Build Log - Street A

7 years 2 months ago #1 by Tezzating
OK I'm creating this thread as a way to keep me motivated and on track. The next event here is Sept. 5th.. which gives me two weeks to do something.

First of all let me say this.. 138.8dB in a CRX with a NEO motor and "1.5Kw" monoblock is NOT acceptable in my CRX. I'm a three times Aussie SMax1-2 champion with certified SPL of 153.6dB FFS and have built another CRX capable of 151.8dB with one 2Kw amp and two 12"s.

Issues:
1. Amp makes 2/3rds of FA power
2. Shaky power systems
3. Box Sucks !
4. Zilch tuning
5. Busto sub with tatty dust cap
6. Source material.. I need a proper tones disk.

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago - 7 years 2 months ago #2 by Tezzating
Solutions:
ONE
- Address power problems
- Setup with CRO/DMM
- Sell Clarion for something regulated ??

TWO
- Get G34 Red Top !
- Train for 13.8V float instead of *gasp* 12.1V float
- Replace OEM earthing with 4g or 0g
- Rust proof OEM earthing points
- Clean earth points with wire brush
- Solder cable into crush lugs
- Add 2 more 0g power runs ?
- Shorten cables into cabin
- Move +ve so I can remove fuse for SPL

THREE
- Hack down from 1.8 cubes to 1.2 cubes
- Re-glue all edges and seal with liquid nails
- Replace CARDBOARD port with PVC
- Flare port ends
- Shift 1x 5" to 2x 4" port
- 45's ?

FOUR
- Beg/Borrow/Steal CRO
- Get access to a meter. ANY meter ! thats not built into my iPhone

FIVE
- Replace dust cap with something.. carbon ?

SIX
- Burn my own damned test tones CD !

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago #3 by Dylan
You forgot SEVEN. 150dB's!

Thought about getting a yellow top instead of a red top?

Maybe get a stronger un regulated amp that you can drop to 1/4 an ohm?
7 years 2 months ago #4 by Tezzating
I can afford a G34 red top.. cant afford a yellow :P Same as amps. Basically, the gear I gots is the gear I gots and thats about the size of it for now.

Trying to keep build costs down (under $1k total).. ya know, prove you dont need to be Leno rich to make big SPL's.

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago - 7 years 2 months ago #5 by Tezzating
Todays update.. is a running costs list:

AMP - $400
SUB - $150
Cable - $70
Lugs - $15
RCA's - $10
Box - $free
HU - $250
Battery - $170

TOTAL $1065


Bought some T bolts ($5) and 4" storm pipes ($19) yesterday to modify the box.

New Total $1089. So OK, I'm technically over budget by $89.. unless you discount the cost of the headunit cos I bought it when I got the car cos it didnt have one ! Which would bring the total down to $839.

So from here on, lets say the expenditure for This Project Only is now at $839. $161 of the budget remains !

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago #6 by Tezzating
Not that it means much but here's the graph for the modified enclosure.. based on some advice from the guy @ team Riprock :P
1.2 cubes (down from 1.8) and a pair of external ports, 4" diameter, 18" long. Exhibits a peak around 60hz :P


The lazy mans signature (TM)
Its Decibelcar.com Baby

This message has an attachment image.
Please log in or register to see it.

7 years 2 months ago #7 by Tezzating
Also need to re-seal the tail lights and trim garnish (gaskets are bad).
SD around the lights and rear panel was recommended.. I'll see what the budget allows :O
Some work around the rear vent areas as well.

Need to refit the glove box (busted hinges).. need an icebox/esky to sit infront of the front seat too ;).

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago - 7 years 2 months ago #8 by Tezzating
SIX is taken care of.. Just burnt our very own Test Tones CD :D

Just picked up a DMM with peak hold, amp clamp, borrowed a single trace CRO. Will do some through testing of this amp and see what it does.

Need to double check this sub, make sure the coils are OK. Will see if the amp will hold 0.5ohm, then try 1ohm (one coil) and see how that works out. If not, I have a line on an L7 12" I could trade out (might be the best move).

Also contemplating selling the Clarion, I've got a line on a used Hifonics Collosus for $400

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago - 7 years 2 months ago #9 by Tezzating
Oh FFS.. had a nice update and then forgot to save it. Here's the brief..

1. Battery isnt very happy. It went under 10.5V trying to start the engine so the whole car lost power.
2. CRO on HU = no clipping @ full volume (with EQ off & Sub @ 0)
3. CRO on MP3 = no clipping (rules out source)
4. Used Tones CD anyway, seems more genuine to use the CD :P
5. Unloaded (using CRO to calibrate SubSonic, XOVER & Gains) the amps seeing 12.0V on the terminals.. massive power drop there
6. No more clipping in amp :)
7. Managed one good run to get power readings as follows:

Input Voltage: 10.5V
Output Voltage: 54.4VAC
Output Current: 14.8AAC
RE: 2.3ohm
Reactive Load: 3.8ohm @ 52hz
Rise: 1.5ohm
Power: 569WRMS

Unloaded, output voltage is 59.6VAC with 12.0V input.. 8.7% output voltage loss with 1.5V input voltage loss.
I've been told 65V output is nominal unloaded.. @ 8.7% gain per 1.5V input increase, 13.5V input should reveal 65V unloaded.

New Battery and refine enclosure are the two priorities right now.. altho I'd also like a XX-Colossus :P

[edit] infact no matter what happens, I'll need a new battery of some kind in the short term.. cant have my car simply not starting !

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago #10 by Dylan
Ooo, lists, I like those!

