| ANALOG GUY |
My friend send me his pictures about 2400w CLASS-D, He told me that him bought it from CHINA.
But in CHINA he contact only dealer, Please Chinese member who known this model please suggest me for order and let me know its website.
Regard
Analog guy |
|
|
| boonthae |
:smash: i think it CLASS-TD but i don't know made in ...
search www.lab.grupen |
|
|
| audiosteve |
I'm not sure if that is a LabGruppen amp or not. In any case, the URL to check would be http://www.labgruppen.com
two p's in gruppen |
|
|
| Evan Shultz |
| PowerSoft is well known for 1RU class D amps, although it doesn't look like any PowerSoft I've seen. |
|
|
| Michael-Rifa |
This amplifier is manufactured in Thailand, designed by my self and the R & D team from the firm TAFN ENGINEERING CO.,LTD
D-TECH 2400 is a highly reliable advanced CLASS-D power amplifier capable of delivering high power over the whole audio band without overheating in a very small size. At the same time it is capable of reproducing sound with outstanding clarity and stability like never before possible with conventional amplifiers.
So far for what i hear, no other PA amplifier of this size and weight can match the power and sound quality.
Many PUBs and Discotheques in Thailand are changing ther systems from reliable class AB amplifiers for this new Class-D model ( D-TECH 2400 ). |
|
|
| MOER |
I find it interesting that the switchmode supply can only work from 140v to 260v AC.
So in countries that have 100-120v AC mains this amplifier is useless.
Also by the way there are no such things as "watts RMS". It is a non existant term.
Watts are calculated by measuring the volts rms multiplied by the current rms, and therfore RMS X RMS cannot = RMS.
The fact that the square root of 4 x the square root of 4 does NOT equal the square root of 4 but is just 4. There is no root mean square attached the answer of 4.
I would be interested to know how you measure the damping factor )not dumping factor) at 800 and you do not even specigy the load impedance. Damping factor is simply defined as the load impedance divided by the output impedance of the amplifier.
So assuming that 8 ohms was the impedance to which the DF was referred to this means that the output impedance is 10 milli ohms. The output coil will contribute more than this. |
|
|
| Lars Clausen |
| quote: |
Watts are calculated by measuring the volts rms multiplied by the current rms, and therfore RMS X RMS cannot = RMS.
|
Not quite.
You are missing the load resistance in your calculation. The power is normally calculated as:
Vrms ^2 / Zload.
So the term Watts RMS is good. :cool: |
|
|
| Michael-Rifa |
| This amplifier IS NOT DESIGNED FOR 110V. countries. Is designed to be used in Thailand wich is 220V. and can take voltage fluctuations in that 220V countries. Not in the US. |
|
|
| MOER |
Dear Lars,
Maybe you should check your mathematical skills.
The calculation for power in watts ALWAYS contains either volts squared, amperage squared OR volts x amps.
In any of the three calculations, the voltage and current are RMS terms and in each of the three an "RMS number" is multiplied by an RMS number so how can the answer be a root mean square number?
The load resistance will determine the current so it is quite OK to use the current value as part of the calculation.
So to help out watts may be calculated with three formulas
1) Volts RMS x amp RMS = watts
2) Volts RMS x volts RMS divided by load impedance = watts
3) Amps RMS x amps RMS x load resistance = watts |
|
|
| Michael-Rifa |
Our amplifier have very high dumping factor due to the analog negative feed-back taken from the very speaker output wich normaly is not posible with convencional Class-D.
Our Class-D uses a new more advanced technology wich solves many problems found with convencional class-d designs.
And Mr. MOER don't try to be an expert with so elemental things that everybody with a litle bit of knowledge already knows. |
|
|
| koolkid731 |
0.1% THD is not that great. At what power level and frequency?
OK it's very loud, like PA should be. |
|
|
| IVX |
| quote: | Originally posted by Michael-Rifa
Our amplifier have very high dumping factor due to the analog negative feed-back taken from the very speaker output wich normaly is not posible with convencional Class-D.
|
it would be impressive for 2000, but not for 2007. :) |
|
|
| MOER |
Dear Michael,
There are many designs which take feedback from after the low pass filter.
What is "conventional class D"?
