Horrible sounds from equalizer

[celinaa]

Hello, all.

I finally have a preamp with tape loops (yay!). I have put an equalizer in the tape loop…but I am having problems.

I believe I have it set up correctly. The tape out from the preamp goes to the input on the equalizer…and the output on the equalizer goes to the tape in on the preamp. There is also a tape monitor button, and when I press this button, the equalizer is applied. Perfect.

The problem is when I select Tape as the SOURCE on the preamp. (I understand that selecting Tape as a source makes no sense with this setup, but this is unavoidable for at least a second due to the preamp’s design when changing sources).

When I select tape as a SOURCE on the preamp, and the equalizer isn’t flat (in this case, the low bass was boosted), I get a HORRIBLE, LOUD, speaker destroying sort of low pulsing sound. I tried two different equalizers and had the same result. This is both with and without the preamp’s tape monitor button engaged.

I theorize that it is feedback…the sound of the EQ circuit is going into the preamp, out to the EQ, into the preamp, out to the EQ, etc - and creating a horrible feedback loop. Am I right? What can I do? Does the presence of tape as a source (not just the monitor loop) mean I can’t use an EQ in the tape loop?

Preamp is an Akitika PR-102.

Thank you!

 

[NTK]

Welcome to ASR!

My electronics skill is totally amateurish, so hopefully someone more knowledgeable than me can chime in if I'm mistaken here.

I think you are correct that if you select Tape as the source, the system will go into feedback. (Tape In feeds the Tape Monitor Out, and the Tape Monitor Out goes to the Equalizer In, the Equalizer Out goes back to the Tape In, completing the positive feedback back loop!)

I think the easiest, which may not necessarily be desirable for you, is to simply place the equalizer in between the pre-amp and power amp (or powered speakers).

Pictures taken from the manual: https://www.akitika.com/documents/AssemblyManualPR102Rev1p17.pdf

 

[sophia97]

but this is unavoidable for at least a second due to the preamp’s design when changing sources). sonnerie gratuite

Does this apply to both the indirect/serial source selection via the front panel buttons and the direct source selection via the buttons on the remote control? And does the problem also occur, if you temporarily select the other tape monitor (i.e. the one, to which the EQ isn't connected) during the source selection?

 

[M67a2]

I had the same thing happen using my pioneer Sr 202 reverb through the tape monitor on my Akitika. It blew out my dynaco vta amplifier.
Unpollerized plugs??? What caused it?

 

[M67a2]

Does this apply to both the indirect/serial source selection via the front panel buttons and the direct source selection via the buttons on the remote control? And does the problem also occur, if you temporarily select the other tape monitor (i.e. the one, to which the EQ isn't connected) during the source selection?

Hello, all.

I finally have a preamp with tape loops (yay!). I have put an equalizer in the tape loop…but I am having problems.

I believe I have it set up correctly. The tape out from the preamp goes to the input on the equalizer…and the output on the equalizer goes to the tape in on the preamp. There is also a tape monitor button, and when I press this button, the equalizer is applied. Perfect.

The problem is when I select Tape as the SOURCE on the preamp. (I understand that selecting Tape as a source makes no sense with this setup, but this is unavoidable for at least a second due to the preamp’s design when changing sources).

When I select tape as a SOURCE on the preamp, and the equalizer isn’t flat (in this case, the low bass was boosted), I get a HORRIBLE, LOUD, speaker destroying sort of low pulsing sound. I tried two different equalizers and had the same result. This is both with and without the preamp’s tape monitor button engaged.

I theorize that it is feedback…the sound of the EQ circuit is going into the preamp, out to the EQ, into the preamp, out to the EQ, etc - and creating a horrible feedback loop. Am I right? What can I do? Does the presence of tape as a source (not just the monitor loop) mean I can’t use an EQ in the tape loop?

Preamp is an Akitika PR-102.

Thank you!

Did you ever

Hello, all.

I finally have a preamp with tape loops (yay!). I have put an equalizer in the tape loop…but I am having problems.

I believe I have it set up correctly. The tape out from the preamp goes to the input on the equalizer…and the output on the equalizer goes to the tape in on the preamp. There is also a tape monitor button, and when I press this button, the equalizer is applied. Perfect.

The problem is when I select Tape as the SOURCE on the preamp. (I understand that selecting Tape as a source makes no sense with this setup, but this is unavoidable for at least a second due to the preamp’s design when changing sources).

When I select tape as a SOURCE on the preamp, and the equalizer isn’t flat (in this case, the low bass was boosted), I get a HORRIBLE, LOUD, speaker destroying sort of low pulsing sound. I tried two different equalizers and had the same result. This is both with and without the preamp’s tape monitor button engaged.

I theorize that it is feedback…the sound of the EQ circuit is going into the preamp, out to the EQ, into the preamp, out to the EQ, etc - and creating a horrible feedback loop. Am I right? What can I do? Does the presence of tape as a source (not just the monitor loop) mean I can’t use an EQ in the tape loop?

Preamp is an Akitika PR-102.

Thank you!

Did you ever figure this out?
I'm afraid to use this thing after killing my $1,500.00 amp.

 

[DVDdoug]

Did you ever figure this out?
I'm afraid to use this thing after killing my $1,500.00 amp.

That shouldn't happen with all preamps (or integrated amps). I seem to remember old preamps & receivers that only had a "tape monitor" switch and no separate "tape-input" switch so you couldn't create a feedback loop that way Or you could have an additional tape-input that's not part of the tape-loop.

 

[restorer-john]

The 'designer' of the thing clearly has no understanding on what a 'tape loop' is.

They have allowed any input to be selected and routed to the tape outs, including the output from the tape deck/processor/eq you are attempting to monitor! Idiots. As the input selector is an up/down, you can't accidentally avoid selecting the input that will cause the feedback, unless you are super careful to go the opposite direction.

There should be logic to prevent you selecting the same monitor as the currently selected input. Contact the designer and find out what went wrong.

Just put the EQ between the source and the preamp or the preamp and the power amp and buy a proper preamplifier with usable tape loops/processor loops and preferably a user controlled rec-out selector.

 

[Doodski]

Just put the EQ between the source and the preamp or the preamp and the power amp and buy a proper preamplifier with usable tape loops/processor loops and preferably a user controlled rec-out selector.

^^^THIS.
@restorer-john is 100% correct in his solution.
Be sure that the EQ has no faults with grounding or scratchy/snappy controls.

 

[sacguy231]

I had a PR-102 and thankfully sold it. It sounded very nice, but I could get an earth-shattering sound/feedback if I accidentally stopped on or chose the input that I was also trying to monitor. Never damaged any gear, but gave me a jump scare once or twice. It was an unacceptable design flaw to me.

 

[Mean & Green]

I would set the volume dial to zero when using the input selector switch. That should prevent any nasty feedback sounds from reaching your speakers and ears.

 

[restorer-john]

If there's no bi-directional tape dubbing options (and it doesn't look there is), there's absolutely no reason to have the Tape 1 and Tape 2 on the input selector at all. Twin tape monitors is all you need.

Just get rid of it before you or someone else destroys another amplifier or an expensive set of speakers/tweeters.

 

[M67a2]

You will probably see it in ebay soon!