Got another question for anyone who's nice enough to school me.

I got a vintage Marantz 2235B receiver for my 2.0 stereo setup. Will likely be purchasing an EP350 sub for it, and will need to use the RCA pre-amp out connections and a Y-cable to connect to the subwoofer's 1/4" phone-input, as my receiver has no other subwoofer outputs (and i doubt high/speaker-level output would be preferable).

Here are my questions:

1. What knobs on my receiver (volume and/or bass/mid/treble), if any, will affect/control my subwoofer? Or as I turn up the volume on the receiver, will I need to turn up the volume on the subwoofer to match?

2. If the bass control knob on my receiver DOESN'T affect the subwoofer, i think that'd be GOOD thing, right? Then I'd have an easier time blending my M3 speaker bass with the EP350 which only has 80Hz and 150Hz cross-over settings. At 80Hz on the subwoofer, perhaps it would be optimal to surpress the bass setting a little on the M3s?

Thoughts, anyone?

1. No, it won't, and yes, you will.
2. Nah, I'd leave 'em alone.

OK, all the rest of you lurking Marantz owners, I know you're there. You might as well come out now. <points flashlight into the virtual bushes>

::and accidently sees someones' Sher-Wood and NADs while they're trying to make little Harmons with Karman::

Okay, now I see that after replying to your other thread that you did have more questions. Keep in mind that since your 2235 doesn't have a separate output for low frequencies to the sub, it's going to be sending the same signals to the sub as go to the main speakers. Therefore the same controls which affect the signals to the mains have to affect the same ones when they go to the sub. The bass/mid/treble tone controls do this, although of course the mid and treble won't make a meaningful effect on the low bass frequencies which the sub will play. Likewise, when you increase the volume to the mains this simultaneously increases the volume to the sub, so there's no need to change the volume control on the back of the sub.

This makes your question 2. pretty much moot, but as I said in your other thread, the 80Hz setting on the sub would provide a reasonably good blend with the M3s, so it shouldn't be a major concern.

You don't want to Y the left and right channels together. That's actually causing one channel's output to feed back into the other.

You'll need to find a line-level summing box. Something that's designed to mix two channels together without allowing them to feed back.

EDIT: I saw John mentioned the same thing in the other thread.

Hi John,

So... about the volume and bass/mid/treble knobs on my receiver, while the subwoofer is attached to the receiver's pre-amp outputs, you are disagreeing with what Ken said earlier, is that right? You're saying that they WILL affect the subwoofer and M3 speakers simultaneously, is that right?

About the Y cable... thanks for catching that, clubNeon (and John in my parrellel thread)! I already ordered a coaxial sub-cable with matching Y-adapter... should arrive any day now. At least I should still be able to make use of the main length of it, without the Y adapter. I'll have to look into that line-level summing box... but sounds like it could be pricier than I'd hoped just to make a darn connection! lol On that note, what about this...

http://www.audiokarma.org/forums/showthread.php?p=3928377#post3928377

It's a link to a year old thread of mine, regarding the stereo-Phone output of my Marantz (does NOT silence the speakers when used!) It's connected to my 'computer' subwoofer (which is why I'm upgrading!), currently. One receiver output, one subwoofer input - job done! Is that JUST as good as using the pre-amp outputs (with summing box) to the subwoofer's 1/4" Phone? All I'd need is another adapter from RCA to Phone for the Marantz end of the cable if that's the case! Those common to find at The Source or wherever?

Thanks for all the help from each of you!

Yes, that's right. It doesn't make any difference where the signals go to after they leave the 2235; they've already been processed by the tone controls, volume control, etc.

Again, the simplest thing is to just make the speaker wire connection; there's no disadvantage in doing so with the equipment you have. You could use just the one coaxial cable from either the left or right channel, but there's some possibility that a part of the bass from the other channel wouldn't be used, even though there's very little "stereo bass" in recordings and the sub frequencies are essentially non-directional.

Using a mono 1/4" plug into a stereo jack still is shorting the two channels together. I actually blew the left channel out of an old sound card plugging a mono headset into it. But other headphone circuits are more forgiving. So it could work (the Y on the RCA could also work), but electrically it's still not the right thing to do.

Most music has the low bass mixed in mono, so driving your sub from just the left RCA will still get you most of the bass information. Then you can get a second sub and run it from the right. (Or the summing box.)

if you were to buy a sub with hi level inputs and outputs, that would be ideal (and simple) in your case, but the EP350 only has hi level inputs.

Oh contraire, I have EP350 and it has both high and low level inputs.

