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View Full Version : How much power is needed per driver to go to full active for a 250ti ?



wsilva
04-23-2011, 06:58 PM
I am looking at the different options available to upgrade the crossovers on my 250ti's, and going full active is looking like a possibility.

I can use my present Crown amp to run the 14H-1's, what I have no clue to is just how much power is needed to drive the 044ti, the 104H, and the 108H. I have been looking at some great prices for 6 channel home theater type amps, and have seen models with 30 watts per channel upwards. I would think the tweets and mids would not need much, but the 108H I do not know??

Would it be dangerous to pick a amp that has too high a output per channel?

Some of the amps had ratings of 120 or more watts per channel, which is a tad more than the 044ti or 104H require, would it simply be a matter if turning down the level controls for those channels?

For what it would cost to upgrade the stock crossovers with high end caps, it looks like I could invest instead on a nice 4 way active crossover and have all the tuning options active would provide.

Allanvh5150
04-23-2011, 08:15 PM
When you say full active, do you mean to Bi-Amp or do a full 4 way split?

Allan.

wsilva
04-23-2011, 08:25 PM
Full four way split, My present Crown amp would be used for driving the 14H-1's, so I am looking for what would be required to drive each remaining drivers individually.

Robh3606
04-23-2011, 08:55 PM
What active crossover are you planning on using for the voltage drives?? You can't use generic 12 or 24dB networks.

Rob:)

maxwedge
04-23-2011, 09:09 PM
I could be wrong but I don't think that those HT multi channel amps have sensitivity gain adjustments. :dont-know:

I think if I wanted to do something like this I would just bi-amp those.
Edit: But then I don't think I'd be into messing up a classic like the 250Ti and keep them as is.
Anything wrong with them?

rdgrimes
04-24-2011, 05:01 AM
But then I don't think I'd be into messing up a classic like the 250Ti and keep them as is.
Anything wrong with them?
At the very least, I'd try them with 400+ WPC before doing anything more. I'd also question the need for "high-end" caps, any decent quality cap replacement will get you 99% there.

Eaulive
04-24-2011, 07:39 AM
Would it be dangerous to pick a amp that has too high a output per channel?

No, if you have ears and are not too trigger happy :D
Remember to set the correct gain structure


Some of the amps had ratings of 120 or more watts per channel, which is a tad more than the 044ti or 104H require, would it simply be a matter if turning down the level controls for those channels?

Turning down the gain control affects... gain. Not output power capability



For what it would cost to upgrade the stock crossovers with high end caps, it looks like I could invest instead on a nice 4 way active crossover and have all the tuning options active would provide.

You will need a good 2 x 8 processor, or at the very least two 2 x 4 units that can do independent processing and routing (I.E: different settings on channel A and B), plus the amps, that a got couple of k$.
I'm not used to the "audiophool" stuff but are capacitors really THAT expensive :blink::dont-know:

Robh3606
04-24-2011, 08:40 AM
For what it would cost to upgrade the stock crossovers with high end caps, it looks like I could invest instead on a nice 4 way active crossover and have all the tuning options active would provide.

Just use Solens and Charge Couple them. That what I did when I made my L250ti Jubilee clones. They sound just fine. The botique caps will cost you mega bucks.



I think if I wanted to do something like this I would just bi-amp those.


It's not as easy as it sounds. You need to have an active crossover for the lower half on the 108H then you have to redo the upper half of the passive crossover. You would need to use LEAP or another crossover simulator to rework it so it has the same voltage drive as the original network once you remove the other parts. I had to do that on my Jubiless. I built them as biamp only.

Rob:)

maxwedge
04-24-2011, 09:51 AM
I think if I wanted to do something like this I would just bi-amp those.
Edit: But then I don't think I'd be into messing up a classic like the 250Ti and keep them as is.



It's not as easy as it sounds. You need to have an active crossover for the lower half on the 108H then you have to redo the upper half of the passive crossover. You would need to use LEAP or another crossover simulator to rework it so it has the same voltage drive as the original network once you remove the other parts. I had to do that on my Jubiless. I built them as biamp only.

Rob:)

That's why I edited.:p

wsilva
04-24-2011, 11:35 AM
Thanks for the replies guys.

The present Crown amp I am using is 520 watts per channel, and sounds very nice.

I will have to check what it would cost to upgrade the caps on the stock networks, the posts I have read on the board made it sound quite expensive, time for me to make some inquiries and get a actual $$ amount.

Going full active was appealing for the options it would open up, and the fact the gear could be transferred to another system if wanted.

Still curious what amp power rating would be needed to drive the different drivers.

HCSGuy
04-24-2011, 12:42 PM
If you're going to try it, make sure you put a protection capacitor on the tweeter. Other than that, pretty much any amplifier will do, provided this is for normal home use. Between our ears' frequency response and power distribution, I'd say 10w is more than enough for the tweeter, 20w for the midrange, 75w for the mid bass, and whatever you've got for the woofer, though I don't think you'll use the 520w you have. My 2 cents is that while an active quad amped system gives you flexibility you don't have with a passive crossover, you wil lose the sound character and voicing that these speakers are known for.

grumpy
04-25-2011, 07:29 AM
Based on the initial questions, I think you're asking for a world of hurt...

There has been some good advice in 1) updating the crossovers and -maybe- 2) tackling a
hard-enough job in bi-amping if you -really- wanted to dive in and spend a -lot- of time
and money getting yourself further educated and measurement equipment capability and
experience up to speed. Gotta start somewhere, and 4-way active is certainly "doable"
by just buying equipment and turning knobs, but the system will -not- have the finesse of a
professionally well designed and voiced system... no matter the quality of the cabinet and
raw drivers which may be assembled.

I'm really not trying to bust anyone's balls, but there are maybe 10 people in this forum of
thousands that could pull this off well, and most of them have chosen not to...
"give it a ponder" :)

I personally would not use anything less than 75-100w/ch on any of the drivers, ...
were I so inclined, and would leave tubes out during development.

wsilva
04-25-2011, 10:51 AM
Thank you all for the kindly worded nudges to not screw up my 250ti's :)

I need to stop trying to reinvent the wheel, and in this case, a awesome wheel at that.

Looks like it will be a cap upgrade for the 250ti's and a switch to a cleaner amp down the road.