hotrodding a Dayton DTA-2 (sonic impact) amp

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a while back, i bought a couple Dayton DTA-2 DIY modules as i refused to deal with paypal like ALL higher power module (& lepai) dealers make you do so i reluctantly settled on the lower power power modules to replace my similarly rated (and probably the same exact amp) sonic impact.

when i bought the module, i was expecting it to be a simple plug & play deal & didn't realize it needed assembly. in particular, i noticed that the choke coils need to be hand wound. when i tore my sonic impact apart, i noticed that there were maybe half a dozen windings in the toroid. would there be any advantage to adding extra windings and even making a true full toroid when i build the amps? my understanding is that they filter transient spikes. might doing so make the amp sound warmer or increase it's durability?

would upgrading the capacitors that bridge the speaker jacks make any difference either?

if i have to settle on a puny 10wpc amp when i REALLY want a 50wpc, is there anything i can do to make this one either sound better or last longer?
 
The output inductors are for filtering out the class t switching noise. You can mess with them, like switching to bigger units and different cores, but you need to keep the turns the same. Its also the reason why you cant hook them up to headphones, a filter for a 4-16 ohm load is not going to work on a 64ohm pair of cans:nownow:
 
v3 bypasses everything on the board and all your replacements are air wired, mainly because they are huge. v2 trys to use the existing input points and stock component locations.

Both do the same thing.

For caps i recommend either 1 of these:
Dayton Precision 1% Metallized Polypropylene Capacitors at Parts Express

or if you have the space, several of these:
Dayton Film Caps at Parts Express

your cut off freq needs to be 3 ocaves lower then your lowest freq. so your input is 20k so do the math:

Guitar Pedals: R-C Filter Calculator

you only need 1uf to play down to 30hz or so, 2.2uf is good for 14hz, very low. To big of cap and your highs will be attenuated.
 
v3 bypasses everything on the board and all your replacements are air wired, mainly because they are huge. v2 trys to use the existing input points and stock component locations.

Both do the same thing.

For caps i recommend either 1 of these:
Dayton Precision 1% Metallized Polypropylene Capacitors at Parts Express

or if you have the space, several of these:
Dayton Film Caps at Parts Express

your cut off freq needs to be 3 ocaves lower then your lowest freq. so your input is 20k so do the math:

Guitar Pedals: R-C Filter Calculator

you only need 1uf to play down to 30hz or so, 2.2uf is good for 14hz, very low. To big of cap and your highs will be attenuated.


Thank you for the answer, very much appreciated. Just one more question though, in the V3 there are two pics that show the mod.

Sonic/Tripath

One shows Electrolytic caps with a value of 2.2uf and the other shows some Auricaps with a value of 7uf. I have both values on hand as I do some speakerbuilding, so which should I use?

Ok I went back and just noticed it does say 2.2uf they just have a different cap in the picture.
 
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your cut off freq needs to be 3 ocaves lower then your lowest freq. so your input is 20k so do the math:

Unless you want to take advantage of the filtering naturally but even as a sub cut filter SQR 2 of the intended audible range is probably the closest you should aim for in an input filter, if you need more precise filter than that calculate a 2nd order L-R filter and take the highest filter frequency on the passive side and the lowest on the input side.
 
so for my purposes then, there really isn't anything non-technical i can do to get more output from the amp except unplugging the ports on my mission bookshelfs i'm taking it. i wish i could bridge my two units to double power but know that can't be done.

thanks for your help everyone. i'll leave the advanced tweaking to the rest of you as most of this thread's replies went over my non-circuit building head.

Its also the reason why you cant hook them up to headphones, a filter for a 4-16 ohm load is not going to work on a 64ohm pair of cans
taking a headphone level input & then amplifying it is a bit of overkill and only adds and extra layer of distortion to the circuit path. i guess maybe you're talking about using it with line in. i'll be using my amp with an excellent sounding cowon media player that's biggest fault is having slightly less treble air than a sony DVD player with uncompressed WAVs.
 
what about putting a heatsink on the chip or on the big "solder field" (i don't know the technical term) on the back of the amp for improving reliability? i plan on driving the amp just up to the level where i can hear distortion for continuous use about 4 hours at a time. my previous sonic impact amp eventually blew up. it would play fine for about 2 minutes then distort & fade.
 
Solder field is called a thermal pad. You can put a heatsink on the thing. I was suprised how much cooler mine ran just laying it on a piece of thermal rubber and an alum plate, at an angle even.

The only other way i can think of to get more power out of it is to figure the max voltage limit of the chip and tweak the power supply. It would have to be regulated.
 
i'm going to be using my amp with 8 X AA (2500mH energizers) as i did when my sonic impact was still working. what i REALLY wanted was a higher power sure or connexelectronics unit but both vendors are paypal only and i have a "fool me twice" grudge against paypal/ebay (same company). i particularly like the both the symmetry and the black on black look of the sureelectronics' TK2050 "100w" over the fugly yellow of the connexelectronics' 70w amp. i would have liked to put a TK2050 under a plexi window with deep cobalt blue (UV simulated) LED lighting.

never heard of "thermal rubber". my understanding is that anything between the surface & one is cooling other than the heat sink (or pipe) including thermal paste lowers efficiency & that a properly lapped direct connection is best. i also considered elevating the amp & putting a tiny fan on it.

i'm taking it then, that a heatsink would work better on the back of the amp on the thermal pad then. it makes sense as metal conducts heat better than the plastic on the chip. i'm sure the amp would be happier with some extra cooling doing long stretches at full power.

thanks for the help there. now to find a small enough heatsink, preferably copper.
 
it wasn't easy finding smaller heatsinks at all. early on, i found these EXCELLENT ones for the job, coolinnovations 4-070508P splayed copper heatsink
17.27mm L 13.72mm W 20.32mm H, but they appear to be one of those big companies that can't be bothered to deal with small orders.

i found a bunch of small copper ramsinks that would work, but they're a bit overpriced at $20 a kit. the heatsink would cost as much as the amp itself there.

the best ones i could find for sale individually were these black annodized aluminum finned 20mm X 14mm X 7mm units
http://www.electronicplus.com/images/products/EC-HS-E.jpg

there's space on the back of my amp for up to an 17mm W X whatever L heatsink except one of the corners of the thermal pad is cut at a 45 degree angle with another line of solder that would short out if i went that wide. do thermal pastes & tapes insulate against electricity, or would they cause shorts?
 
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i'm 100% sure a ramsink is better than nothing (but not worth $20 in this lifetime) as the amp module will work for at least a couple weeks worth of full volume without one, but i was looking for an overkill solution.

if bridging circuits is a bad idea, then i just won't do it and will work within the confines of the thermal pad then. thank you for clearing that up. i figured it was probably a bad idea but was hoping i could put a big porcupine heatsink in there.

before i buy one online, i'll see if i can find an old CPU unit i can cut down with a hacksaw at the local recycle store. i'd still like to get as big a contact patch as possible. if i can't find anything suitable, i'll just get a couple of those 14mm X 22mm finned aluminum deals. they're about the perfect size and only a couple bucks each.

i think before long, i'll just clench my teeth tightly and deal with scampal to get a 70wpc connexelectronic amp. 15wpc disappears the second you ride within 50 feet of a nightclub. if they weren't $100, i'd get a 50wpc Dayton DTA-100, but i can DIY a more powerful & possibly better sounding unit with the connex units.

thanks again
 
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