He's just use a pair of speaker wires from each of the output terminals on the receiver (Y-ing to split is OK, it's Y-ing to combine that's the issue). Run one set of high level outputs to the sub, set the sub's low-pass filter ("crossover") to 80 Hz, and then run the second set of wires to the speakers. Their natural roll off will blend in with the sub's filter.

There's not much one can do with a receiver that has no in built provisions for a sub-woofer.

He's saying high level in and out, not just in. I'm also assuming an actual cross-over, and not just a low-pass filter. That way the sub can control what signal gets passed on to the speakers, rather than the full frequency range.

A speaker cabinet, and driver does constitute a band-pass filter anyway. It's more a matter of getting a smooth match between the two (the electrical filter in the sub, and the physical filter in the speaker).

you better reread my post.

until i get a new prepro, i'm running separate preamp and power amp.
They're from the 1980s and don't have a sub out.
the simplest way to make connections in my case was using the high level inputs AND outputs (speakers connectors on the sub):
Power amp TO sub's high level inputs;
Sub's high level outputs TO main speakers.
when done, i adjust the sub level with the level control on the sub to match the main speakers' levels.
You also need to adjust the crossover freq. on the sub itself for a "best match".

speaker wire needs to be used for those connections.

Okie doke... I'm going to need some help to clarify in my mind, what's been discussed here, and add a few new queries while I'm at it!

1. JohnK... One thing I do NOT intend to do, if possible, is to lose any bass signal in either left or right channels from getting to the subwoofer. If i need to use high/speaker-level inputs for that, than so be it. But please confirm for me, if by doing so, the subwoofer will receive ALL the info it needs to perform at it's peak (and perhaps more than needed, in the higher frequencies), and that there will be NO loss in volume output, as it will still run off of it's own amp with no handicap from using high/speaker-level inputs... correct?

2. Also, please verify, by using high/speaker-level in the manner that has been suggested (speakers branch from receiver, subwoofer branches from receiver - speakers do NOT branch from subwoofer)... that the speakers run off of the receiver's amp, and the subwoofer runs off of its own amp, correct?

3. Additionally... my receiver has main left/right speaker outputs and 'remote' left/right speaker outputs, with a front panel 'remote' on/off button. I should be able to connect the subwoofer to these 'remote' speaker outputs, and avoid 'sharing/crossing' speaker and subwoofer speaker-wire wires in the same slots, correct? Would give me a nice 'off' mechanism too!

4. Everyone always talks about getting sheilded coaxial subwoofer cable. If I use speaker wire, there won't be any shielding. Is shielding, for some reason, suddenly a non-issue with speaker wire?

5. ClubNeon, earlier you responded to the what-if I connected my receiver's stereo-headphone-jack output to the subwoofer's 1/4" phone (stereo-headphone-jack, essentially, no?) input. You suggested that would be a worrisome strategy. But... isn't the subwoofer itself able to convert stereo signal to mono, internally? After all, isn't that what it does when you use separate high/speaker-level inputs on the subwoofer? And it would give me the chance to feel I didn't totally waste my money on that nice RCA cable (and y-adapter) i ordered (assuming I buy a 2nd 'phone-adapter' for the receiver end). Hmmm... i guess what you were suggesting is that it's converted to mono IMMEDIATELY upon entering the single RCA cable, rather than when it gets to the subwoofer... but can the current/short jump backwards into the receiver's phone jack - without a 2nd cable available to physically loop back, as in the case with the RCA Y-adapter attached to the 2 Pre-amp outputs on the receiver? Hmmm... do my questions even make any sense at this point? I'm so out of my element here, lol.

6. JB, your setup is the kind that I got a bad impression from, hearing tidbits discussed here and there online. In your setup, is there a point to having a main amp? I might be wrong, but if your subwoofer has its own internal amp, won't it ignore any power coming from your main amp? And since your speakers are attached to your subwoofer, won't they draw their power from the subwoofer (and not your main amp), hence draining some energy from the subwoofer that the subwoofer possibly could have used for itself? In all of that... the main amp would be useless, except for sending the audio signal itself. Again, I'm a naive noob, so what do I know! lol

Great discussion, very informative!

Quote: "4. Everyone always talks about getting sheilded coaxial subwoofer cable. If I use speaker wire, there won't be any shielding. Is shielding, for some reason, suddenly a non-issue with speaker wire?"

I've had sound systems since the mid 80s, and i've never had any interference of any kind by using ordinary 2 wire cable for all my speakers. it does not mean it never happens.