What more advanced technology are you using? Your THD numbers are not great, there are quite a few designs with THD far below your 0.1% |
|
|
| Richard Ellis |
There is nothing more irritating than companies selling products internationally when the texts of said products have blatant grammatical or spelling errors.
With teams of marketers, engineers and executives, the grasp of the English language seems to elude them.
___________________________________Rick.......... |
|
|
| Michael-Rifa |
Mr.Richard Ellis, Our product is NOT intentionaly made to sale overseas, ONLY THAILAND. But is overseas countries that are intrested in our product. So do not complain in the speling as we already sale enough in Thailand and we do not need to sale overseas, besides i'm not in the sales department but R & D department and i write in the forum just for fun.
Mr. Moer The dumping factor and other factors such as THD, when the numbers are good enogh, there is no need to make it better as you are not going to feel any diference at all, and we prefer focus in other aspects that do make a diference and they are noticable.
Dumping factor more than 50 is normaly more that enough and do not make any diference if higher than that.
Our technology makes the design very stable and reliable for a class-d amp but i'm not going to reveal how as it is company policy. |
|
|
| IVX |
| quote: | Originally posted by Michael-Rifa
Mr.Richard Ellis, Our product is NOT intentionaly made to sale overseas, ONLY THAILAND. But is overseas countries that are intrested in our product. So do not complain in the speling as we already sale enough in Thailand and we do not need to sale overseas, besides i'm not in the sales department but R & D department and i write in the forum just for fun.
|
Michael, indeed Post #16 is rather mistake and maybe intended for another thread. By the way, how much a cost of your amp in Thailand? |
|
|
| Eva |
MOER:
If you multiply RMS voltage by RMS current, you get average power (also known as RMS power). Then again, Root-of-Mean-of-Squares is a mathematical averaging method (the square root of the integral of the magnitude squared).
Michael Rifa:
At least your product looks somewhat original and you are not trying to sell it here. Note that there are other companies in Asia and India that seem to be selling clones of amplifier models made by well known European and North American firms. Fortunately you seem to be a few steps ahead of them, although after the UcD boom, low-distortion, high-bandwidth, low output impedance, complete damping of filter resonance and post-filter feedback are becoming standard class D features. |
|
|
| Workhorse |
| quote: | Originally posted by Eva
Note that there are other companies in Asia and India that seem to be selling clones of amplifier models made by well known European and North American firms. |
EVITA THIS IS BLATANT LIE IN THE CASE OF INDIA...............
THERE IS NO AMPLIFIER MADE IN INDIA BY ANY MANUFACTURER WHICH IS A DIRECT OR INDIRECT COPY OF ANY EUROPEAN OR NORTH AMERICAN FIRMS, GET YOUR FACTS CORRECTED!!!!!!!! |
|
|
| Andrewbee |
All this **** because of one persons question as to where to find an amplifier.
Why all the bickering !
Chill out people.
Andrew |
|
|
| BWRX |
| quote: | Originally posted by Eva
Note that there are other companies in Asia and India that seem to be selling clones of amplifier models made by well known European and North American firms. |
| quote: | Originally posted by Workhorse
EVITA THIS IS BLATANT LIE IN THE CASE OF INDIA. |
Eva, there are sleazy companies all over the world (not just in Asia and India) that clone or copy both good and bad designs from well known companies.
Kanwar, there's no need to YELL or to take such comments personally.
All, please keep it on topic or the thread will be closed. |
|
|
| Workhorse |
| quote: | Originally posted by BWRX
Kanwar, there's no need to YELL or to take such comments personally.
|
Look Mr.Moderator.................You cannot expect me to believe on a Blatant lie which is wrongly subjected on my country.............Its not a personal thing........OK |
|
|
| weissi |
hmm, going very o.t.
one should not be angry about some bad words about the country one is living in. That hasn't anything to do with one personaly. Otherwise, what sould I say, living in a country that 80% of all people all over the world associate with Nazis...
peace! |
|
|
| gingerpimp0069 |
I'm with the Austrian, chill fella's - i take it most of you don't work in gobal companies, understanding W-english (World-English) is a 2 or 3 message event rather than getting it right first time (which many natural english speakers don't do anyhow!)....if this was an english language forum then i'd say nothing and let you get on BUT at the mo (mo=moment) this sounds like a BHP (BHP=Brake Horse Power) thread on a car forum!
danny:angel:
p.s. to mimic is to flater, it happens in the product market worldwide :devilr: you are dreaming if you think it doesn't :cannotbe: ...thats why patents are nice BUT not infallible:( |
|
|
| vectorplane |
I understand that some of the more seasoned members here have seen, over the years, a number of audio products sold by companies in the Pacific Rim, which, although competent designs, would go just a bit overboard with the hype.
