Author Topic: BADA amplifier users thread (Read 86421 times)

JojoD818 · « **Reply #510 on:** Jan 27, 2009 at 10:34 AM »

Just to clarify some assumptions and text messages that I received...

The amp in question is a BADA DC-200 and for the past few weeks I have been painstakingly trying to find out why it hums. I requested schematics but what the tech support sent does not correspond to the actual unit I have here (it's time for festivities in China), and so I have to do it the old and hard but proven way of reverse engineering the amp to try and understand what is going on.

In the virtue of fairness, I find nothing wrong with the circuit design, nor did I find anything new that I haven't seen in other solid state amps. For the technically initiated friends we have here, there's a symmetrical differential stage at the input along with their corresponding cascodes and back to back current mirrors and the story goes on along the multiple output stages - sorry, no new circuit technology/implementation/technique to play around with. It's a textbook case actually, but a proven one too.

So what's wrong? The only thing I could think of that could cause such a hum problem is grounding.

We already know that the circuit design is not the problem, I reiterate that especially for those who sent text messages, phone calls asking me what is wrong. The problem is the printed circuit board (pcb) design, signal and input ground traces are routed along large current carrying ground return paths instead of having heir own trace going to the center of the main filter caps. Even the zobel (boucherot cell) is routed there, good thing is that the speaker ground return wire is hardwired to the psu ground.

As with everything else in life, this is not 100%, but this sure is the most probable cause of the hum in my book. As for the solution, well, I was brought up to believe that there is always a solution for every problem but I'm afraid I have to leave it at that for now for I'm a bit busy with a non-electronic project at the moment.

Full HD 3D · « **Reply #511 on:** Jan 27, 2009 at 03:08 PM »

Sir Jojo, Pardon me, i don't know any technicality about spec and so on, but were all the other branded solid state amp you have seen supposedly wiring done this way? Or just some Bada unit are wired incorrectly in this case,vtec3,riven 319& mine having this humming sound, while other Bada owner does not encounter any problem regarding their respective amp?

**In my opinion Bada should come out with an official statement why this humming sound occur since its been proven by our Master DIYers that this humming sound do exist . Bada products have following here in the Phil. and sold quite a few. Silence might not be golden at this point. Maybe Matz can direct the Engineers of Bada to this site and they can have some exchanges with our own PDVD DIYers and gurus. Then for none techie guy like me and some others, we learn. As suggested by TonyT. Its a community service.

MAtZTER · « **Reply #512 on:** Jan 27, 2009 at 03:33 PM »

Quote from: TonyT on Jan 25, 2009 at 05:13 AM

any updates?

you know, seller-buyer relationship does not end with payment or delivery of goods, there is such a thing as after sales service.....

if i were the seller, i would dispatch two of my techs to your place to investigate....

the findings can then be reported here to help others in the same predicament....this is comunity service, legaly seller is not bound, but for sake of delicadeza seller should do this...

my 2 centavos....

FYI, we even picked up the amps from ernie's place. It has been brought to service 2 times and techs cannot find any humming at their setup. Neither did we find any humming at our office when tested. Its worthy to note that the 3 amps did not have any humming in ernie's old house.

The last request of the techs was to borrow the pre-amp, but thats too tedious work already, thus we had to look for another alternative. So we decided to have JojoD look into the issue. The next problem was during that time, China is on a long 2 week holiday, thus we werent able to properly acquire the schematics needed by JojoD. So I would request a bit more patience (after their holidays) before we jump to conclusions or insinuate stuff here.

patience lang bros.

KUNG HEI FAT CHOY!

MAtZTER · « **Reply #513 on:** Jan 27, 2009 at 03:41 PM »

Quote from: ZENshey on Jan 27, 2009 at 03:08 PM

Sir Jojo, Pardon me, i don't know any technicality about spec and so on, but were all the other branded solid state amp you have seen supposedly wiring done this way? Or just some Bada unit are wired incorrectly in this case,vtec3,riven 319& mine having this humming sound, while other Bada owner does not encounter any problem regarding their respective amp?

