Has anyone built GC into a speaker to make a self powered monitor?

[ronc]

The easy way out is just a good pre amp. I am using a TDA1524a kit with 12 batt supply which is intergrated into the amp case but it will help with the added distance of a pre to the amps (being mounted on or in,not reccomended,of the speakers).The difference with my pre is i install trim pots on the balance,bass ,trebel and taylor the countour slope with another trim pot(my horns need a little help at low volumes).The only knobs on the amp face is the volume and the selector knobs, i leave it on 24/7.The reason i chose the TDA1524a chip is the fact that the pots are not in the signal path.With battery power on the pre and the amps ,IGC LM3875T,the sound is exceptional driving my fostex FE103e horns.
ron

[tbla]

Am I missing something?

yes, the sound depends on implementation - those "commercial things" don't deliver high class sound.....

[Peter Daniel]

Originally posted by e.lectronick




Wow.
That's some pretty hardcore engineering. None of that was necessary for the Alesis.

Is all the isolation necessary because of the Gainclone's sensitivity to vibration in particular? Or is any amp going to be this way?

It begs the question how did Alesis achieve a working amplifier as depicted in JCoffey's post -second from the top?

I had envisioned a high output current balanced preamp or a distribution amplifier as the device which would drive the line to the powered monitor. That would be consistent with a pro studio setup.

It all depends on what you are expecting from the amp. You can attach the chip to woofer's magnet or basket (pretty smart as heatsinging problems are gone), and it would work, but performance wouldn't be probably nothing to wright home about.

Now, I'm talking about kind of performance that rivals most any amp on the market (in it's class) and this would be hardly achieved if amp is integrated in a speaker. Whatever Alesis did, doesn't even come close to what can be achieved.

[ronc]

If you want to see clutter in a signal path , just look at most commercial amps.
At first i was very doubtful about the "buffered" GC, but i have to admit that the active pre chip sounds better than my inactive pre which was a shunted 50K alps pot.
I am really waiting for a report on a batt powered tube buffer before i try that avenue.
ron

[fezz]

correct me if i am wrong but:

i think that it would be better to have the amplifer as close to the course as possable, as a low power, low voltage signal sould degrade more then an amplifed signal going to the speakers

therefore it would be better to try and get the signal path BEFORE it is amplfied as short as possable for a better quality of signal - this would require all the amplifers to be in one box attached very closly to the source

[Circlotron]

Originally posted by e.lectronick
*snip* And there's the benefit of being able to tweak the amp and speaker response together so they are matched well. Some kind of built in eq filters perhaps to account for any dips or peaks in signal response of the driver in that particular enclosure.

[JoeBob]

I use a somewhat GC to power my "active" speakers. I couldn't do it any other way, for my girlfriend always complained that all my amps and preamps were to ugly (I found them nice, she just thinks stereos are stupid) so I moved the amps into the speakers. Also the amps have built in filters that account for the dipole rolloff and there is motion feedback from the woofer which I would have rather not run all the way to the amp in a chasis far away. For me it worked out very well, when building an amp in a speaker you have lots of room to layout things exactly how you want it, can omit any insulation between the transistors and the heatsink (I use dipoles, with wings, so it doesn't heat up a box, and I have material over the open sides to keep out cats and fingers, so there's no zapping), there are advantages and disadvantages, weigh which are important to you. I very much like my active speakers now, yet they're constantly improving...

[Da5id4Vz]

You can attach the chip to woofer's magnet or basket (pretty smart as heatsinging problems are gone), and it would work,

JBL built some kind of cool and often imitated PA cabinets that weren’t too far off the mark from this. To optimize construction efficiency, the LF spider, heat sinks, and large portions of the cabinet were cast out of a large piece of aluminum alloy. They had the casting on display at some trade show a few years back. It was quite impressive. I had to stare at it a long time to completely comprehend what I was looking at. These were for PA cabinets, I haven’t heard of anyone using a set in the living room.

e.lectronick,
Have you looked at (or listened to) the Genelec 1031A and Meyer HD-1's?

[e.lectronick]

Originally posted by Da5id4Vz
e.lectronick,
Have you looked at (or listened to) the Genelec 1031A and Meyer HD-1's?

I have listened to the Genelecs. They had them at Sear Sound in NYC where I interned many years ago. Very nice sound. Loud, punchy, tight and clear. They had incredible detail. I haven't heard the Meyers however.

With successful active nearfields like the Genelec and others, I know there are ways to make the idea work as a homebrew project. It might even be worthwhile to build them and sell them on Ebay or something as custom alternatives to the super expensive high end monitors being sold by those companies.

-Erik.

[Da5id4Vz]

The HD-1's sound a lot like the Genelec's, very good. They do however sound different. I found that material mastered on one doesn’t necessarily find the sweet spot of the other.

I remember exploring the insides of both. The Genelec has defiantly got a bunch of chip amps in it. It must have been too early in the morning, too long ago when I explored the HD-1. I can’t remember anything about the insides.

I do remember that I loved them both, and dream of having some for my home.

-Dave