thoughts on head room?

Glen

I have now read as much as I can ingest in the new member section and have a quiet, hiss free punchy system per drive rack gain structure and recommended cross over points for my small DJ style system..

Set up is two way

Mackie 1402-VLZ board

Drive Rack PA

31 band stereo EQ

4-SR4732X 3 way cabs two 12\"drivers one 2447 compression driver and 2404 UHF driver all rated 1200 to 2400 w @ 4 ohms I run passive with Two -Power Teck- 3 Crowns 760 per side at 4 ohms run in stereo

2-SR4715 base bins rated 1200 to 2400 w at 4 ohms One Micro Teck 2400 800 per side at 4 ohms in stereo

2-MP255S base bins One Macro Teck 2400 in stereo\" use as side fills with EV monitors.

I ran this system out doors and have zero head room I never clipped anything just pulled low frequencies started flat and have a few dbls up or down a pretty straight curve on 31 band EQs.smile curve sounds the best but not when shes running beyond a few leds on my board bottom end is weak.. It just isn't cutting the mustard.

I have tried to by amp my JBL srx4732s by removing rear cover changing input mode connectors then running crown power Teck 3.1 on highs and Macroteck 2400 on lows and 4715 cabs as sub with another Macro Teck 2400 per Drive rack 3 way set up and it sounds like a transistor radio.
Running two way Full range with 3.1 amps passive on tops and 2400 on subs sounds very good and tight up to 20 or 30 ft.

Should I be looking for a pair of powered Vortec 4888 or 4889 DP tops and 4880dp powered bottoms and use the above set up as side fills to get serious punch and head room?

Or maybe put my Crown 2400s on 4732s and throw a couple Macro Teck 3600s on two pair of JBL SRX 728s twin dual 18\" 1600 watt 2241 driver cabs for subs. Just want more punch than I can use when I run in doors and adequate punch out doors.

Thanks in advance for your time and any suggestions other than that I'm way over my head, as I already know that.
Glen

Dennis

Please explain: \"I have tried to by amp my JBL srx4732s by removing rear cover changing input mode connectors\".

Is there not a Biamp/Passive switch on the JBL SR connector plate?

\"Should I be looking for a pair of powered Vortec 4888 or 4889 DP tops and 4880dp powered bottoms\"

One or two Vertec per side will make for a pretty short line array.

Dennis

Glen

Dennis wrote:

Please explain: "I have tried to by amp my JBL srx4732s by removing rear cover changing input mode connectors".

Is there not a Biamp/Passive switch on the JBL SR connector plate?

"Should I be looking for a pair of powered Vortec 4888 or 4889 DP tops and 4880dp powered bottoms"

One or two Vertec per side will make for a pretty short line array.

Dennis

Thanks Dennis,
I changed input selector to bi amp inside the 4732 input pannel then went by Drive rack 3 way set up for highs mids and sub ..

There is a foot note with these JBL cab specs that says SRx loud speakers may be operated in bi amped mode all crossover components are bypassed (except in the case of the 3- way 4732x and 4735 cabs)the voice coils of the drivers are connected directly to the power amp outputs.When operated in this manner,an external,electronic crossover is required.Such crossovers may be installed in power amps or be separate processors.
I assume because Drive Rack has this set up programed that I was good.I am also using the same two pin Speakons to bi amp as I do for full range could that be my problem as well?
Thanks!

Dra

X-over points recommended by who? The wizard?
Also, you have 4 sub drivers trying to keep up with 8 lo-mid drivers. To do what you want, you need (at least) 8 sub drivers if not 12 or 16.

DRA

Glen

Dra wrote:

X-over points recommended by who? The wizard?
Also, you have 4 sub drivers trying to keep up with 8 lo-mid drivers. To do what you want, you need (at least) 8 sub drivers if not 12 or 16.

DRA

Dra,
Yes I used the Wizard and cant remember at this time where they had me crossed over .

Top 4732 cabs JBL rating HF (2) 150 to 300W @ 16ohms and LF (3)/ Discrete (4) 1200 to 2400 @4 ohms specs
39Hz-21kHz
jbl cross over points 1.2kHz,6kHz

In full range the 12s chest punch with no honk or distortion way better than my subs.

4715 dual 15" subs are rated 35Hz -300 cross over 80-100Hz .Subs can only handle upper bottom and low mids they are very close to my 12s in the top cabs.
thanks

Dra

As is, I think I'd set a HPF at 45hz and LPF at 90hz. If the 12's peform as well (in relation to the subs) as you say then, maybe going as low as 75hz, since you have so many of them.
Dennis?