**In my opinion Bada should come out with an official statement why this humming sound occur since its been proven by our Master DIYers that this humming sound do exist . Bada products have following here in the Phil. and sold quite a few. Silence might not be golden at this point. Maybe Matz can direct the Engineers of Bada to this site and they can have some exchanges with our own PDVD DIYers and gurus. Then for none techie guy like me and some others, we learn. As suggested by TonyT. Its a community service.

How will they exchange here? In Chinese?

Please be patient and dont jump to conclusions yet, we are trying to solve the problem.

ATJr. · « **Reply #514 on:** Jan 27, 2009 at 04:07 PM »

Quote

In the virtue of fairness, I find nothing wrong with the circuit design,

exactly my thoughts too, i wouldn't jump to conclusions until i see the design.....

perhaps some pictures of the inards of the amp...and the user's set up may shed light into this matter...

Full HD 3D · « **Reply #515 on:** Jan 27, 2009 at 04:13 PM »

Its worthy to note that the 3 amps did not have any humming in ernie's old house.
After buying the amp. I have tested one and noticed there's a hum on 1 unit. I texted immediately to Matz. but since Matz suggested that it might be the speaker wire and power chord were mess up all together. I dismissed it since it might be due to the clutter and we were moving to our new place already. After a testing it in the new home. All three units produce this humming sound. All 3 units were plugged to a Bada Line Conditioner to a dedicated line that's well grounded since it was my spec. with the contractor (Pls. read my post on my experience)

How will they exchange here? In Chinese?

Please be patient and dont jump to conclusions yet, we are trying to solve the problem.

I have been doing business with China medium scale company and they can communicate well in English since they now have the luxury of interpreter.By the way,Bada is doing business in Europe and USA.

I'm not jumping into conclusion, Matz, what i want is to learn what went wrong since its a fact that something went wrong. Riven unit(in his post) was purchased last Dec. and out of the box, there's this problem already.He find ways to rectify to no avail.(Did this guy get a solution?) Vtec3 unit also produces this humming sound and yet he did not find the answer. On page 13 of Bada Hybrid thread. A poster (Sanabagan) experienced the same problem, but sadly this post was not given a reply. So, getting a response from Bada even in CHINESE will not be a bad idea.
my 1 centavo lang po.

Full HD 3D · « **Reply #516 on:** Jan 27, 2009 at 04:59 PM »

Quote from: TonyT on Jan 27, 2009 at 04:07 PM

and the user's set up may shed light into this matter...

Sir,
For Audio i use a Primaluna Prologue 2 with a Njoeb Tjoeb CD Player. tap to a pair of Usher 6371(wired tweak by Diymaster. Oh! Sir, you should hear Jacintha breathe, the d & t&s ending of each phrase) No Humming problem whatsoever.
For movies & concerts i use a Denon receiver 3805 as pre-out currently powered by Rotel 1066 since the 3 Bada is on sick bay(come to think of it)Actually, I still have no chance to sit down and seriously listen to the Bada running my Usher. (Sir, you should also listen to how Carly Simon sing here) no humming whatsoever. Oppo 983 for DVD, PS3 for Blu-Ray, Toshiba Xa2 for HDDVD. Surround(Dipole & Direct) are produce by Castle Speakers (England). Bass by REL & SVS. All these equipments and settings were check by Diymaster(Anthony).No Problem too.
Room Treatment. Front Dead end Matz acoustic Panel(Excellent), side with all the bass traps, resonators & diffuser (Ideas,knowledge and computation courtesy of Threadlock. Consultation with fellow Pdvd streetsmart)
Thank You Sir for trying to help me solve this mystery.

Full HD 3D · « **Reply #517 on:** Jan 27, 2009 at 05:05 PM »

Quote from: macdon on Jan 27, 2009 at 10:07 AM

Sir, you might like to start a new thread about Emotiva -Im sure some folks would like to get more info about the brand and their products.
Nakakahiya kasi kay sir Matz as this is a bada thread

Ooops! Sorry. Got carried away.

