DR build questions

For unmatched sensitivity.
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Keryn O'Shea
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Re: DR build questions

#46 Post by Keryn O'Shea »

Until l can measure cabs, can anyone speculate on performance of the DR280 compared to a TLAP?
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Seth
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Re: DR build questions

#47 Post by Seth »

Are those Alpha 8 drivers?
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Keryn O'Shea
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Re: DR build questions

#48 Post by Keryn O'Shea »

Seth wrote: Sun Dec 10, 2023 5:15 pm Are those Alpha 8 drivers?
They are an "Fs" brand, rated at 180w. VFM Audio here used to import their range and they were great, though VFM dropped the speaker side of their operation. I tried to dig up specs.. no luck. I've never thought l needed more midrange with these, one thought was to add 4x compression drivers.. they'd be bolted to the side as there's no room in the cab.
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Seth
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Re: DR build questions

#49 Post by Seth »

They are 8 inch drivers, correct? Not 6 inch drivers
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Keryn O'Shea
Posts: 423
Joined: Sat Jan 26, 2013 5:50 pm
Location: Brisbane, Australia

Re: DR build questions

#50 Post by Keryn O'Shea »

Yes, 8 inch drivers

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Seth
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Re: DR build questions

#51 Post by Seth »

Keryn O'Shea wrote: Sun Dec 10, 2023 4:00 am Until l can measure cabs, can anyone speculate on performance of the DR280 compared to a TLAP?
My speculation is:
DR280 - 131dB at 250 watts
TLAH Pro - 129dB at 1000 watts

Here's how I got there, just mathing them out;
DR280's average sensitivity is 107ish to my eye. The basic recommended driver, Eminence Beta 12, has an RMS power rating of 250W which equates to +24dB. Adding those up gives us a potential output of 131dB.

TLAH Pro's sensitivity is 102dB at 2.83V. But, it's a 4Ω cab. So, just for the sake of easy math I'm going to subtract 3dB from that to give us a 1W/1M figure of 99dB instead of a 2.83V/1M figure of 102dB. The RMS rating of the recommended Alpha 8 driver is 125W, or 1000W for all eight drivers. 1000W is +30dB, bringing the total calculated potential output to 129dB.

The numbers are close enough to loosely say the two cabs essentially have the same peak output potential. But, the DR280 will do it on waaaaay less amplifier.

What amplifier are you using to drive your TLAH Pro's?
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Keryn O'Shea
Posts: 423
Joined: Sat Jan 26, 2013 5:50 pm
Location: Brisbane, Australia

Re: DR build questions

#52 Post by Keryn O'Shea »

Seth wrote: Mon Dec 11, 2023 4:26 pm My speculation is:
DR280 - 131dB at 250 watts
TLAH Pro - 129dB at 1000 watts
Legend! l really appreciate you taking the time for that mate 👍
The Alpha 8s would outperform these drivers l'm assuming... though there's never been any distortion.
I use 2x QSC MX3000a for anything l use outdoors,
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they're beasts, and quite heavy! I hardly lean on them for the tops, whenever l get the shits moving them around and look to replace them, l see the price of lighter quality amps with the same output.. then just close the laptop and walk away!
With your calculations, l may be able to leave one at home with the DRs, & use something lighter. I guess that's the aim with horns, yea?

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AntonZ
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Re: DR build questions

#53 Post by AntonZ »

Keryn O'Shea wrote: Tue Dec 12, 2023 3:02 am With your calculations, l may be able to leave one at home with the DRs, & use something lighter. I guess that's the aim with horns, yea?
I think that is right indeed Keryn. Your back will thank you by lasting a bit longer.

I have never heard TLAP. However I have owned a single DR250 for a while. Even though it was an older style and had only part of the recommended number of piezo tweeters (it was built for use with bass guitar), it still is to this day just about the sweetest sounding cab I have ever had the pleasure of playing music on. The piezo's were old style cross firing. No melded arrays. Really just two or three round piezo's per side, one mounted right above the other. Simply bloody marvelous with decent EQ, I kid you not.

And it played STUPID loud, with very little power. Did I just say STUPID loud? Make that FREAKING STUPID LOUD, if you will. Only once have I attempted to drive it hard, with one side of a 60W/channel home amp. Not even pro gear. I just could not get myself to run it full tilt. That crazy thing made every single hair on my body stand up. I had to turn it down for the sake of my sanity, I did not get to run it at it's full potential. I have played in bands before the age of in ear monitoring and sensible stage levels, so it is not that I have never been exposed to loud music. This was next level. And then some. Now for the most amazing part in my humble opinion: every other system that I have heard while driven hard sounded harsh. When driven hard this cab was every bit as sweet as it was at sensible living room volume. And STUPID LOUD.

That last bit seems to align well with the calculations from Seth. I did think it would be like that. But I just did not have the output figures and math available to make it that far. Thanks for confirming my suspicions, Seth.

