Amplifier power for THT

For livingroom sound better than in a theatre.
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cerescobra
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Amplifier power for THT

#1 Post by cerescobra »

I'm finally finishing my home theater that I've been planning for over 10 years. And ten years ago I built a pair of 24" THTs with Dayton RSS390HF-4 drivers. Now that I'm stuffing equipment in the rack, I'd like opinions on what amplifier power to use. I have the choice of 200 or 550 WPC into 4 ohms from two Sherbourn amps. I generally go bigger, but don't want to damage the drivers in the THTs if 550 is too much for them. But I don't imagine ever putting anywhere near the full 550 W to them. Is that an issue if I use my ears to control the loudness? I'm confident I know how much is too much when it comes to bass.

Thanks for your inputs and shared experience. I'm getting really excited to hook them up and enjoy them!
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Bruce Weldy
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Re: Amplifier power for THT

#2 Post by Bruce Weldy »

cerescobra wrote: Thu Feb 24, 2022 5:05 pm Is that an issue if I use my ears to control the loudness? I'm confident I know how much is too much when it comes to bass.

Thanks for your inputs and shared experience. I'm getting really excited to hook them up and enjoy them!
Yep, it's an issue. With horns, you won't hear the harmonic distortion that would tell you to turn them down. If you are going with a high wattage amp, you'll have to get a limiter like a DBX driverack. I'm not sure of the limit on those drivers, but I'm sure 500 watts (approx 44 volts) would probably be the top end for that driver. It's not listed in the plans.

Personally, I'd go with the 200 watt amp to be safe. That should still be much more than you'll ever use in a home theater.

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hotbutta
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Re: Amplifier power for THT

#3 Post by hotbutta »

Get the 550's. More smiling, less clipping.

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Bill Fitzmaurice
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Re: Amplifier power for THT

#4 Post by Bill Fitzmaurice »

I can't imagine ever giving them even 100 watts each, so 200 WPC is plenty.

hotbutta
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Re: Amplifier power for THT

#5 Post by hotbutta »

Hehe, we got Bill to say the W-word. I guess Appo1999 and I are the few who throw 50 volts at our THT's.

Rich4349
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Re: Amplifier power for THT

#6 Post by Rich4349 »

I can't imagine having the need or enough pre-existing hearing loss to give THTs enough volts to kill them (indoors, where they're supposed to live.)
2 DR250s, 2 27" Lab15 T-60s, 2 30" Neo Titan 39s, 1 Autotuba...and looking for more!

cerescobra
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Re: Amplifier power for THT

#7 Post by cerescobra »

I've taken Bill's recommendation. They're getting 200 WPC @ 4 ohms and sounding great. Thanks for the responses!

cerescobra
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Re: Amplifier power for THT

#8 Post by cerescobra »

So yesterday my neighbor helped me lift the 50 lb. beast of a projector onto its ceiling mount. I got it hooked up and adjusted image location on the screen. Then I decided to check various Blurays with different aspect ratios to see how they appeared on the screen and made some minor tweaks. Then I discovered that I had no center channel audio and found that I hadn't connected the XLR cable from the XMC-2 to the amp. Whoa, did that make a difference?

My friends have asked me what would be the first movie I'd watch when the theater was done. Well, it wasn't a movie. The last aspect ratio I checked was 16x9 and happened to be with the Bluray of the Eagles Farewell Tour Live from Melbourne. And I thought it might be good to sample the audio since I had just added the center channel to the mix. Well, I sampled nearly the entire concert. The projector throws a spectacular image, but the audio was unbelievable. With DTS-HD Master Audio 5.1, I've never heard a more realistic concert audio track or one that is as percussion-forward as this. The 40+ year old Klipsch Heritage speakers performed beautifully and the capability of the Tuba HT DIY subwoofers was more than confirmed. Tight, punchy bass was fabulous. And all I've done in audio setup was to set speaker distances. I haven't gotten the dB meter out yet to set levels and haven't even thought about setting up Dirac. Or experienced a movie with a Dolby Atmos soundtrack. And none of the room treatments have been added. So this is going to be a really fun journey!

I still have lots of finishing to do in the theater and I'll look forward to very high quality work tunes along the way. Still haven't decided on a first movie yet.....
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Tom Smit
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Re: Amplifier power for THT

#9 Post by Tom Smit »

If there was a "like" button, I would have hit it.
TomS

cerescobra
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Re: Amplifier power for THT

#10 Post by cerescobra »

Thanks Tom!

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Bill Fitzmaurice
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Re: Amplifier power for THT

#11 Post by Bill Fitzmaurice »

You may find the surrounds a bit too locatable. If that's the case placing diffusors in front of them would help. Something like this, which isn't difficult to DIY.
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cerescobra
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Re: Amplifier power for THT

#12 Post by cerescobra »

Thanks for the advice Bill. So far I haven't noticed that being a problem, but haven't dialed in the system yet.

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