ATJr. · « **Reply #518 on:** Jan 27, 2009 at 05:06 PM »

me too deals with the chinese, i buy tube sockets direct from china....

i believe you have a legitimate concern, let us just hope they get resolved in the near future....

lessons learned here can guide others with the same predicament....

i also pray that this does not turn into a finger pointing event, but simply a just resolution of a legitimate concern....

Full HD 3D · « **Reply #519 on:** Jan 27, 2009 at 05:17 PM »

Quote from: TonyT on Jan 27, 2009 at 05:06 PM

me too deals with the chinese, i buy tube sockets direct from china....

i believe you have a legitimate concern, let us just hope they get resolved in the near future....

lessons learned here can guide others with the same predicament....

i also pray that this does not turn into a finger pointing event, but simply a just resolution of a legitimate concern....

Likewise,Sir. I really am curious what really happen!!
Thank You Sir for your inputs. It really help us non-techie guy.

JojoD818 · « **Reply #520 on:** Jan 27, 2009 at 08:09 PM »

Quote from: ZENshey on Jan 27, 2009 at 03:08 PM

Sir Jojo, Pardon me, i don't know any technicality about spec and so on, but were all the other branded solid state amp you have seen supposedly wiring done this way? Or just some Bada unit are wired incorrectly in this case,vtec3,riven 319& mine having this humming sound, while other Bada owner does not encounter any problem regarding their respective amp?

**In my opinion Bada should come out with an official statement why this humming sound occur since its been proven by our Master DIYers that this humming sound do exist . Bada products have following here in the Phil. and sold quite a few. Silence might not be golden at this point. Maybe Matz can direct the Engineers of Bada to this site and they can have some exchanges with our own PDVD DIYers and gurus. Then for none techie guy like me and some others, we learn. As suggested by TonyT. Its a community service.

As far as the other power amps (seps and int) that I had the pleasure of opening up are concerned, the answer to your question is no. For example, Rotel's RB-981 power amp and NAD C352 integrated amp, their power ground, signal ground, and chassis grounds have separate ground paths that meet in one point (star grounding). This is also true even for tube amps, consider the Conrad Johnson MV-52 tube power amp, it also has a printed circuit board that follows the star grounding conventions.

Just to clear things up, the electronics inside are not "wired", they have a trace/path in the pcb. I don't know if your amps pcb, along with those who have the same problem have different board "revisions" from those others who have bought the amp but did not experience your problems.

JojoD818 · « **Reply #521 on:** Jan 27, 2009 at 08:15 PM »

Quote from: TonyT on Jan 27, 2009 at 04:07 PM

exactly my thoughts too, i wouldn't jump to conclusions until i see the design.....
perhaps some pictures of the inards of the amp...and the user's set up may shed light into this matter...

right, let's figure the cause of the problem and find the solution...

ATJr. · « **Reply #522 on:** Jan 28, 2009 at 05:01 AM »

here is another thing you can do....you can email the manufacturer directly, stating the model number and serial number of your amp, and then also your current setup, just as you described in your post above.

let us find out what their response would be....

MAtZTER · « **Reply #523 on:** Jan 29, 2009 at 03:14 PM »

Quote from: TonyT on Jan 27, 2009 at 05:06 PM

i also pray that this does not turn into a finger pointing event, but simply a just resolution of a legitimate concern....

You may have prayed too late sir, read the above posts again, werent fingers pointed already while the solution was still being sought? Are they helping at all in the resolution of a legitimate concern? Let me also pray for patience!

Quote from: ZENshey on Jan 27, 2009 at 04:13 PM

I have been doing business with China medium scale company and they can communicate well in English since they now have the luxury of interpreter.