DRA

Glen

Dra wrote:

As is, I think I'd set a HPF at 45hz and LPF at 90hz. If the 12's peform as well (in relation to the subs) as you say then, maybe going as low as 75hz, since you have so many of them.
Dennis?

DRA

Thanks Dra ,
I will give it a shot this evening with bi amping again at your recommended points.
And mean while should I be looking for two pair of double loaded 4719s or the newer SRX 728s 18" cabs to help fill my void?
I am not apposed to any speaker manufacturer I could care less if it says JBL ,PV or what ever I just want clean sound.
And if so with 18s vs 15s
Is there a way of incorperating the pair of 4715s in this mix as they are clean just not sub bass, as the 18s will most defiantly cross over lower?
thanks!

Dennis

On all of my SR-A configurations, I have been crossing the subs at 80Hz (even though everyone says not to). I will get into my settings in detail at lunch or after work today.

Dennis

Dra

You mentioned 728's. Do you have these?

Glen

Dra wrote:

You mentioned 728's. Do you have these?

I dont own any 18" cabs yet!

I have a pair of jbl 4715s and a pair of inverted 15 jbl sub mp255 cabs 500 watt contious and 2000 peak fr res 38Hz-160Hz

I was using all 4 sub cabs together but the system sounds much better without the 255s in the mix which are crossed over the same as the 4715s.

I have to change eq so much as both sets are run stereo from Drive rack each with a 2400 crown.

The 255s make good monitor side mix's with its own separate eq.

Glen

Dennis wrote:

On all of my SR-A configurations, I have been crossing the subs at 80Hz (even though everyone says not to). I will get into my settings in detail at lunch or after work today.

Dennis

Thanks Dennis!

Dennis

Hi Glen

I have some settings that I have worked out for SR4732A and SR4719A on a BSS Omnidrive. I have tested these settings live and they work out well. I found that settings don't track perfectly from an Omnidrive to my Driverack 260 and I had to make slight changes. The changes look correct on my SMAART program but I haven't tested the changes live yet. So, give this a try:

SUB Hi-pass 30.4Hz BW18
Lo-pass 81.1Hz LR24
Delay 0.23ms
Output level +2dB

MID Hi-pass 81.1Hz LR24
Lo-Pass 943.9Hz BW24
Delay 2.35ms
Output level -2.8dB

HIGH Hi-pass 943.9Hz BW24
Lo-pass OUT BS6
Delay 2.15ms
Output level +1dB

I'm not going to share any EQ settings until I test them. The settings for my dual 18 subs will vary some for your dual 15 subs...Go with Dra's hi-pass frequency and experiment with the crossover frequency. This set up will want to see about 1800W@ 4 Ohms for the subs and for the mids as well, and 450W @ 8 Ohms for the highs. This is assuming that you are running a separate amp channel for each box/passband. All of the output levels are approximate because I am underpowered in some areas and your amp size will be different than mine. Some people will question delay being set on every output. I align my subs at each gig and I leave myself a little wiggle room to add OR subtract delay on the sub outputs. And to answer an earlier question, you will need speaker cable with 4 conductors for the 4732s (highs and mids).

Dennis

Gadget

Eloquent as always Dennis! I concur, and have just been \"lurking\" like most here... enjoying the dialog...you guys ROCK!

BTW the 4719's are hogs compared to the 728's...When you get a chance to use properly implemented Neo~ speakers you will find FAR superior definition ... especially in the mids and hi's...NEO ROCKS :twisted:
g

Glen

Thanks guy's so much for your time and hands on help it's much appreciated, reading archived threads for the last few weeks has also helped tremendously.

I am a musician, a sound man's worse night mear and up in till a month or so ago had zero working knowledge of any of these electronics.

This system was originally purchased new in 04 for my home studio.
It was set up and dialed in by a buddy of mine from a PA based sound company based on my needs at the time.

So I appreciate your patience with my true lack of audio knowledge other than what I have read in the past month.


Do I follow positive and neg from my bananas side to Speakon plug and change pin locations for hi and mid top cabs?