Talk of "Advanced Technology" and "Secret Technology" has been associated before with deceptive marketing, and massaged specs.
So, it is not altogether surprising, that members here would scrutinize anything that makes impressive claims, whether it is actively promoted in the group, or just casually mentioned.
I would not think the 140 volt lower Vin limit should prevent any intrepid North American enthusiast from using this product.
It is obvious it uses an SMPS, (the low-profile case gives it away.)
Sooo,.. any SMPS is bound to full-wave rectify the AC line, somewhere not too far from the AC power input point.
Access the rectifier bridge, and rewire one node to create a voltage doubler. Voila!
That's how a lot of commecrial SMPS powered equipment does it, by doubling 120V to 240V. It's a design handicap to work with the higher currents inherent in 120V systems, so many designers won't go there.
Don't like to break your product warranty? (what's the matter, you're counting on shipping this thing back to Thailand for repair? :) :) )
Just build a duplicate AC front end external to the unit, which includes the common- and differential- mode filters and a voltage-doubling bridge rectifier, and feed the DC to the unit's mains receptacle. The SMPS inside will never know the difference.
And the series fuse and inrush-current limiter inside the case, will also be in series with your external unit and protect it.
I'm not sure if RMS units specifications is worth picking at, under the circumstances, we're better off focussing on bigger things... :)
And before picking at the distortion figure, maybe we should ask about the price. It may put things in perspective. |
|
|
| vectorplane |
And Oh, yes..
if you do the stunt with the external front end and voltage doubler, you may slightly increase the harmonics fed back into the AC line.
But then again, if you're doing this, you live in a place where many engineers cannot say "regulatory agency compliance" without bursting into laughter.
( and these are the engineers from the power company ) |
|
|
| JesseG |
Right on, vectorplane - let's get a little calm(on) sense in this thread.
I am really dissappointed in some of the earlier posts. If you all are so smart, go out an research, design, test, manufacture and sell your own giga-watt, class whatever amp and then you may have a basis for criticism. Of course if you purchased this product and had some difficulty with it... :grumpy:
I am very pleased that one of the designers took the time to provide some information on his work. We should be asking questions that will help us learn and appreciating the answers, not slamming someone from the lofty towers of our own ignorance. :whazzat:
I for one would like to appologise to Michael-Rafia for the inexcusable BAD MANNERS of some of the other posters to this forum.
| quote: | | I would not think the 140 volt lower Vin limit should prevent any intrepid North American enthusiast from using this product |
Or, you could just wire a 240V circuit from your power pannel to your listening room (I have ;) ).
I would be very interested to know how much this product - say the DTECH-2400 - sells for in Thailand. |
|
|
| vectorplane |
I cannot comment on the product, I have not used it or tested it.
But one thing I find refreshing: here's one manufacturer who believes that SLIM is SEXY.
it seems most high power amps (especially the home-made ones) are fat and stocky.
Of course it's very difficult to reduce the height of your amp beyond a certain point if you insist on using large toroidal transformers.
I find the attention given to compactness very interesting. And the case hardware seems to be top-noch, with a lot of attention paid to the sheet-metal forming work, all serving to keep size down.
Of course, the Disco and bar setting is not exactly a very demanding test for amplifier THD and S/N ratios.
At the powers used, a large number of things around the room will vibrate (tables, chairs, floor, walls, glassware, fixtures) and multiple delayed interferances from bouncing waves, will produce an inherent level of perceived distortion that will probably mask anything below 0.5THD. And of course, overlapping songs without gaps, will take care of the S/N ratio. :) |
|
|
| Eva |
| In a disco environment (depending on venue size) a hundred or thousand people talking loud and shouting will take good care of things such as S/N ratio and stereo cross-talk :D:D:D You actually need an efficient PA and powerful amplifiers to make the music dominate over the ambient noise. In these circumstances, what you need is moderate distortion until very loud :D and bullet-proof limiters to prevent the system from self destructing when the party is going to an end and the DJ sets to maximum all volume and gain knobs for the few last songs. |
|
|
| fredos |
Hi Eva..
