New ta2020 pcb'S

[tubesteve]

so, i think, as we don't work for the NASA on the Mars projects, let's see things a bit more relaxed. nothing is perfect in this world, the most imperfect are we humans anyway. a component is more predictable despite its difficult job.
Components have their specific side effects ( parasitics) as we have too.
a class d amp IC has also a lot of imperfections itself.
i understand that everyone wants the best. but the "absolute best" without parasitics is not possible. only the approach. our daily electronic engineering target is, to find a way, also for the costs.

[milo52]

Originally Posted by musicofthespheres

Hi, I'm new here to this board. I've got two of the MkIII boards, one for me and one for a friend. I'm a jeweler by trade, thus technically minded and detail oriented, but certainly no electrical engineer, so please excuse any painfully basic questions. As these boards are not arriving with any sort of instructions, I'm grateful for the helpful info available here, Arjens input, as well as the participation of Tubesteve, as he seems to be doing some design work with Arjen. Stacy, through my Ebay communications, let me know he's been a lot busier lately with some new full-time employment.

Re: the MK III Yes, the green terminal is for AC. I'm curious about the AC volts I've heard mentioned in this thread, as Arjens response to me was thus....


I'm waiting to hear back from him why this board included this design feature and what are the relative benefits of either.

If someone here would answer what I'm sure is a very simple question about grounding, I've got my SMPS (from Arjen) wired with the third ground wire. From the PSI have the black and red wires going to my board Arjens response to this question was



My question is, Have I succeeded already? Does my black power line which runs to the V- on the PS, which is itself grounded by the third line in from the house socket, mean my board is now successfully grounded? Or do I need to do some additional wiring or magic? I don't really know yet how to confidently translate his words to physical wires/screws/holes/etc.

In a related concernI purchased a previews version board and after about 50 hours of use both on house currant and ultimately on a battery. After 15 hours on the battery out camping it died (with a bit of a toasted electric smell) After this incident, Arjen said these amps are sensitive to static electricity and grounding is therefore important. Does this work to some degree? My housing is glass with some steel. I asked about grounding when using a battery, he seemed to feel it not necessary to ground to earth while using a battery, but I forget if there was some recommendation to go to some amount of housing or metal. Do folks sometime ground to the metal housing being used? If so, would that be accomplished... by what, running a spur line off of the negative power line? Thanks for your patience and help.

No need for any other ground besides the power supply negative, which is on the card several places. I am an electronics tech and deal with grounding issues a lot, ie. signal ground, power ground, earth ground etc. The reason your amp smoked..who knows..

[audi0]

Originally Posted by tubesteve

so, i think, as we don't work for the NASA on the Mars projects, let's see things a bit more relaxed. nothing is perfect in this world, the most imperfect are we humans anyway. a component is more predictable despite its difficult job.
Components have their specific side effects ( parasitics) as we have too.
a class d amp IC has also a lot of imperfections itself.
i understand that everyone wants the best. but the "absolute best" without parasitics is not possible. only the approach. our daily electronic engineering target is, to find a way, also for the costs.

Personally I gain a whole lot of pleasure in tinkering around building and modifying stuff, it is one of my pastimes and I really enjoy it. I have two other class D amplifiers that I could use in my study / workshop, but being a bit bored one day I thought that I would buy one of these to see what improvements I could get out of it. I am not trained in electronics, but do have a background in mechanical / electrical engineering, the electronic knowledge that I have gained has been picked up ‘along the way’. I am quite well aware of the limitations of design concept, but as previously noted, my intent was to make the best that I could out of it, and share my experience with fellow travelers

[frankquietly]

Hi I am loooking for some advice please.

I am interested in using one MKIII Tripath TA2020 and one Tripath 3 X TA2020 for a 8 channel amplifier.

I have a sound card with 8 channel RCA outputs http://www.softcam.gr/ASUS_XONAR_HDAV_001.jpg that would provide the signal and would like to use a computer 12v power supply NQ-4350GP-FL - 500W NorthQ Pacific II Fanless PSU, ATX 2.2 +80%+ Efficiency - 0Db Noise!! - Scan.co.uk to power the amp boards.

Is this going to work?

Also I would like to have a master volume pot and individual pots for each channel, plus spare 2 channel RCA inputs for the TA2020.

Now as I have not built an amplifier before perhaps it is too ambitious. What do you think?

Arjen, can you provide me all the things i will need?

Kind regards
Chris

[audi0]

Originally Posted by frankquietly

Hi I am loooking for some advice please.

I am interested in using one MKIII Tripath TA2020 and one Tripath 3 X TA2020 for a 8 channel amplifier.

I have a sound card with 8 channel RCA outputs http://www.softcam.gr/ASUS_XONAR_HDAV_001.jpg that would provide the signal and would like to use a computer 12v power supply NQ-4350GP-FL - 500W NorthQ Pacific II Fanless PSU, ATX 2.2 +80%+ Efficiency - 0Db Noise!! - Scan.co.uk to power the amp boards.

Is this going to work?



Also I would like to have a master volume pot and individual pots for each channel, plus spare 2 channel RCA inputs for the TA2020.

Now as I have not built an amplifier before perhaps it is too ambitious. What do you think?

Arjen, can you provide me all the things i will need?

Kind regards
Chris

Hi Chris,
Possible, absolutely, ambitious for a first time project, probably! But if you are passionate and enthusiastic about trying, give it a go!
You might have a bit of trouble finding a good 8 channel pot, DACT have a good one DACT audio attenuators do some research and you will get there…
Personally I’m not a fan of SMPS, linear supplies are soo much better for audio applications

Cheers.. Steve

[frankquietly]

Thanks steve, It does seem a large bite to take.

Thanks for the link to the DACT 8 channel pot, they are a very expensive component and would likely break the budget. I was wondering if their is a way to link 8 linear pots so they can be operated independently or all at once by a master linear.

Regarding power supplies, I presumed SMPS would be fine as the 6 channel board has this anyway, and I am not yet an audiophile, more of a convenience / minimalism phile.

Decisions decisions, is there a better approach to an 8 channel amp with a small footprint?

Thanks a million
Chris

[audi0]

Hi Chris,

you might want to read the 'Lightspeed Attenuator' thread on this site, I think this circuit is expandable to 8 channels. I think you might have a few problems trying to link single pots together Otherwise, I guess there is the digital option?

[calypso]

some noob questions for a good willing replier, about this arjen ta2020 mkIII amp

has anyone had experience in paralleling 2x4ohm speakers? is it possible?
or i should consider paralleling only with 2x8ohm speakers?

any tips on using a dvc 4+4 sub?
is there any good news on bridging?

if i decide to attach this pcb to a pair of 4ohm speaker per channel, is there any mod you can suggest to lower the real impedance from 6,6 ohms to 4 ohms? will it be worth for obtaining a "noticeable" upgrade?

and should i change input capacitors or apply an audio transformers to match the input impedance of the mkIII?

thanks for your kind attention folks

[calypso]

anybody did realize a 100hz high pass by switching input capacitors on arjen's ta2020 mkiii?

from his information, i should apply a 1mf cap instead of the furnished 2.2mf.

but maybe i'm doing something wrong.

have you got any resources, which kind of high pass filter is this? 1st pass? second pass? butterworth, bessel? sincerely i'm quite confused.

thanks for your kind reply

[calypso]

sorry i did not mention that resistors are 20k, and i tried to apply two 0.47uf in series instad of the 2.2uf one. what shall be amp behaviour at 40hz if two 0.47uf caps in series are applied?