Page 1 of 1

Seeburg LS1 - adding an aux input

Posted: Sun Sep 07, 2014 4:37 pm
by cdubya
Hi,

I am new to this forum and I recently purchased a working Seeburg LS1. I want to add a input to the amplifier on the jukebox so that I can play audio from a ipod/android/phone/computer ( minijack ) . I searched through the posts to see if this question had already been asked but didn't find anything. Any help would be appreciated.

Colin

Re: Seeburg LS1 - adding an aux input

Posted: Sun Sep 07, 2014 5:01 pm
by Ron Rich
Hi Colin,
You can do this at the volume control. If you look at the frame holding it, there is a "knock-out" for a three wire socket, just for that purpose. Ron Rich

Re: Seeburg LS1 - adding an aux input

Posted: Sun Sep 07, 2014 5:50 pm
by cdubya
Hi Rich,

Thanks for your reply. I have the installation and operation manual and there is no mention of the knock-out. Also where would I connect the minijack line to amplifier ? Here are a couple of snaps of the back near the volume knob and the amplifier

Image

Image

Colin

Re: Seeburg LS1 - adding an aux input

Posted: Sun Sep 07, 2014 8:41 pm
by Ron Rich
Hi Colin,
You are looking at the volume control thru the rear access panel--you need to remove the amp from the phonograph to see the knock-out, on the frame-
Electrically, if you want the control to control volume of you added device, you connect to the "low sides". If you want to use another control, connect to the "high sides". See the service manual schematic--use a relay controlled via the SCC "audio control switch".
Also--read your "I & O Manual", for proper speaker hook up !
Ron Rich

Re: Seeburg LS1 - adding an aux input

Posted: Mon Sep 08, 2014 9:24 am
by MattTech
As many people ask about "adding" auxillary" input to vintage devices - (CD, MP3, etc) it's important to note that the "line level" be adhered to, within reason.
This simply means that roughly a half-volt input be produced at said terninals, and also consideration of the impedendce be adhered to, to avoid frequency "squashing"" of the input device.

Yes, this sounds technical, but a thorough undestanding of electronics shows that this is required in such cases.
Just shoving "in" of a device can usually result in less-than-satisfactory results.

Re: Seeburg LS1 - adding an aux input

Posted: Mon Sep 08, 2014 2:49 pm
by Rob-NYC
Ron Rich wrote:Hi Colin,
You can do this at the volume control. If you look at the frame holding it, there is a "knock-out" for a three wire socket, just for that purpose. Ron Rich


The problem here is the mute relay. It clamps the high side of the volume control in all modes except play. If AUX input to the amp is really desired I'd install a 120vac relay who contacts would open the mute relay coil circuit when the mech motor is at rest.

Input to the V.C will be 25K-ohms -a bit low for CD players but should be fine for MP3 players and most computers as they are designed to work into headphones. Level at that point is spec'ed at 0.075 -a bit low for line sources, but since it goes directly into the control it shouldn't be a problem. I don't know if the circuits preceding the control will have any loading or frequency response effect.

Rob

Re: Seeburg LS1 - adding an aux input

Posted: Mon Sep 08, 2014 4:35 pm
by Ron Rich
Rob,
It's been years since I have added any inputs to an amp, but in my humble mind, it seems that the low side was "clamped"--not the high side --No schematic here today ?? Ron Rich

Re: Seeburg LS1 - adding an aux input

Posted: Tue Sep 09, 2014 4:34 am
by Rob-NYC
Ron Rich wrote:Rob,
It's been years since I have added any inputs to an amp, but in my humble mind, it seems that the low side was "clamped"--not the high side --No schematic here today ?? Ron Rich


The closest I have is an schematic for a TSA-7 -too lazy to scan it. Here is a 5 from Vern Tisdale: http://www.verntisdale.com/schem/tsa5.jpg Same architecture. From my experience Seeburg and all the others always mute before the volume control.

Was there ever a kit for an aux or mic input?

Rob

Re: Seeburg LS1 - adding an aux input

Posted: Tue Sep 09, 2014 4:48 am
by Ron Rich
Rob,
There were several "kits"--I never installed one on anything older then a TSA10B --which was"plug in", from then on--
Ron Rich