-----Original Message----- From: Jay <jukebox-list@lists.netlojix.com> To: jukebox-list <jukebox-list@lists.netlojix.com> Cc: jay <jay@west.net> Date: Friday, 10 October 2025 1:40 AM CDT Subject: [Jukebox-list] Re: AMI E 80 sound issues with magnetic cartridge upgrade On 10/9/25 19:01, joeymcd via Jukebox-list wrote:

I have a problem with an AMI E80 making a resonating sound while scanning. I just installed an Audio Technica AT3600 magnetic cartridge. Tied the positives together and negetives together at the cartridge. Installed an external preamp as well. Sound and tracking are good. No issues if it scans a couple selections.

Problem is when it is scanning distance it picks up a very loud resonating sound that stops immediately when the needle lands in play position.  Not sure if the mute relay turns on or off in play position but when the needle lands and the click of the relay is heard the loud resonating stops immediately.

Amplifier has been rebuilt DD model previously and sounded decent with the crystal cartridge but wanted to upgrade for lighter tracking and stereo compliance. No loud resonating issue at all.

I have done this with an AMI F model with no issues. I know the F model uses an amplifier that is designed to use a magnetic cartridge but wired the cartridge the same way.

You can't directly substitute a magnetic for a crystal cartridge. The voltages and frequency response are quite different, the magnetic needs a preamplifier and equalizer. If you can find an R-145 amp that was used in the F through J it would work because that's built in to it. Or you could wire in a separate phono preamp. What's puzzling is that the howl is only there when it's supposed to be muted. I don't see a mute relay on the R-111 amplifier schematic for the E series. There's a relay that keeps the turntable from spinning on a cold start until the 6L6s warm up, but I don't see a mute relay. In any case you'll need to solve the incompatibility between a magnetic cartridge and a crystal input. This may fix the howl, especially if there's no muting. HI Jay. I did install an external preamp. I spliced the new cartridge into the existing tone arm cable. Then replaced the original plug on the end of the tone arm cable with an RCA Y plug to male and plug directly into the preamp. The output of the preamp goes into the AMI DD amplifier and then out to the speakers. Joey McDonald

Joe, is this noise a hum? Does the noise only occur when the mech is at certain points of travel? Does it still happen if the lead from the cart to the preamp is unplugged? There may be an intermittent break in the cable shield from the cart. A magnetic cart is --much-- more sensitive to external electromagnetic fields, such as an AC turntable motor. Try moving the preamp box while the noise appears during scan. It is possible the field from the TT motor is getting into the cartridge cable from the mech. Check to make sure the cartridge is "floating" electrically. this means it has no continuity to the mech and only connects to the new preamp input. The mech should have a ground wire to the grounding terminal on the preamp (if present). RobNYC On Friday, October 10, 2025 at 08:55:17 PM GMT-5, joeymcd via Jukebox-list <jukebox-list@lists.netlojix.com> wrote: -----Original Message----- From: Jay <jukebox-list@lists.netlojix.com> To: jukebox-list <jukebox-list@lists.netlojix.com> Cc: jay <jay@west.net> Date: Friday, 10 October 2025 1:40 AM CDT Subject: [Jukebox-list] Re: AMI E 80 sound issues with magnetic cartridge upgrade On 10/9/25 19:01, joeymcd via Jukebox-list wrote:

I have a problem with an AMI E80 making a resonating sound while scanning. I just installed an Audio Technica AT3600 magnetic cartridge. Tied the positives together and negetives together at the cartridge. Installed an external preamp as well. Sound and tracking are good. No issues if it scans a couple selections.     Problem is when it is scanning distance it picks up a very loud resonating sound that stops immediately when the needle lands in play position.  Not sure if the mute relay turns on or off in play position but when the needle lands and the click of the relay is heard the loud resonating stops immediately.   Amplifier has been rebuilt DD model previously and sounded decent with the crystal cartridge but wanted to upgrade for lighter tracking and stereo compliance. No loud resonating issue at all.   I have done this with an AMI F model with no issues. I know the F model uses an amplifier that is designed to use a magnetic cartridge but wired the cartridge the same way.

You can't directly substitute a magnetic for a crystal cartridge. The voltages and frequency response are quite different, the magnetic needs a preamplifier and equalizer. If you can find an R-145 amp that was used in the F through J it would work because that's built in to it. Or you could wire in a separate phono preamp. What's puzzling is that the howl is only there when it's supposed to be muted. I don't see a mute relay on the R-111 amplifier schematic for the E series. There's a relay that keeps the turntable from spinning on a cold start until the 6L6s warm up, but I don't see a mute relay. In any case you'll need to solve the incompatibility between a magnetic cartridge and a crystal input. This may fix the howl, especially if there's no muting. HI Jay. I did install an external preamp. I spliced the new cartridge into the existing tone arm cable. Then replaced the original plug on the end of the tone arm cable with an RCA Y plug to male and plug directly into the preamp. The output of the preamp goes into the AMI DD amplifier and then out to the speakers. Joey McDonald _______________________________________________ Jukebox-list mailing list -- jukebox-list@lists.netlojix.com To unsubscribe send an email to jukebox-list-leave@lists.netlojix.com %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s Searchable Archives: http://jukebox.markmail.org/