Need a new solution for an old problem

mcnally13

Hi folks, here is my dilemma. I have recently purchased an RMS-250 subwoofer, and have a pair of R10 bookshelf speakers. I am using a vintage Yamaha CR660 receiver to run them. I do not want to use the speaker level inputs for the subwoofer, as i am afraid of sound degredation, and this receiver does not have a sub-out connection <obviously> It does however, have a couple of tape monitor loops, which are unfiltered, whole range of sound is sent to sub, and i also have a pre-out. However, when I plug the Sub inti the pre-out, I seem to get no sound whatsoever from the receiver or sub, or bookshelf speakers. The pre-out, main in has a coupler switch, which i leave in the default position, ON. So, can anyone help me figure out the proper way to set this up for maximum sounds quality and with no possible danger to the components of either the sub or the receiver?

Thanks folks

sgtgto

HI:

Have you tried connecting one of the tape monitor outs, on the receiver, to the two lfe ins on the sub. You will have to activate the tape monitor for it to work. True, you get a full range signal but the sub will work at whatever range you set it to, mine goes from 60 to 180 Hz. Set it to around 100Hz, or whatever setting you like best. The sub will do the rest. If you set it to 100Hz, only frequencies below 100Hz will go to the sub and so on.

Let me know if it works.

Gary

JohanK

The tape out is no good since it is a fixed level signal; i.e. level does not change when you move the volume knob.

I believe you can use the preout/main ins. Run interconnects from preout into sub L/R ins and then run interconnects from sub L/R out back into the main ins. I'm not familiar with your receiver but I think the coupler switch should be in OFF for this method; i.e. no direct connection b/t preouts and main ins, connection is made with cabling through sub RCA ins and outs. I'm only familiar with the jumpers when receivers have preouts/main ins.

sgtgto

Hi:

I disagree. The output doesn't have to be controlled by the volumn control on the receiver. It has a line out signal, not amplified, same as the lfe out on a receiver. The only difference being that in a true line out condition the whole frequency range is present at the output whereas the lfe output has a cutoff somewhere around 100 Hz. It may also be filtered.That is where my receiver cuts off. The sub amp and volumn control the dynamics, or you would not need an amp in the sub. In other words, if you run a line level signal into your sub, you control what comes out with the sub volumn control and crossover frequency control knob on the sub.

One thing I forgot to mention. Use an RCA-Y-cable from the tape out or record out of the receiver left and right. Run one leg to the tape deck record in and the other to the sub lfe in. You need a Y connector for both Rt and Lft channel of the rec out on the receiver. When you activate the tape monitor control the sub should work. It has been a while since I have used this function so just try it and see if it works for you. Can't hurt anything.

Another way that I am almost sure will work. If your tape deck has a headphone connection, use a 1/4" stereo jack to tape deck headphone out jack with RCA Left and Right on the other end. Connect this to the lfe connectors on the sub. Turn on the deck, put in a tape and push the record button, you don't have to push play, just record. Use the record level adj on the deck to adjust the signal to the sub so you don't overdrive it. This is jury rigging but try it.


Gary:p

mcnally13

Thanx all, I appreciate the suggestions, Ill try them and see which comes out with the best sound. Just wanted to see what other options I may have had. Let ya know how it turns out!!

:-D

JMC

JohanK

The output doesn't have to be controlled by the volumn control on the receiver.

Doesn't have to be but it is inconvenient if it isn't.

In other words, if you run a line level signal into your sub, you control what comes out with the sub volumn control and crossover frequency control knob on the sub.

This would work but you would have to move volume knob of the sub whenever you wanted to change the system's volume; again, inconvenient.

[Deleted User]

Hello,
On the Yamaha receivers there is usually a metal "U" shaped link that joins the pre-amp out with the main amplifier input. Once these "U" links are removed the internal amp no longer receives a signal. This is why there was no audio from the main speakers. You would need two "Y" cables with a male RCA on the base, a male RCA on one of the branches and a female RCA on the remaining branch ("Y" cables come in different variations on the connectors on the three ends). Then, plug the male RCA connection on the base of the "Y" into the pre-amp output. Then connect the branch with the male RCA into the main amp input on the Yamaha. This will re-establish the pre-amp/power amp connection for the Yamaha's requirement. The remaining female branch of the "Y" can be used to connect to the RCA cables which go to the sub-woofer. Since this pre-amp connection is "downstream" of the receiver's volume control, you will be able to turn the receiver's volume up and down without having to adjust the levels on the sub-woofer.
I hope this is helpful information.
Regards, Ken Swauger