Then you should understand how hard it is to communicate with them during their 2 week long holidays, even with an interpreter. I have emailed and even made long distance calls in your behalf but no response - Even in Chinese...Well, the automated "the # you dialed is unavailable" was in Chinese.

So the "silence is not golden" , and service insinuations (ahem), can be hasty & premature conclusions, since the answer to the problem really isnt known yet.

"Silence is golden" at this point is not really wrong, specially when the answer or irrevocable evidence isnt there yet.

Quote

Riven unit(in his post) was purchased last Dec. and out of the box, there's this problem already.He find ways to rectify to no avail.(Did this guy get a solution?) Vtec3 unit also produces this humming sound and yet he did not find the answer. On page 13 of Bada Hybrid thread. A poster (Sanabagan) experienced the same problem, but sadly this post was not given a reply.

Riven's unit was given the Bada 30 day money back guarantee since it was below 30 days. Read their posts, and the humming does not bother Vtec3 enough to ask for service. But we will service it if he requests. After we find out whats wrong with your unit, we will service Sanabagan's and Vtec upon their request.

I even offered you a service unit but you did not answer. Replacement is questionable since it may exhibit the same problems in your setup (as the consultant said about this grounding phenomenon), w/c did not occur in many other buyer's setup. Money back at this point is of course, way less than reasonable.

As far as service is concerned we did everything we reasonably can. So I ask for reasonableness too on other's behalf. Please.

And of course, patience!

Full HD 3D · « **Reply #524 on:** Jan 29, 2009 at 07:54 PM »

Quote from: MAtZTER on Jan 27, 2009 at 03:41 PM

How will they exchange here? In Chinese?

Please be patient and dont jump to conclusions yet, we are trying to solve the problem.

THE POST BELOW WAS IN RESPOND TO THE ABOVE STATEMENT YOU POSTED.
I have been doing business with China medium scale company and they can communicate well in English since they now have the luxury of interpreter.By the way,Bada is doing business in Europe and USA.

Lets get everything in order so as not to sound too sarcastic. I' just a guy solving a problem. No pun intended. That's what we are doing here, to solve the problem. Patience is a virtue that i really believe.

Full HD 3D · « **Reply #525 on:** Jan 29, 2009 at 08:15 PM »

So the "silence is not golden" , and service insinuations (ahem), can be hasty & premature conclusions, since the answer to the problem really isnt known yet.

"Silence is golden" at this point is not really wrong, specially when the answer or irrevocable evidence isnt there yet.

This statement was taken out of context as my post was this. Please:
**In my opinion Bada should come out with an official statement why this humming sound occur since its been proven by our Master DIYers that this humming sound do exist . Bada products have following here in the Phil. and sold quite a few. Silence might not be golden at this point. Maybe Matz can direct the Engineers of Bada to this site and they can have some exchanges with our own PDVD DIYers and gurus. Then for none techie guy like me and some others, we learn. As suggested by TonyT. Its a community service.

Its only a suggestion and an opinion of mine to the request of a community service.
I have always praise your service as top notch and never in doubt. Dont mean any service insinuation.

Full HD 3D · « **Reply #526 on:** Jan 29, 2009 at 08:31 PM »

Riven's unit was given the Bada 30 day money back guarantee since it was below 30 days. Read their posts, and the humming does not bother Vtec3 enough to ask for service. But we will service it if he requests. After we find out whats wrong with your unit, we will service Sanabagan's and Vtec upon their request.

I even offered you a service unit but you did not answer. Replacement is questionable since it may exhibit the same problems in your setup (as the consultant said about this grounding phenomenon), w/c did not occur in many other buyer's setup. Money back at this point is of course, way less than reasonable.

As far as service is concerned we did everything we reasonably can. So I ask for reasonableness too on other's behalf. Please.

And of course, patience!

[/quote]
Riven 319 got 1st unit then another unit which both exhibit humming
Vtec3 have 1 unit with humming but did not request for service
Sanabagans post was not answered and was only brought up by me while i'm lookin for answer
Mine 3 units humming.
So can we safely say that Bada now have 7 Lemons got out of their factory?Can we check all this unit if their serial numbers are in consecutive order and same person who assemble this?