On number 4, it's probably not a problem because low level inputs have much lower voltage than high level (ie speaker level) inputs, and are therefore more susceptible to interference.

Quote: "6. JB, your setup is the kind that I got a bad impression from, hearing tidbits discussed here and there online. In your setup, is there a point to having a main amp? I might be wrong, but if your subwoofer has its own internal amp, won't it ignore any power coming from your main amp? And since your speakers are attached to your subwoofer, won't they draw their power from the subwoofer (and not your main amp), hence draining some energy from the subwoofer that the subwoofer possibly could have used for itself? In all of that... the main amp would be useless, except for sending the audio signal itself. Again, I'm a naive noob, so what do I know! lol"

i will try to make this as clear as i can.
speaker (high) level signals come out from the main amp and go to the sub high level inputs.
from there, the signal is divided in 2 parts by the sub's crossover; one becomes the Low Freq. signal that goes to the sub's internal amp, and the other one contains only signals above the sub's crossover point and that signal goes to the front speakers at the same level it had when going out of the main amp.

done this way, the main speakers receive the signals stripped of the frequencies below the crossover point,
and the sub receives only the low frequencies below the crossover point.

if the crossover is set to, let's say 100 Hz, then the sub will reproduce, with it's own amp, the frequencies below 100 Hz,
and the main speaker will receive all the frequencies above 100 Hz. from the main amp output to the speakers.
this is a simplified explanation.

Quote: "6. JB, your setup is the kind that I got a bad impression from, hearing tidbits discussed here and there online."

Please explain what you mean.

Okay GC; this discussion is still a bit tangled-up with terminology. Again, subs don't have internal crossovers; the speakers get a full-range signal even when they're connected through the sub. The low-pass filter in the sub rolls off the sub driver response above the selected frequency on the control(sometimes labeled as "crossover"), but has no effect on the mains. A very few subs have a separate high-pass filter, typically fixed at around 100Hz, on their speaker level outputs which affects the mains if they're connected in that way, but this has nothing to do with the sub's low-pass filter and its frequency control.

1. When connected to your 2235 with speaker wires, the sub gets all frequency content in both channels and the internal low-pass filter then rolls it off above 80Hz when that setting is selected.

2. Yes, the receiver power goes straight to the mains, regardless of whether the mains are connected through the sub. The sub amp can only power the sub driver; it has nothing to do with the mains.

3. Not familiar enough with the 2235 to discuss that "remote" provision, but again, use the speaker wire connection and don't worry about it.

4. Yes, shielding is essentially a non-issue with speaker wire. The current carried is far greater than that on line-level coaxial cables and isn't audibly affected by weak external interference.

Re 3., I was able to find a picture of the back of the 2335 and I see the second set of speaker terminals for "remote" speakers. So yes, as long as your manual says that you can use both sets of terminals simultaneously, you could connect the sub wires to the "remote" terminals instead of jamming them into the main terminals.

J.B.... I guess I got a bad impression of high-level sub setups because no on seems to be using them for the most part, if given a choice, and I recall one guy writing about being content with his speaker-level setup for 2 years until one day he removed his speakers from the sub and attached them directly to the main amp and was blown away by the improved performance. I thought, dang, those speakers weren't getting the proper wattage passed along for 2 whole years... what a sunk cost in time!

Thanks for all your words of advice Ken, JohnK, ClubNeon and JB... it's been quite informative. I went and ordered the EP400 in the end. Thanks again!

I'm just waiting to get a new pre/pro to use high level connectors instead of spkr connectors.
in the meantime, my sound is crystal clear, as long as the Dolby Surround Processor is off; when it's on, the surround effect is only acceptable and sometimes there is distortion too.

i would be surprised if some of the wattage gets lost; if it were so, then voltage measurements at the speaker inputs both before and after installing the sub would be different; yet, i get the same voltage, which means the same Wattage.
Also, a wattage "leak" somewhere in the sub would probably heat up the insides of a sub and maybe damage the sub's amp.

do you agree?

J.B., of course that's true, since as was pointed out above, the receiver connection to the mains runs straight through the sub to the mains, essentially the same electrically as if the wires ran directly from the receiver terminals to the main speaker terminals. There's no mechanism by which any power could be "lost".

There's in effect an internal "Y" inside the sub with one branch going into the sub amp and the other going straight to the high-level outputs. The input impedance of the sub amp is on the order of tens of thousands of ohms and practically zero power can get through that.

*hissss*

AAAAAAH!

<drops flashlight>
<runs away>