Hey ya guys, i've got a question, can the amount of headroom a dj mixer has make a difference to the overall spl you can get out of your sound system? The reason I ask is because my old system seemed louder than my current system. My old system was two Peavey Hi-Sys 4XT mid/highs (power : 700 watts continuous each/sensitivity : 100db), four JBL MP418S (power : 650 watts continuous each/sensitivity : 101db), the mid/highs were powered by a QSC RMX2450, one cab per channel giving each cab 650 watts average power, a QSC PLX3002 powering my subs, two subs per channel giving each sub 750 watts average power. I also had a Behringer CX2310 crossover and finally a Vestax PMC05 dj mixer, specs here :
• Inputs: Phono x 2 (RCA), Line x 2 (RCA), Mic x 2 (1/4 inch)
• Output: Line x 2 (RCA), Phones x 1 (1/4 inch stereo)
• RMS Output: -7dBm
• Freq. Response: 25-25KHZ + 1.5dB THD: 0.02%
• Cross talk: more than 70dB @ 1KHz
• S/N Ratio: more than 75dB
• Input Impedance: Phono/56K, Line/10K, Mic/3.3K (ORMS)
• Output Impedance: Line/2K, Phono/8K
Now i'm using two Peavey UL215H mid/highs (Power : 1,000 watts continuous/sensitivity : 100db) which are the newer versions of the old Hi-Sys 4XT cabs but other than that are nearly identical and i'm powering them with a JBL MPX1200 amp, one cab per channel giving each cab 1,200 watts average power. I'm using two JBL SRX728S subs (power : 1,600 watts continuous/ sensitivity : 98db) powered by two bridged JBL MPA750 (re-badged QSC EX2500) amps, one amp bridged per sub, giving each sub 2,000 watts average power. I'm using a Dbx Driverack PA and finally a Stanton SA.3 dj mixer, specs here :
Line inputs: 2 (RCA) x 2 channels, -10 dBV /10 kOhm
Phono inputs: 2 (RCA) x 2 channels, -50 dBV / 47 kOhm
Master output: 2 (TRS Balanced/RCA unbalanced),
+4 dBu balanced / -10 dBV unbalanced
Headphone output: 1 (1/4 inch), 1 (1/8 inch), greater than 32 Ohm load
Frequency Response: 20 Hz - 20 kHz, +/- 1.5 dB
Tone Control : Hi +9/-18 dB
Mid +9/-25 dB
Low +9/-25 dB
S/N Ratio: Better than 94 dB (ref: max input level)
Noise: -80 dBV (Line input to any output)
T.H.D Less than 0.04% (1 kHz)
The Stanton mixer seems to clip a lot quicker than the old Vestax mixer I was using. The Vestax mixer's red lights were at +6dbv on the mixer's vu meters and the Stanton's red lights are at only +2dbv on it's vu meters. Does this mean that the Vestax has (roughly) 4dbv more headroom? The sound, well I mean spl, doesn't seem to be as loud on my current system using the Stanton dj mixer as it did on my old system when using the Vestax, but i'm using more power now with my current sound system than I was using with my older system. Gain structure was set back then with my old system and i'm setting it now with my newer system.
