Clamping a Rockville rxd-m3

[inteva6184]

You have an electrical or connection issue then. you shouldnt be dropping anywhere below 14 volts with a 1600 rms amp if you have a 200 amp alt. Either your wiring is completely insufficient or your grounds arent at a good enough location or you need to do the big 3.

You're 100% right it turned out to be a loose power wire. Gotta check my connections every now and then I guess. Interesting that the Rockville didn't have that issue but the cab did.

 

[Jeffdachef 5,000+ posts]

You're 100% right it turned out to be a loose power wire. Gotta check my connections every now and then I guess. Interesting that the Rockville didn't have that issue but the cab did.

rockville is not drawing the same amount of current.

 

[kr15 5,000+ posts]

Ya that CAB should easily make more power, and probably draw 40 or 50 more amps

 

[wew lad 5,000+ posts]

Its not that hard. Your filters should be open and you test with a 50hz tone unless you have a true rms meter. If its not a true rms meter and you test outside of the 50-60hz range its going to be off. Depending on the frequency it could be off a lot. Using the correct and quality gear is important but understanding how to use it is key.

how much do true rms meters cost?

let me know how many people accurately clamp numbers, and how many of those clamped numbers will actually represent how the amp acts?

if it were as easy as you say, wouldnt we see this done more often

tell me how leaving the filters open will tell you anything useful other than instantaneous output. cool to know sure, useful as far as loudness? no. if you're trying to find out how well an amp is doing you're going to have to play a sweep with your box, which still only tells you your instantaneous output. not as useful as just listening to the **** thing and tuning it. talking about sub amps here.

and yes many meters are for ac voltage and amperage. why? they're cheap and have it calibrated to 120vac at ~60hz (you can imagine why). anything outside and further away from that number will be increasingly inaccurate.

bottom line is its nice to know you're close if you do the short steps, but there's a reason why taylorfade tested amps the way he did

 

[dbjunior 10+ year member]

I'm sorry if you thought I was trying to get cea certified numbers this was more a fun little test I understand it's not the most accurate way to do things. This gives me a comparison compared to other amps like I just got the cab up and running so now I know what the differences between that and the Rockville. I do have an oscilloscope and that is how I set my games so I know there is no clipping I didn't use it for any other purpose besides setting the gains though. I also have an amp clamp. Don't they use the same method I did at DB drags?

You stated you didnt know what you where rising to but if you clamped the amperage and measured voltage to get wattage its just simple math to get your reactive load. When you say you have no idea what your reactive was i assumed you just measure voltage and squared it to get wattage being 1ohm is same amperage as voltage. Do you mind sharing voltage and amperage readings?

 

[inteva6184]

You stated you didnt know what you where rising to but if you clamped the amperage and measured voltage to get wattage its just simple math to get your reactive load. When you say you have no idea what your reactive was i assumed you just measure voltage and squared it to get wattage being 1ohm is same amperage as voltage. Do you mind sharing voltage and amperage readings?

I was having a brain fart its been a long time since I did this kind of stuff. The voltage was 38 and the current was 16.1. The cab tested 51 and 21.1.

 

[Jeffdachef 5,000+ posts]

I was having a brain fart its been a long time since I did this kind of stuff. The voltage was 38 and the current was 16.1. The cab tested 51 and 21.1.

Try clamping at different frequencies.

My loudest frequency for my dc 3.5k clamp only cclamped 800 watts. However at a much lower hz i was clamping well above 1750

Box rise changes with every hz.

 

[dbjunior 10+ year member]

I was having a brain fart its been a long time since I did this kind of stuff. The voltage was 38 and the current was 16.1. The cab tested 51 and 21.1.

So the rockville made 611w @ 2.36ohm rated at 750w @2 not bad. The cab made 1076 @ 2.41 still decent and should net a 2db gain.

 

[inteva6184]

Try clamping at different frequencies.
My loudest frequency for my dc 3.5k clamp only cclamped 800 watts. However at a much lower hz i was clamping well above 1750

Box rise changes with every hz.

Thanks for the info. I wont be testing the rockville again but maybe I will try that out with the cab if I get some time.