Pass kits

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I plan on ordering a number of pass kits for my speakers. I am making a 3 way system and want to use a Pass class A on the tweeter. i am crossing them around 6k - AES is 35 watts, program power is 70 watts. I am shooting for clear uncolored sound. Can you please recommend me 3 of the pass mono blocks for this driver?
I am guessing out of the boards available the f5 would be good? These are fantastic drivers - the ACA doesn't have the power I am looking for as I am trying to hit high levels of spl.

For my high mids (2 5.25s highly sensitive) perhaps the turbo - running them at 4 ohms ideally I'd like at least 75-100watts.

The low mids/lows are 10s and again highly sensitive and planning on using lfet ab for them the the subs to get as much power as possible without so much heat. The 15s are not as efficient as the rest. This is for a surround sound set up so while I plan on an f6 and possibly some tube equipment for stereo, transparency is the key.
I can add more woofers. Or I can adjust the gain on the cross over so it is proportional. I am looking to get a min of 124 db spl out of these so I do need more wattage. I am probably going to have to use an AB design for it. Supposedly mixing and matching amps to get the right sound for each driver is a bad idea as they sort of have to be timbre matched like tweeters and multi channel speakers. That being said, can I still bias the tweeter with an A and the mids and low mids ab and have the right character? Or is it best to stay all in 1 class? From what I understand isn't every additional driver add 3 db sensitivity to that set of driver so if nominal is 99 and I'm running 2 isn't 102 the efficiency of the drivers?
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Theoretically yes, another same driver will get you 3db more, but there's box size and room reinforcement to consider as well. Adjustable XOs come in handy here.

I use a three-way active setup. 3 different amp, but all from the same "extended family" so to speak. All class-A. Some single-ended, one is Class-A push-pull for the bottom end since it has more power. 6w for tweeters (4 ohm), 13 watts for the parallel mids (4 ohm) and 50w for the woofer (8 ohm).

I adjust the gain to balance the drives and gain of the amps; using the least efficient driver/amp gain combo as a center point for the other two pairs of amp/speakers.
The setup comes out to being 90db efficient. (No passive components for the drives. Although I may add a series resistor to the tweeters to increase the impedance of the tweeter so it's easier for the SE amp to drive them. It's a 96db semi-horn Vifa.)

Having separate amps for all 3 frequency ranges mostly requires you to adjust the gain so that all speaker's sensitivity match. It's helpful to have same amps, but not required, and who's to say 3 different amps can't sound as good or better. You work with what you have or experiment to find out.

I do think 124db at close range, in any room, is harmful to a person's hearing.
Unless you are using this setup for sound reinforcement, then Pass/FW amps might not be the route to go anyway. High-end audio is a bit of a finesse won't gain anything by brute force. If your room is the size a Costco warehouse, then have at it, but then get some Crown amps instead and be happy.

Good luck!
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I know a lot of power can be dissipated. And the power can to wasted as heat. I was thinking the 30w pass on the tweeter and my topography I been workin on for the others. I may under power it and run a for tweeter. Ab for 5.25 and 10a. Yes it is a new version of active crossover and something I am very pleased with. A friend who I trust dearly and feel he knows what he's talking about said not to mix and match amps. Chip for one most lfet for other pass for the 3rd or something of the ilk so I'll just stay with the lfets I guess.


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I am looking to get a min of :hypno2:124 db :hypno2:spl out of these so I do need more wattage.

In the interest of safety and health, I suggest that this conversation be ceased immediately.

Please see below -

"Sound pressure is measured in decibels (dB). Like a temperature scale, the decibel scale goes below zero. The average person can hear sounds down to about 0 dB, the level of rustling leaves. Some people with very good hearing can hear sounds down to -15 dB. If a sound reaches 85 dB or stronger, it can cause permanent damage to your hearing. The amount of time you listen to a sound affects how much damage it will cause. The quieter the sound, the longer you can listen to it safely. If the sound is very quiet, it will not cause damage even if you listen to it for a very long time; however, exposure to some common sounds can cause permanent damage. With extended exposure, noises that reach a decibel level of 85 can cause permanent damage to the hair cells in the inner ear, leading to hearing loss. Many common sounds may be louder than you think…

  • A typical conversation occurs at 60 dB – not loud enough to cause damage.
  • A bulldozer that is idling (note that this is idling, not actively bulldozing) is loud enough at 85 dB that it can cause permanent damage after only 1 work day (8 hours).

  • When listening to a personal music system with stock earphones at a maximum volume, the sound generated can reach a level of over 100 dBA, loud enough to begin causing permanent damage after just 15 minutes per day!

  • A clap of thunder from a nearby storm :hypno2:(120 dB):hypno2: or a gunshot (140-190 dB, depending on weapon), :hypno2:can both cause immediate damage.:hypno2:"
Hey man, I tried...

"I do think 124db at close range, in any room, is harmful to a person's hearing."

I know you did. I appreciate it also. It's just a special project for special applications - multiple configurations are able with this set up. Once everything is done I will show some pics. I am sincerely hoping that the house will be completed for Cedia this year. Deadline is June. If not I'll show a few things in October and then the house next year. Too much work for one guy and may not finish inside and out
I saw My Bloody Valentine (a band, for those of you who don't know) at reportedly 120db.

It's the only concert I've worn earplugs to (they had warnings posted and crowd control passing them out). I literally thought to myself "If these earplugs fall out I will die" and I had serious concerns that the building would collapse at any time. I've been trained in a earthquake simulator at was a similar level of violence. A good portion of the audience had to leave.

You don't want that. Constant 120+db will steal your soul.
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