Good to see you managed to get a CRO. That voltage drop is sad, My money is on that being the cause of the amp protecting at 0.5ohm.
7 years 2 months ago #11 by Tezzating
I'm looking into battery options.. this weekend I'll be pretty much working on the car from sun up to sun set.

Fixing the hinges on the glove box and re-installing it this weekend.. getting a cooler :P from a friend to borrow as well.
Going to remove the padding from the roll cage.. and start work on the tail light area as well.

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago #12 by soccerx6
its good to see your finally making some headway with the equipment!
7 years 2 months ago - 7 years 2 months ago #13 by Tezzating
No eBay APP ID défined in Kunena configurationPorts are done. Would upload pix but the phone won't let me :P

If I can't get a good price on a kinetik then I'm making a trip to various battery places and probing their Optima until I find the one with the highest float voltage.

[edit] adding pix of crappy ports




Also came across this thanks to a dude on thezcr.com


The lazy mans signature (TM)
Its Decibelcar.com Baby

This message has an attachment image.
Please log in or register to see it.

7 years 2 months ago #14 by Tezzating
Picked up a BT G34D. nobs at Walmart were carrying on its the wrong battery *sigh* whatever.
Anyways, this one floats @ 12.78V on the shelf :rock:

Of the 12 Optima's I tested (yes, including the smaller BT 34S, RT G34 & RT G35) this one was the strongest. All the others sat around 12.52V. So if you have a chance, take your DMM and measure the DCV on all the available batteries and get which ever sports the highest voltage float.. that ones usually the newest one so it'll last longer too.

Suppose I'll start work on "training" the battery today. For anyone who's following this and doesnt know what training is:

1. DMM all the batteries you can until you find the one putting out the best idle voltage and grab it.
2. Pop it onto the charger. If you can adjust the output voltage, set it for 15V. Use low current, 1-5A at most.
3. Attach your DMM.. initially the DMM will show lower voltage, usually around 13V.
4. Leave it charging until the DMM shows 14.7-15.0V, then take it off the charger.
5. Leave it resting for 12-24 hours.
6. Repeat.

After a few cycles like this over a week or two, the battery will "learn" that it should maintain a higher state of charge.. so you'll get a nominally higher float voltage.

Whilst on the topic of batteries and street classes.. any Street competitor knows that power is king. You can run all the wires you like, but if the battery doesnt deliver you wont make it. My advice for anyone running an engine-off class:
- Dont DD your SPL battery if possible, you'll degrade its performance.
- If you must DD it, do maintenance charging as often as you can.
- Maintenance charging should be a trickle charge of 5A or less.
- Never store batteries on concrete ! This will kill them in double quick time, store them on blocks of MDF.
- If you come from a very cold climate (Northern USA, Canada, Russia, Southern Australia, NZ), store your SPL battery over winter and use a regular led acid for those months.
- If you must use the battery in winter, get a battery blanket and use it every night. Regular maintenance charge it too. If your climates cold enough youve got a block heater, you need a battery heater blanket too.

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago - 7 years 2 months ago #15 by Tezzating
Just to add.. I went for the Optima for a few reason (even though Odyssey, Kinetik & Stinger were readily available options).
Firstly, they're the cheapest option @ $260 including tax for a G34. Secondly, they support www.DecibelCar.com so I'll support them :)

[edit] BUDGET UPDATE..

Remove RT Battery -$170
Add BT Battery +$260

TOTAL $929

$71 left, which will go into cables and lugs.

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago #16 by Andy
YES!!!

Steve has "the bug" again :P
7 years 2 months ago - 7 years 2 months ago #17 by Tezzating
After 10 hours charge upto 14.7v and a nights rest the batt floated at 13.27v. After 15 minutes on the charge this morning it shot up to 14.8V. :thumbs:

Pulled the amp out last night.. I think I can trim about 4 foot un-neccessary length from both my power cables simply by routing them down the drivers side instead (where the battery is). Also examined the lugs and they need a good clean (wire wheeling).. I think clean lugs + dialectric grease + shorten + 2 more runs + upgraded chassis earthing will also net a good improvement in SPL.

Also examined the sub-cable.. its 8g. Being lazy I didnt trim it to length either.. there's (no joke) 11.5 foot of cable I can chop out. Tested on the DMM, chopping out 11.5 foot = 0.1ohm impedence drop (from 2.3 to 2.2) :O Again, there's power here.
Will also swap the 12g jump cable between coils for an 8g

Moving the sub to the front of the box, plugging the hole in the top and fitting the two aeros tomorrow. Checked the tail lights and garnish area, easily opened up so I'll fit the leaking gaskets and SD these areas on the weekend too.

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago - 7 years 2 months ago #18 by Tezzating
I did some McMaths if anyones interested. Lets say the total actual power output of the Clarion is 1400WRMS, lets get theoretical.

Current wiring for amp = 1344WRMS total from the amp (maximum deliverable from the existing power supply)
After Upgrades = 1387WRMS

Now lets couple this to power losses over the stupidly long speaker cable..

Before chopping & upgrades = 1319WRMS
After chopping & upgrades = 1361WRMS

That means there's 42WRMS lost in the copper.. aka 3.1% total power loss :O

The lazy mans signature (TM)
Its Decibelcar.com Baby
7 years 2 months ago #19 by Dylan
Shouldn't there be more pictures in this thread? :P

Good to see your starting to get serious Steve. Might give me some motivation to do some SPL in mine again.
7 years 2 months ago #20 by Tezzating
Battery is looking good. Working on the body and engine today.. Got a box of dynamat extreme
Pretty late, updates later

The lazy mans signature (TM)
Its Decibelcar.com Baby
Time to create page: 2.150 seconds