festival speaker?

[lars_rooster]

hi im thinking off making a speaker for festival use.
i have read about the SONIC IMPACT T-AMP and would like to use it with this box
http://www.thansen.dk/product.asp?c=...&pn=1220481800

will that be posible??
i would use a 12V car battery for power suply

what about the the "41Hz amp32-PS" is that better for this type of speaker.

i dont know much about hifi. hope you will help.

thanks lars

[Saturnus]

Hi there.

Yeah, that'd work great. I suggest the 41hz amp6-basic though since it's easier to solder. It also is less critical with voltage than the t-amp. Same price too, actually.

Knowing from experience, since I lugged this one:



to Roskilde Festival last year with a t-amp installed in it. I had 2x 12 volts 7Ah SLAs inside, and they lasted roughly 40 hours at extremely high volume.

Some of my idiot friends fried my t-amp though by putting it up for recharge without disconnecting the amp first. So I'd suggest going with the amp6-basic, just as I am this year.

Btw, I have improved the monster by adding some solar panels and a slight redesign.

Anyways, see you at Roskilde. Cheers.

[lars_rooster]

hi

so it's no problem that tha box is a bass box??

i will go for the amp6 then....but will i need 24V then??

Takker

roskilde rocks.....

[Saturnus]

No no, amp6-basic is practically identical to both the t-amp and the amp3s. The only difference is the type of housing for the chip. So all 3 types runs on the same base voltage, around 12 volts.

T-amp and the amp3s use almost exclusively SMD (surface mount devices) and if you're not experienced in soldering those, I strongly suggest you get the amp6-basic (or buy a t-amp off course).

They all have the same voltage rating, except that because of the different housings, the amp3s take a little higher maximum voltage than the t-amp, and the amp6s take a little more than the amp3s.

See the problem is that a fully charged car, or SLA (sealed lead acid), battery has an output voltage of about 13.8 volts, which is higher than the recommended maximum voltage of the t-amp. Another problem is that a common car battery charger can output up to 14.4 volts when charging. This is (slightly) above the maximum rating of the amp3s, and certainly enough to fry a t-amp.

The amp6-basic can take up to 16 volts, though the recommended maximum voltage is 14.6 volts. This means you'll have more headroom.

In any case, if you do connect a charger, make sure it's an electronically controlled one. Don't just go for the cheapest one, as they are likely to just being a transformer with a rectifier bridge, and they'll likely fry even the amp6s.

If you buy a t-amp, I strongly suggest adding a diode from the battery to get a 0.6 volts voltage drop (and protection from reverse voltage). Also make aboslute sure you cannot charge and play at the same time, at all. Trust me, when people are drunk and stoned they'll try anything stupid, no matter how many times you tell them to do it one specific way.

That's also the problem with car batteries and festivals. Car batteries cannot under any circumstances be turned on it's side, or flipped upside down. The acid will pour out, and likely ruin your speaker, and/or clothes, whatever. That's why I strongly suggest you get SLAs. They can be turned any way you like, though it's recommendable that standing correctly while charging.

On a final note, I'd like to point out that those aren't really "bassboxes", they got a tweeter so they should be full range, just don't expect super high quality sound or sound pressure from such cheap speakers.

Good luck. And don't hesistate to ask more questions. Cheers.

[lars_rooster]

bought the amp6-basic.
next step building.....

thanks again!!

[v-bro]

Good choice!

You sure didn't miss a detail Saturnus! Indeed a diode or rectifier bridge can drop the voltage just enough to run a T-amp safely.

I built AMP32 and AMP9, right now busy with a Truepath. I have never been disappointed with 41hz quality. Impossible to beat the bang for the buck...

[Saturnus]

Originally posted by v-bro
You sure didn't miss a detail Saturnus!

Making festival speakers are my pet peevee. I've built a new one every year for 9 years straight. I love to see the jaw dropping effect those have. This year, it's possible to run it the whole festival (8 days) provided we get some sunshine because of the solar panels.

I am though already planning next years completely over the top version with better drivers, an amp9 (hopefully by then in a BASIC version), and ... fuel cell powered.

I've struck a deal with some of people at IRD (http://www.ird.dk/) that they provide me with a free direct methanol fuel cell pack if I just print their logo on the speaker. IRD makes the only, as far as I know, commercially available fuel cells.

[Pano]

Originally posted by Saturnus
I've struck a deal with some of people at IRD (http://www.ird.dk/) that they provide me with a free direct methanol fuel cell pack

That rules!! Keep us informed. Fuel cell audio - I love it!

[v-bro]

Whoa! these things are capable of 1KW!! That's pretty massive for a festival speaker, maybe you'll end up being the festival!

[Saturnus]

Originally posted by v-bro
Whoa! these things are capable of 1KW!! That's pretty massive for a festival speaker, maybe you'll end up being the festival!

Hehehe. Yeah, well, it's the 100W RMS version I get. It should be more than adequate to run a 4x 100W amp9 provided I put in some BIG caps. I'm planning a 10 F ultracap bank.