Search found 9 matches

by JP.
Wed Mar 03, 2021 9:50 am
Forum: Build
Topic: Phono Transfer System Construction Information
Replies: 251
Views: 6641771

Re: Phono Transfer System Construction Information

mediatechnology wrote: Wed Mar 03, 2021 9:34 am JP.: The test record is the only difference?

I did notice the left and right y-axis scale differences.
Yes. TRS-1007 vs. TRS-1005.
by JP.
Wed Mar 03, 2021 9:19 am
Forum: Build
Topic: Phono Transfer System Construction Information
Replies: 251
Views: 6641771

Re: Phono Transfer System Construction Information

JP. Is that last image a 150 pF or 0 pF load? The header reads 150 but the .wav file has 0 pF in the path. I'm guessing 0. The distortion peak is bodacious. Similar to what I heard with the '681 lightly loaded. 150pF. The file nomenclature I used at the time was additional capacitance added. In cas...
by JP.
Tue Mar 02, 2021 9:55 pm
Forum: Build
Topic: Phono Transfer System Construction Information
Replies: 251
Views: 6641771

Re: Phono Transfer System Construction Information

150pF is ideal for the 150MLX according to what I believe is a fairly accurate test record.
46538C8D-AD70-40F4-A547-63A330A40CB5.jpeg
by JP.
Sun Dec 08, 2019 8:43 pm
Forum: Build
Topic: Flat Balanced Input Moving Coil Phono Preamp Construction Information
Replies: 56
Views: 247307

Re: Flat Balanced Input Moving Coil Phono Preamp Construction Information

Maybe, maybe not. After grounding the case I removed the tab to take a ‘before’ measurement. The interference wasn’t there anymore. I’ll need to experiment more with it later.
by JP.
Sat Dec 07, 2019 10:50 am
Forum: Build
Topic: Flat Balanced Input Moving Coil Phono Preamp Construction Information
Replies: 56
Views: 247307

Re: Flat Balanced Input Moving Coil Phono Preamp Construction Information

In practice the MM setup has more noise. Not in practicality, but at full volume 60Hz and harmonics dominate from the cartridge. Not so with the MC setup. This is solved. The headshell on the EPA-501H is composite, and the AT-150MLX lower body is not electrically connected to the upper. I used the ...
by JP.
Fri Dec 06, 2019 5:01 pm
Forum: Build
Topic: Flat Balanced Input Moving Coil Phono Preamp Construction Information
Replies: 56
Views: 247307

Re: Flat Balanced Input Moving Coil Phono Preamp Construction Information

In practice the MM setup has more noise. Not in practicality, but at full volume 60Hz and harmonics dominate from the cartridge. Not so with the MC setup. One recommendation - put the 4K99 resistors in the BOM. I hadn't read the build guide in-depth so I didn't know to order them. Luckily I've a goo...
by JP.
Fri Dec 06, 2019 4:30 pm
Forum: Build
Topic: Flat Balanced Input Moving Coil Phono Preamp Construction Information
Replies: 56
Views: 247307

Re: Flat Balanced Input Moving Coil Phono Preamp Construction Information

This chassis: https://proaudiodesignforum.com/forum/php/viewtopic.php?f=7&t=753&start=30#p9224. I bought 4 when I did the flat MM build. Glad I did too as I see that size isn't available from them anymore. As I was in a hurry to get the build done before I left the house for the week I swapp...
by JP.
Fri Dec 06, 2019 2:22 pm
Forum: Build
Topic: Flat Balanced Input Moving Coil Phono Preamp Construction Information
Replies: 56
Views: 247307

Re: Flat Balanced Input Moving Coil Phono Preamp Construction Information

Hey Wayne, I've been looking forward to this release for some time. Finished putting together one of my units last weekend. I used one of the MM boards to balance the signal from my generator with a 1:100 pad at the output to get .775 VRMS to the two 4K99 series resistor at the input of the MC board...