Yes, it is true that i was offered a service unit but did not respond as i see it as a waste of time. I never requested for any replacement or refund. See, as i have been saying your service is top notch.

John E. · « **Reply #527 on:** Jan 29, 2009 at 11:50 PM »

racksrus ikaw ba yan?

Huddaf · « **Reply #528 on:** Jan 30, 2009 at 01:10 AM »

I'm keeping my silence here til' this gets resolved. Will continue to monitor this thread for a concrete solution. I encourage everyone to do the same.

I have a bada myself.

Full HD 3D · « **Reply #529 on:** Jan 30, 2009 at 09:25 AM »

Quote from: JohnE. on Jan 29, 2009 at 11:50 PM

racksrus ikaw ba yan?

Sorry, I'm not racksrus whoever he or she is. I dont know your intention. Please do not muddle the issue. Thanks! Its a legitimate concern and lets not turn this into circus. Set partisan aside. Matthew is an acquaintance of mine, He knows me. But being that doesn't mean we cannot discuss openly issue like this, BADA CHINA should be proud that the Phil distributor is active and upgrading their products and its technicalities. GENTLEMEN.

Racks r' us is newly reopened restaurant, is it?

"A SPADE is a SPADE and will always be a SPADE"Lets leave it this way.

Full HD 3D · « **Reply #530 on:** Jan 30, 2009 at 09:55 AM »

I have a bada myself.
[/quote]
I introduced a Bada hybrid to a very dear friend of mine which currently being use to power the whole house pipe in music, it was sold through Audible Illusions. No problem that i know of until this time.

threadlock · « **Reply #531 on:** Jan 30, 2009 at 11:45 AM »

Quote from: JohnE. on Jan 29, 2009 at 11:50 PM

racksrus ikaw ba yan?

He is not. I know Ernie and he is a friend of mine also. I don't think he means to ruffle the feathers of sir Matz or Bada. I think he just have a legitimate problem that needs resolving. Im a bada owner myself and I don't have any problem with the unit.

Full HD 3D · « **Reply #532 on:** Jan 30, 2009 at 11:58 AM »

Quote from: threadlock on Jan 30, 2009 at 11:45 AM

He is not. I know Ernie and he is a friend of mine also. I don't think he means to ruffle the feathers of sir Matz or Bada. I think he just have a legitimate problem that needs resolving. Im a bada owner myself and I don't have any problem with the unit.

Thanks! Noel.
This is for the good of the community who has same interest with Bada products.
I sincerely hope Bada(CHINA) will look into this matter then their next product line will be something to watch out for after they come back from their drawing board. But we have to wait a little while more since the spring festival will end next week and chinese start trekking back to their work.

MAtZTER · « **Reply #533 on:** Jan 30, 2009 at 03:37 PM »

Quote from: JohnE. on Jan 29, 2009 at 11:50 PM

racksrus ikaw ba yan?

LOL, He isnt. Ernie is an acquaintance of mine and we have gone to each other's houses , had long talks and text sessions.

He is a nice guy.

Quote from: ZENshey on Jan 29, 2009 at 07:54 PM

Lets get everything in order so as not to sound too sarcastic.

I didnt mean it that way, you know I joke around a lot in person. But ok, lets try to get things in order.

Quote from: ZENshey on Jan 29, 2009 at 08:15 PM

I have always praise your service as top notch and never in doubt. Dont mean any service insinuation.

My apologies, I was counter-insinuating that to someone else.... It wasnt meant for you.

MAtZTER · « **Reply #534 on:** Jan 30, 2009 at 04:10 PM »

Quote from: ZENshey on Jan 29, 2009 at 08:15 PM

**In my opinion Bada should come out with an official statement why this humming sound occur since its been proven by our Master DIYers that this humming sound do exist . .