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Re: DR build questions

#54 Post by Seth »

Keryn O'Shea wrote: Tue Dec 12, 2023 3:02 am ...Legend! l really appreciate you taking the time for that mate 👍...
:thumbsup: No problem. Honestly, it's basic audio math I feel we should all know. One of these days, I'll type up an audio math post and see if I can get it put in the FAQ section.
...I use 2x QSC MX3000a for anything l use outdoors, they're beasts, and quite heavy!... ...l may be able to leave one at home with the DRs, & use something lighter...
Awesome amps! They are, indeed, beasts. Weight and output specs.

I'm always intrigued with amplifiers that have more than two channels, especially in a 1RU package. The amps I have and use now are 8 channel in a 2RU chassis and I love them. But, there are more and more 4 channel amps in a 1RU format coming out with ungodly power ratings. Most notable are the offerings from Powersoft, which also come with an ungodly price tag. But, there are some off-brand offerings hitting the market from brand names I've never heard of, like Admark and even more affordably priced amps from Sound Town.

In my web surfing and research, the Admark amps reportedly have relatively trustworthy specs and have been deemed reliable in some circles. But, I'd love to test and have some of the Sound Town amps prove relatively accurate and reliable too. It would be sweet to have something like the the 4 channel, 480W "RMS", 1RU amplifier they offer be a valid workhorse. If the ratings are relatively accurate, it would be able to power your whole DR280/T48 system in 1/6th the rack space your current amps occupy and for only $300 USD . However, a quick search leads me to believe it would cost you more than double that to get one in Australia. So, yeah... I get what you're saying about giving up on shopping. Too damned expensive! Might be cheaper to hire a youngster to tote your beast amps around! LOL


AntonZ wrote: Tue Dec 12, 2023 11:50 am ...Thanks for confirming my suspicions, Seth.
:thumbsup: You're welcome. Any time, Anton.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Keryn O'Shea
Posts: 423
Joined: Sat Jan 26, 2013 5:50 pm
Location: Brisbane, Australia

Re: DR build questions

#55 Post by Keryn O'Shea »

AntonZ wrote: Tue Dec 12, 2023 11:50 am ..it still is to this day just about the sweetest sounding cab I have ever had the pleasure of playing music on..
That's certainly something to look forward too, had a good chuckle reading your post too mate
Seth wrote: Wed Dec 13, 2023 4:45 pm Honestly, it's basic audio math I feel we should all know..
I also look forward to when l can educate myself properly, until then l will pester you guys!
Seth wrote: Wed Dec 13, 2023 4:45 pm ..it would be able to power your whole DR280/T48 system in 1/6th the rack space your current amps occupy..
😯 definitely worth looking into, thank you
Seth wrote: Wed Dec 13, 2023 4:45 pm Might be cheaper to hire a youngster to tote your beast amps around! LOL
I'll look at building them into a frame with handles so l can move them around with a trolley over Christmas, the brakes on castor wheels aren't strong enough to stop them sliding around in the van

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Re: DR build questions

#56 Post by Seth »

Keryn O'Shea wrote: Thu Dec 14, 2023 1:33 am I'll look at building them into a frame with handles so l can move them around with a trolley over Christmas, the brakes on castor wheels aren't strong enough to stop them sliding around in the van
I look forward to seeing what you come up with :thumbsup:
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

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Seth
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Re: DR build questions

#57 Post by Seth »

Odd timing, given we were just talking about it. I just received an email indicating one of the inexpensive four channel Sound Town amps became available as a used/open box item on Amazon. At 45% off, I went ahead and scooped it up.
This one. Looking forward to seeing what it's all about. It claims 4x 800W RMS at 8Ω. I'm not holding my breath. But, I am crossing my fingers. Either way, it's more power than I need for anything. I'll start a dedicated thread and keep you guys posted. Likely wont be until March though.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Keryn O'Shea
Posts: 423
Joined: Sat Jan 26, 2013 5:50 pm
Location: Brisbane, Australia

Re: DR build questions

#58 Post by Keryn O'Shea »

Seth wrote: Fri Dec 15, 2023 1:15 am ..I went ahead and scooped it up.
Wicked man!
Hey this contour gauge allowed me to make just one cut with the side braces, the pencil method wasn't working for me as the bendy ply l had to use on cab one wasn't the greatest & it's come in handy with a few other cuts too.
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Keryn O'Shea
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Location: Brisbane, Australia

Re: DR build questions

#59 Post by Keryn O'Shea »

That's me out of build time for this year..
All the best to you good people, have a safe holiday pondering your builds for next year, cheers 🍻
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The J10Lite would be a sweet cab to build after these..

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AntonZ
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Re: DR build questions

#60 Post by AntonZ »

Same to you Keryn!
Keryn O'Shea wrote: Thu Dec 21, 2023 11:00 pmThe J10Lite would be a sweet cab to build after these..
I reckon they'd be easy sailing after a pair of DR's.

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