Isolate pin 1 from pin 3,(driving hi and lo single ended without the ground) and see what happens. It may be a "real" balanced input vs. a "servo-balanced" input and might not like the ground tie.
It might also have some functionality issues.
I got this Altec 1652b EQ cheap and untested. I have tried hooking it is via XLR in and out (XLR in is via a RCA jumper pins 1,3 connected to the negative side and pin 2 to the positive side). I get no output. Is there a jumper or something I have to install across the barrier strip or are those just extra inputs?
I hear a relay click after I turn it on. I am assuming that is a protection circuit.
Isolate pin 1 from pin 3,(driving hi and lo single ended without the ground) and see what happens. It may be a "real" balanced input vs. a "servo-balanced" input and might not like the ground tie.
It might also have some functionality issues.
Not all vegetables make good leaders.
I'll have to try some different hookup options. I had read somewhere about some EQ's with the barrier strip needing two pins jumpered to work. Thats probably not the case with this one.
This came from a "working setup" but I did not personally test it. I got it for dirt cheap so I took a gamble. It might have some issues. I am optomistic since the relay clicks
hello,try taking the top cover off and see if there are any peerless transformers installed in the octal sockets.if not,check to see if the octal sockets are properly strapped with jumper straps,two per socket if i remember correctly.hope this helps.c.darrell freemanOriginally Posted by Elitopus1
I'll have to try some different hookup options. I had read somewhere about some EQ's with the barrier strip needing two pins jumpered to work. Thats probably not the case with this one.
This came from a "working setup" but I did not personally test it. I got it for dirt cheap so I took a gamble. It might have some issues. I am optomistic since the relay clicks
Ok I popped the top and found the octal sockets. Looks like each one has two jumpers.
I am going to try some more hookup configs. If that doesnt work I would think this unit is not functioning
UPDATE: I unhooked 1,3 and just hooked up to the HI and LO on the barrier strip. It works! Thanks for the help everyone
Last edited by Elitopus1; August 25th, 2016 at 09:57 AM.
On many audio forums, especially that big blue one, you'll see as a matter of course it's advised to tie pins 1 and 3 together when connecting single ended gear to balanced gear. I say "not so fast grasshopper"UPDATE: I unhooked 1,3 and just hooked up to the HI and LO on the barrier strip. It works! Thanks for the help everyone
This will work fine for "servo-balanced" gear the likes of which are produced by Aphex, Ashly, BBE, Behringer, DBX under the Harman umbrella, Rane, and probably a dozen other manufacturers. The output is split between two opamps each handling one half of the signal(+ or -), and the feedback paths are arranged such that shorting either + or - to gnd causes the other op-amp to kick up it's output preventing the 6db attenuation that otherwise occurs.
When you're dealing with older pro level gear that is balanced, you have to be prepared to take the hit in signal attenuation when splitting a balanced line into a single end, and if you short either half of the signal to gnd, expect undesirable things to happen.
With older balanced gear it's also a good idea to verify the pin-out as well. Pin 2 hot has not always been a "standard", and you will encounter some gear that used a pin 3 hot wiring convention.
Not all vegetables make good leaders.
Thanks Tom. I don't have much experience with the older pro gear. Honestly I did have to look up how to convert RCA to XLR. Everything I saw showed pins 1 and 3 shorted together. Thanks for mentioning that that could be the problem.
The EQ sounds nice. I am still trying to decide if I want to use it to slightly shape the sound of my Vott's or if I want to use a passive EQ network like the 30904. Running them with recapped N801-8a crossovers they have a little too much mids for me. I like to add a little bit down low and up top.
I have had this EQ hooked up in my system until yesterday. When I turned on the stereo yesterday the cone almost jumped out of my left 604. I of course had the volume on the preamp at zero but the gain on the Ashly was up about half way. The EQ has a bad oscillation on the left channel. I verified it is not the connections. Luckily when I bipassed the EQ everything still works great.
So now when I get some time I need to pop the cover off the EQ and see if there is anything obviously wrong inside. If its not an easy fix it will just get put on the shelf.
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Maybe its time to go digital. I'm sure one of the newer Ashly or Behringer units would be a step up
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