For the record, there is no denying that there is a humming noise. The 2nd time Ernie's unit was returned for service, I heard a slight hum at one inch away from the tweeter of a 92 db speaker. Jojo confirmed this and can hear from no more than a foot away, but from normal listening distance it wasnt audible.

Quote from: ZENshey on Jan 29, 2009 at 08:31 PM

So can we safely say that Bada now have 7 Lemons got out of their factory?

Here is the thing: I checked on my Rotel 985 a few days ago with pre-amp off. Guess what? It hums too at 1 inch away from my ears on a 90db sensitivity speaker!!! Ricky also read that this happens to other bigger Rotel amps in many forums. An expert I consulted says this phenomenon happens even to expensive PRO amps. These last 2 were mentioned on pages 1 & 2, but guess what?...ignored.

Is it safe to say that we got Rotel lemons?

I remember TonyT once mentioned: "You cant go wrong with a Rotel"

A question to ponder is: Did we go wrong with a Rotel?

Why is it being automatically pinned to be Bada's mistake alone when this phenomenon happens to other amps too? This is the part that really got me wondering.

Is this fair? :'( :'( :'(

The main point I like to stress, while we are trying to find the solution, is there should be IMPARTIALITY. If this "hums here, but doesnt hum there" phenomenon is to be harshly blamed on BADA alone, the other amps which exhibit this same phenomenon should be equally addressed too.

At the center, the problem is ground loop phenomenon...

My 2 cents lang po, and where is the Rotel service center?

Full HD 3D · « **Reply #535 on:** Jan 30, 2009 at 06:23 PM »

Matz, No harm done. I alway know that you are a fair person and a good christian.
ok. Lets get it on.wala ng kokontra,since we are now solving both the Bada and Rotel problem all at once.

To all Rotel & Bada owner, please share some inputs if you encounter this humming problem and lets all learn and share what we can do. DON'T BE SHY GUYS. THE MORE INPUTS,THE EASIER IT WILL BE FOR US ALL.
We are one community and inputs like this will help those in need. Thanks! Gentlemen

ATJr. · « **Reply #536 on:** Jan 31, 2009 at 05:25 AM »

Quote

Is it safe to say that we got Rotel lemons?

I remember TonyT once mentioned: "You cant go wrong with a Rotel"

did I?

okey let me modify that statement, "You can not go wrong with either Rotel or Bada" unless of course you end up with a lemon of a unit....and this is not surprising, the law on statistics says that there will be a few units falling outside of the bell curve....malas molang pag sa iyo natapat.

@Matzer, i do not think anybody can fault you for any legitimate concerns about you products for as long as you do your best to address them even if the results are still wanting, after all you merely distributed the goods, you did not design nor produce them......

as long as you are on the ball then you are okey...

John E. · « **Reply #537 on:** Feb 03, 2009 at 05:10 AM »

Quote from: JohnE. on Jan 29, 2009 at 11:50 PM

racksrus ikaw ba yan?

hi ernie! i was just asking cause "racksrus" is a big bada fan (like me) but he is unforgettable

he also boosts up bada sales

peace sir matz and ernie hope this gets resolved (as always)

Full HD 3D · « **Reply #538 on:** Feb 16, 2009 at 12:37 PM »

Matz. Any Update?

leomar · « **Reply #539 on:** Feb 16, 2009 at 03:53 PM »

Quote from: MAtZTER on Jan 30, 2009 at 04:10 PM

Here is the thing: I checked on my Rotel 985 a few days ago with pre-amp off. Guess what? It hums too at 1 inch away from my ears on a 90db sensitivity speaker!!! Ricky also read that this happens to other bigger Rotel amps in many forums.

I can also attest to this. With my setup, Yammy 659 + Rotel 1075 + Mission M3is, i can hear hum 1 - 4 inches from the tweeter @ -20DB. Increasing the volume to +10 to +15DB, i can hear the hum at my usual listening position.

Just backread this thread and i'm also interested with the update.