I am now quite certain that it is my pin locations on my bannaa to Speakon cables that makes her sound like a transistor radio when I attempt to bi amp top cabs.
Once I figure out the cable deal I look forward to trying these new settings.
Thanks again guy's I will continue to lurk and learn!
Glen

Dennis

I might just be missing it, but I cannot find SR4700X info on the JBL website. I think the speaker pinout should be:

PIN 1- Mid negative
PIN 1+ Mid positive
PIN 2- High negative
PIN 2+ High positive

When Biamping 4732s, you no longer have the option of looping through the sub to power them.

Dennis

Gadget

Speaker connectors were developed to make more secure connections and better transfer the power of pro audio amp output....Banana plugs (which I do not like) and 1/4\" jacks cannot come close to transferring the hi power of todays amps, that speakons do. Plus they won't just pop out if someone trips on the cables...

That said, I would suggest if your amps are not equipped with speakon connectors, that you hard wire the connections to the binding posts, and add a female connector at the rack and the cables then would be 2 male NL4's...

But in the interest of moving this along, speakons are wired:

Low end 1+ and 1-
Hi end 2+ and 2-

If you were running mono (looks like you are not?) you would then wire the 1+, 1- to the two RED output terminals of the sub amp being careful to hook 1+ to the + red terminal... usually the channel 1, or A...of the amp

If stereo, then I would suggest
1+, 1- to the 1, or A channel output posts/Banana jacks
2+, 2- to the 2, or B channel ...
Feed the hi outs of the Driverack into the 1/A input
feed the low outs (if 2x3, or 2x4 that would be the lo outs (lo left mono if 2x3) of the DRPA...be sure to keep polarity throughout...

Subs would typically just use 1+, and 1- ..

Gadget

Dennis

\"Subs would typically just use 1+, and 1- .. \"

Except that JBL, in their infinite wisdom made their SR subs 2+/-.....

Dennis

Dra

When \"looping\" thru to the sub (or sending speaker level input) does the input \"eat\" the power or just extract what it needs. In other words, does it affect the available power to the \"pass-thru\" speaker?

DRA

Glen

Dennis wrote:

I might just be missing it, but I cannot find SR4700X info on the JBL website. I think the speaker pinout should be:

PIN 1- Mid negative
PIN 1+ Mid positive
PIN 2- High negative
PIN 2+ High positive

When Biamping 4732s, you no longer have the option of looping through the sub to power them.

Dennis

Dennis,
We are running sr4732x 3 way tops in stereo 2- Crown Power Teck 3.1s and 4715 bottoms in Stereo with 2- Crown Macro Teck 2400s.I will have to use a side of one of my 3.1s for highs and mids for testing pupososes and then get a pair of smaller amps for highs when I figure this out..
I will reconfigure my pin locations on speakons and try bi amping once again with your settings.Can I hook up one side only off drive rack and not effect anything just to be sure I have it right?
Thanks!

Dennis

Dra

No, In SRs the speaker cable hits the sub first and then loops thru to the Mid/Hi. There is no network that the \"signal\" passes through...it loops right at the connector panel on the sub.

Dennis

Dra

If you have any concerns or doubts, at all... turn off the low amp and make all the connections, then with the hi amp only on make the connection to the speaker. If you hear the highs from the horn and mid driver (I'll assume that your 3-way cab bi-amps only, correct?) you are good. If you hear highs from the low driver, then you're backwards (and you want have to replace the horn diaphram :roll: ).

DRA

Dra

Dennis, :oops: :oops: :oops:
I thought it was another thread.
:oops: :oops: :oops:
Actually, the thread I was thinking about is on another forum. It dealt with a guy that wants to add a single powered Yorkville sub that can accept line or speaker level input. Someone suggested (or asked about) jumping off the back of the passive top that he intended to continue to run full range.

Now! Does my question make sense?

DRA

Dennis

Dra, Yes it makes more sense...you had better warn him about overlap!!

Glen, testing with one side only is OK. All of your amps are underpowered for your application. The PowerTech 3.1 is only slightly larger than necessary for the horn (one amp channel per horn)...you need larger amps for the 12\".

Dennis

Dra

:evil:
You're not going to answer the question?

DRA

Dennis

Oh! sorry, I don't know the answer off the top of my head. I am about to drive 25 mi to work... can you post the models involved and I will try to answer at lunch. Assuming I get a lunch break at all.

Dennis

Dra

All the Unity, Elite, and NX lines powered subs (U...P), (LS...P), (NX...) have a button (switch) to select line or spreaker input. Got to be a huge increase in impedence, wouldn't you think?

DRA

Dennis

Dra

The Unity manual indicates the speaker level loop thru thing works just fine.

Dennis