You should come to Montreal, I will show you some Club and bar that you can speak event at 125db, so you will hear distortion, crosstalk and S/N ratio with music...I think we dont have same club all around the world....We have past the age of loud and agressive music (specialy a bosst of 12db at 2Khz!) to reach a near hi-fi powerfull quality sound.....:-)
Fredos |
|
|
| Eva |
| Tonight I will be working at a closed venue with 2000 teenagers shouting, most of them drunk or high from other drugs. They produce a nice 100dB noise floor... |
|
|
| fredos |
| Prety sure they do 100db of noise with distortion! ;) |
|
|
| speaker |
| quote: | Originally posted by Andrewbee
All this **** because of one persons question as to where to find an amplifier.
Why all the bickering !
Chill out people.
Andrew |
Every forum, any topic, it seems.
Everyone has to play "Gotcha!"
Thanks Andrewbee for bringing in back to normal.
:) |
|
|
| peranders |
| Michael Rifa, your products look very nice I think and I'm sure they will do a good job for where they are intended to be (not at home). For PA you must trust the gear. The distortion doesn't have to be 0.00047% |
|
|
| Michael-Rifa |
Yes indeed, this product is intended to be used as a PA system and what is most important in this case is relaiability and robustness of the amplifier as it is going to be transported from concert to concert os show and it has to withstand voltage fluctuations, short circuits in the load etc.
But i also had tested it in a class-A home system and i swich from one amp to the other and they are not able to tell the diference.
As i said before there is no need to make 0.0001 THD as the speaker and your ear already has a much higer distortion level. And you don't need more than 20 damping factor or even less as the voice coil of the speaker already has 5 ohm or more of wire resistance plus the speaker cables.
We already are well about this numbers: Damping factor 800 and 0.1% THD and 0.05 IMD etc. |
|
|
| fredos |
Can you export quantity and do OEM?
Fredos
PM me please... |
|
|
| Pabo |
Eva
What do you mean by UcD boom? |
|
|
| peranders |
| quote: | Originally posted by Pabo
Eva
What do you mean by UcD boom? |
Possibly the success with Hypex modules :scratch: |
|
|
| Pabo |
Peranders
I just got the impression by the word "boom" that more companies than Hypex are using UcD. |
|
|
| Eva |
The self oscillating switching amplifier, although invented 30 or more years ago, was almost not known in the audio circles until UcD. Everybody was stuck with triangle wave generators until UcD appeared. Now there is a gworing number of companies that are either buying the ready-made UcD circuit from Hypex or developing their own self oscillating schemes.
I'm in the latter group. I was not aware of the advantages of self oscillating control loops until I read about UcD. Now, even International Rectifier is employing self oscillating control loops in their new class D devaluation boards. |
|
|
| Pabo |
Hi Eva
You are right about the benefits of self oscillating topologies. ICEpowers first modules where released a couple of years before the UcD patent application was filed by Philips in 2001. Their topology is also based on a self oscillating inner loop. |
|
|
| GDJ |
Speaking hypothetically Michael-Rifa, if your amplifier was bought and shipped to North America, run from a 220 volt source (which we have for our Electric Stoves, Clothes Dryers, Welders and Air Compressors in our garages, etc) would your amplifier be able to run with our 220 volt-40 amp-60 Hz AC power (single phase or three phase)?
Forgive me if I seem ignorant about your country's power supply. I'm asking because I am curious. |
|
|
| Michael-Rifa |
| Our amplifiers can work with any electric source from 150-260 Vac and of course can work in 50 or 60 Hz. So the answer to the last question is Yes, it will perfectly work on two phases of your electrical systen wich would be within the operating voltage and frequency range of the amplifier. |
|
|
| Michael-Rifa |
| Of course we can modify the power supply of the amplifier to work from 70-150 VAC. That vould be a costumized version but is very easy to do, and at no additional cost. |
|
|
|
