumpers look like this: http://www.waynekirkwood.com/images/jpg/EQMONSW_RIAA_Inverse_RIAA_Jumpers.jpg RIAA EQ/Inverse RIAA EQ jumpers The EQ circuit on the left has...

Got the pre-production run of boards in for the RIAA EQ/Monitor Switcher and they checkout OK. The board is a Swiss Army Knife capable of also doing line-level Inverse RIAA. http://www.ka-electronics.com/images/jpg/EQMONSW_33_PC_Board_800.jpg RIAA EQ/Flat Dual Path Monitor Switcher for the Flat/RAW...

I did a drawing of the proposed front panel to help visualize the switching and routing options. http://www.waynekirkwood.com/images/jpg/Flat_Phono_Preamp_Front_Panel_Switches.jpg RIAA EQ and Monitor Switcher Front Panel Switches for the Flat Phono Preamp The switches from left to right operate RY1,...

Interesting thread. I have a hard time listening to music from a stationary position unless I'm in a car. At home I tend to be an active listener pinned down in the sweet spot only when I'm trying to listen to something critically. I'm usually listening to music doing something else. Sitting down fo...

This is part two of the Flat Phono Preamp for RAW Transfers series that describes the RIAA EQ/Monitor Switcher "mult-tasker." Part 1, the Flat Balanced Input/Balanced Output MM preamp, is here: http://www.lathetrolls.com/viewtopic.php?f=9&t=5914 Background from the previous thread: For a number of ...

Hi Trolls. For a number of years I've been working on a moving magnet preamp for flat, "no RIAA EQ applied" RAW recording. Flat recording gives de-clicking software a far better capture to work with. Once de-clicked, the files can be rendered with RIAA in DSP. One of the most obvious limitations do...

Thanks everyone for your replies. I expect to post the balanced input flat preamp schematic here soon and then follow up with the EQ/Monitor switcher. It's interesting that the same albums tubeactive mention are ones that I use for listening tests. Santana Abraxis, Blood Sweat and Tears, and Hot Tun...

I've been working on a fully-balanced input moving magnet cartridge preamp. I'll post details about it soon. One of the issues I ran into during development were the limitations of coaxial cable and RCA plugs. A fully-balanced input benefits from fully-balanced wiring. Though most tonearms seem to ...

Thanks everyone for the views and comments. I wanted to provide some follow-up information. As a reality check I decided to check the Inverse RIAA feeding the RIAA playback EQ end-to-end. I first checked the playback RIAA EQ network accuracy using the Jung/Lipshitz network through the preamp low-lev...