modding line in/out to an old Electra Echo unit

IronWine

Member
so i bought this old echo reverb unit by Electra. model EP 250. this specific unit had been rebranded to the spanish market but afaik it is the same unit, made in japan ofcourse. theres bits and pieces of info around but not too much haha

i would date it to early 1980. but im no expert.

anyhow, this thing has mic/instr. ins and switchable outs. i want to add a line level input(s), even as a seperate little box if it's easier. and then work it out with my AUX sends on the mixer and apply it to different channels, so i won't be restricted to use it in the mic chain itself.

not sure about the outputs because it does have a 0db option which to my humble experience relates to line level signal.

pretty simply layout inside..all the interesting stuff is underneath tho so i'd have to take it apart sometime haha

any advices appriciated

cheers


btw i can't seem to rotate this picture..on my pc it's just right..
 

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Silly question - but despite the 'instrument' input and the -20/-30dB labelling, have you actually tired it on your line outs? If your line outs are the usual unbalanced .775V level, then I'd bet that the design will be quite happy taking your send output with the level control on the fx unit kept down low. Back then, things in general were a lot less well specified in terms of level, and input level controls were often just across the input, gradually moving the wiper towards ground - so no active components before the level control - just resistor networks to set the working level. Most gear from that period would take a guitar at higher settings, keyboards at around the middle and a cassette desk line at the lower settings. I suggest you give to a go and see. If the line is just too hot, you could build a pad network into a jack plug that will sort it out, but I suspect you won't need it!
 
Yes, 0dB= 0.775V= Line level (in most cases :rolleyes:) So your output should also be ok. Will not overdrive your return channel, so can be turned down/up there anyway.
Btw. it is not so much different from a lot of guitar outputs from hot pickups.
 
Silly question - but despite the 'instrument' input and the -20/-30dB labelling, have you actually tired it on your line outs? If your line outs are the usual unbalanced .775V level, then I'd bet that the design will be quite happy taking your send output with the level control on the fx unit kept down low. Back then, things in general were a lot less well specified in terms of level, and input level controls were often just across the input, gradually moving the wiper towards ground - so no active components before the level control - just resistor networks to set the working level. Most gear from that period would take a guitar at higher settings, keyboards at around the middle and a cassette desk line at the lower settings. I suggest you give to a go and see. If the line is just too hot, you could build a pad network into a jack plug that will sort it out, but I suspect you won't need it!


actually not :) i was just not sure that it'd be safe to plug in a line level source, i will give it a test later this week and see how it goes.

thanks !
 
Perfectly safe.

Your outputs appear to be line level.

Your inputs? You should just try them. If you had a manual it would be easy to ascertain if they actually accommodate line level, but in absence of that just start with zero to extremely low output on your line level source. Does that make sense? If the inputs are actually mic level, then a line level source will overload them quickly because line level is a much hotter nominal standard than mic level. So just keep your source hushed and then turn it up just a little. If you can't really turn up the source without it being really loud to the effect box input, then it's mic level and surgery will be required.

I suspect your inputs accommodate line level. My Roland DC-30 analog chorus/delay box from around the same time has inputs labeled mic/instrument with switchable -50/-35/-20 pad. The -50 is for mics, -35 for guitar, and -20 for "electric organ". :cool:

I bet if you use the -20 input jack on yours it will be just ducky-fine with a line level source.
 
Rather than mod it, you could get an attenuator pad if it really, really does need a lower input level.
 
Rightio..just wanted to be on the safe side
gonna post a few recordings using it later this month..iv'e got a project coming up.

cheers guys
 
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