2 subs, did I do this right?

66chevyIISS

I have hooked up two subs to my 1 pre out. I had to use two y cables to make this work.

My polk sub has two rca inputs while my other sub is only a single. I used a y cord to run the single sub then plug another y cord into the other side for the polk sub. It seems to be working ok, but do you think this will take away from my polk? the 2nd sub is only a 6". Can I damage anything doing this?

Like so lol:

Sherardp

nice setup u have there. just make sure you calibrate your setup.

engtaz

Depending on the sub (IE-1-15"and 1-12) you should adjust you crossovers manually on the sub then proceed to adjust the gains.

engtaz

Schwingding

You probably don't need the 2nd line connection into your Polk sub. Most subs only require one - the LFE output from your AVR is only a single channel. The dual connections are generally available for those who use the speaker or line level right and left channel outputs into their subs. You are using the LFE output so the 2nd channel addition (and the 2nd Y) are worthless in this case. You may input that single LFE channel into either the left or right channel input on the sub.

When you have them connected, use your SPL (a must have for dual sub calibration) to adjust the subs as follows:

Adjust your mains to a reference decibel level (I use 75db) using your receiver's test tones. Then turn on one sub only. Using the same test tones, adjust that sub to the same reference level. Turn that sub off and turn the other one on. Adjust it to the same reference level. Then turn both on, and go into the receiver's level adjustments, and adjust the sub/LFE channel so that both subs are outputting to the reference level. You'll have to drop it by probably 3 or 4 decibels with both on. Many people like their subs to run a bit hot so you may want to leave it there, but reference level is where you should start your process.

We can worry about phase adjustments when you have the above taken care of.

66chevyIISS

My setup was calibrated to 85db using Avia. I re-checked the subs after hooking up the 2nd and I calibrated them to 85db as well. I ended up at -3db on SW I believe. I did not do them individually though. That makes sense to do it that way. I will re-cal tonight and see if the outcome is different. What should the low pass be set to when dialing in to 85db? should I adjust that after or during?

I tried just using 1 line on the Polk sub and it seemed to not be as loud. Maybe I was just getting that illusion. I will test it both ways again.

As for Phase, I would love a crash course on this. I really don't understand the phase part. I just leave it on 180.

PolkThug

66chevyIISS wrote: »

I tried just using 1 line on the Polk sub and it seemed to not be as loud. Maybe I was just getting that illusion. I will test it both ways again.

It's no illusion, that's the way it works,you just have to adjust your gains or levels again.

Schwingding

Both cables in (from the same channel) as you have had yours set will increase the output, but you won't really gain anything from it, as reference level is still reference level. You're still amplifying the same channel, just the amp is seeing it from two sources. When setting the sub levels, you'll adjust the gain (as described by polkthug) anyway to get it back down to where it should be. Extra/unnecessary cable interruptions, such as your Y splitter, should be avoided in the signal path wherever possible. Each time the cable is cut a measurable signal loss is created.

66chevyIISS

Ok I got them both dialed in equally at 85db. Now what?

side question: I think I want to pull my sectional away from the wall and put the slimmer sub behind it. If I run the cable in wall I will need about 30 feet. I've bought all my cables through monoprice and have been happy with them. They only sell 25 and 50ft though. Will I be ok running this 50 feet coaxial? High-quality Digital Coaxial Audio RCA CL2 Rated Cable - RG6/U 75ohm S/PDIF Subwoofer - 50ft CL2 is ok for in wall right? I could buy the 25ft and run it under my basetrim as well if that is a better option.

Schwingding

50 feet is a long cable, but I run a 50 foot cable to one of my subs, too - and its from monoprice. Sometimes ya gotta do what ya gots to do.

66chevyIISS

My cables came this weekend. Once again monoprice comes through. Great quality for the price.

Placed the sub behind the couch and what a difference it made! Even using 50 ft cable.

The downside is I had to move the couch closer to the screen by about 9". I might have to re-size the screen down to around 126"

Cursed1

66chevyIISS wrote: »

My cables came this weekend. Once again monoprice comes through. Great quality for the price.

Placed the sub behind the couch and what a difference it made! Even using 50 ft cable.

The downside is I had to move the couch closer to the screen by about 9". I might have to re-size the screen down to around 126"

Sorry for the change of topic. Any pics of the car? Love the Chevy II

66chevyIISS

Sure I'd rather show pics of my car then my home A/V lol. Car is my first hobby.

Pic 1

Pic 2

Engine

PolkThug

66chevyIISS

Lmao

Face

Very clean!
So what's she run?

engtaz

Nice

engtaz

66chevyIISS

Face wrote: »

Very clean!
So what's she run?

I had just got my car running last spring after changing a bunch of things and on my first pass I broke my driveshaft at the finish line. It destroyed a bunch of parts. I didn't get to make another pass after that.

I ran my best pass 12.25@111 with a granny launch at the starting line. With a full launch on the converter I'm hoping for 11.8's once I get the kinks worked out.

Here is a video of that pass:
Drag Video

This was the aftermath:

broken driveshaft
Broken transmission
Smashed exhaust + dented floor

Face

At least you still beat the mustang.
Best of luck getting everything worked out.

Cursed1

66chevyIISS wrote: »

Sure I'd rather show pics of my car then my home A/V lol. Car is my first hobby.

Pic 1

Pic 2

Engine

Looks super clean. What's in the garage 55 or 57?

I tried to buy a 67 back last fall. Guy decided to keep it. I love the Nova's.

66chevyIISS

That's my dads 57. You should try to buy antother one!