From 4 ohm to 2 ohm back to 4 ohm resulted in loss of power.

[Wolfenit415]

Hello, new guy here. Thanks to anyone who takes the time to read this and post a reply, it is much appreciated as I'm racking my mind for the last 2 days. To make a long story short, i recently bought a budget system. This system includes a Rockford Fosgate R250X1 Prime 1-Channel Mono Block Amplifier, 2 Rockford Fosgate Prime R1S410 R1 10-Inch 150 Watt Subwoofer - 4 Ohm, a ported Bassworx box and a Kenwood KDC-MP345U HU. (found out later the subs are not recommended for a ported box) This setup ran very well for the first week. The subs had very natural sound and didn't take much to make them hit well. The punch EQ knob on the sub wasn't used, just the remote knob at the helm. Gain just about half way. Hz on head unit set at 85 (turned all the way up on the amp so to bypass it). Ok, so decided because the amp is stable at 2 ohms i'd give a try wiring the subs in parallel and get a lil more power to them. The way i ran it was amp+ to SP1+ to SP2+ then amp- to SP1- to SP2-. Once everything was hooked up i turned it on and played the typical music i play such as BassNectar or DeadMau5, you know tech stuff.//content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif Instantly i noticed there was a significant loss in sound quality, the subs sounded like they were hitting a brick wall. I backed the gain down a lil and no matter what i couldn't get them to sound very good, i was prepared for small loss in sound quality as i had read this prior, but this was ridiculous. I went and rewired the subs back to 4 ohm or a typical dual sub box wiring. Hooked back up and ready to thump aaanndd notta. The subs and amp had power, the subs made bass but nothing like it was previous to my rewiring. So thinking i wired out of phase, i took it all back apart and rewired again taking special care in everything i did, same. This morning, thinking i may have damaged the amp, i returned and replaced with a brand new one, no luck same sound. So to put it in to perspective if before my 2 ohm wiring i could turn the HU to say level 18, it pounded! Clear crisp bass that rattled my mirrors all over the place. To now when i put the same level on i get maybe half the bass. I've checked and rechecked my ground, power cable, rca's all of it. I spoke to a Rockford tech and his idea might be that for whatever reason giving them that extra power in a ported box may have caused them to go into over excursion. Well that's the story if anybody could give an idea that'd be great as of now i'm thinking i may need to just buy new subs. Better ones obviously.

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[mrclean636 10+ year member]

Gees that's no good man, and yeah those subs are no recommended for a ported box, specially since the amp does not have a subsonic filter.

Um.. also, with two, single voice coil, 4-ohm subs, you can wire them to a 2-ohm load or a 8-ohm load at the amp. You can't run a 4-ohm load at the amp with two single voice coil 4-ohm subs.

Example:

Two SVC 4-Ohm Wiring = 2-Ohm

Two SVC 4-Ohm Wiring = 8-Ohm

 

[Wolfenit415]

Hey there friend thanks for the reply. I just recently learned that i had the subs ran at 2 ohms on the amp. This just isn't something i realized. I'm fairly new to this and your post confirms this. I guess this is something that could all really be in my head? Maybe i'm just getting used to it. Now its recently been getting hot here where i live. I assume the difference in temps on the car metal and plastic could have something to do with the way the rear view mirror had been rocking and rolling before. Maybe with everything being warm its just more pliable and less prone to vibrations? So in all reality all i did is run them into 2 ohm a different way? How i have them now is back the way they were originally. A speaker on the left and the right each end of the box has a spring loaded pos and neg terminal. I had each speaker wired to the respective terminals inside the box, then the wires ran outside the box from the pos and neg were twisted to their respective wire and then inserted into the amp to the pos and negative. So i am correct in realizing that this is a 2 ohm load. Thanks again! Sorry if i sound silly. My hearing isn't the best and sometimes i think i'm missing a lot.

 

[blazeplacid 10+ year member]

what you described is parallel wiring...so yes its a 2 ohm final impedance

 

[Wolfenit415]

Shoot, well then i probably am going crazy and had some kind of placebo effect. Thinking it was one way, then thinking i ran another and then back. Would having the windows down make that much of a difference, or just getting used to it. I know their isn't any way for you guys to be able to tell me a difference in sound because no one was around before or after lol. Could running them a different way caused anything serious? Alsssooo i think i may have had the gain just slightly to high for only a few mins. How long would it take to cause some sort of voice coil damage. I honestly have spent 2 full days and come across tons of posts about similar situations (meaning someone feeling as though they have lost sound quality)//content.invisioncic.com/y282845/emoticons/fro.gif.c695f1f814b01c4ad99fe7f8cccadd29.gif nothing that quite satisfied me as an answer.

 

[blazeplacid 10+ year member]

everything you do makes small to large changes

usually open windows = moving more air = louder to the ear

night time driving usually sounds louder because there are less things around to make noise

also what source are you using?

Store bought cds or ipod/usb usually sound the best in terms of quality of sound.

Aux inputs are hit or miss and XM radio is usually the worst signal

another thing is the way the music was ripped (if you are using ipod/usb)

some rips sound terrible no matter what you do

 

[Wolfenit415]

Before i started all this and it was originally hooked up i was using my HTC ONE X android, using music from google play store. I believe the quality is 320kbps. Sounded really clear and lots of solid bass from music such as Bassnectars- Upside Down. I use a Monster brand Aux cable from the earjack to the input. Hardly use the radio and knew there is a diff in the two. Never used a cd in this setup until today and tried Marshall Mathers LP. Using a Kenwood HU. Originally, the bass control knob by my steering wheel, there was absolutely no reason to turn it up past half because everything was so loud and shaky (in a good way). Once i kind of got over the "I have to make everything move" phase i had it mostly at the quarter turn. Gain was half way, eq punch knob not used. After all this i now have to have the bass knob up all the way. I still dont get that car/body shaking as i did before. Now its more like as if the sensitivity of the speakers has dropped so id have to give more power to achieve the same result. The bass seems more punchy as opposed to boomy?//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[Wolfenit415]

Ok, so today i went for a ride on the expressway about twenty mins or so. I noticed a huge improvement in my bass response is this related somehow?

 

[mrclean636 10+ year member]

Ok, so today i went for a ride on the expressway about twenty mins or so. I noticed a huge improvement in my bass response is this related somehow?

More output from your alternator

 

[Wolfenit415]

Ok, so after all this hubbub it all boils down to the fricking box. I returned the ported box and got a sealed box. WOW! I guess when the manufacturer says a sub is not recommended for a ported box, they mean it! The difference is night and day. I mean i still have kind of a small system so i have to turn the bass up a bit but man its amazing. If i sound a lil nutty its because this is my first system. The people at abc warehouse should have known this about the subs and sold me a correct box, but oh well. They looked at me like i was crazy when i told them what the Rockford techs told me about the setup. Live and learn! I have literally learned so much in the past week trying to figure out exactly what was wrong with my setup. Thanks to the few that have helped me along the way! Edit: I guess i have a small question. This sealed box is actually two separate boxes, which i have no problem with, and are slightly used. One has a small hole that i can hear a whistle through when i push on the sub. Is this going to make a huge difference? Is it imperative that i plug this hole immediately? How much of a difference will it make between the sound in the 2 subs? Thanks!