Enquiry about DIY Class D power amplifier

[alant4321]

Dear All,

I want to get information from experienced audio amateurs for building class D power amplifier. My goal is to build a fully balanced stereo (Dual mono) class D power amplifier using SMPS with output power at around 400W ~ 500W x2 / 8 ohm. I have the following choice of supplier:

1) Hypex UcD (Netherland): UcD700HG/HxR module + SMPS1200A700
2) Coldamp (Spain): Sonora S750 module + SPS80HV
3) CAD Audio (Denmark): D1000A PWM Amplifier + SW1000-45 SMPS
4) Audio Power (Italy): DXA-600 module + DPS-500S SMPS

Please comment which choice offers the best quality of sound?


B. regards,
alant

 

[GoranB]

Many people here are satisfied with Hypex, search for a thread.

 

[HiroPro]

I personally haven't heard this amp but if you read around it's been very well received in the community.

Class D Audio Home page

Of particular interest is the SDS-258 using IRS2092 from IR. It also is supposed to have a really good true differential input.

Also of interest is an SMPS from Italy. It's called the DPS-500-S from www.audiopower.it and the engineer behind that SPMS Roberto P does frequent this forum as does the designer/engineer for the SDS-258 IR based amps.

I have not heard either product but being a fly on the wall has allowed me to get a good idea of what's out there regarding a DIY amp. I've spend many hours of research and I feel SDS-258 with DPS-500-S is about the easiest to assemble and best deal around.

Expect performance that matches a $2k plus boutique piece.

All you need then is a good DSP with true differential outs and your set!!!

Sabre32 Reference DAC ES9018 perhaps !?!

With all the money saved buying the DIY amp you could pickup a W4S DAC-2 and perhaps even a STP-SE if you have the coin.

My ideal dream rig/transport/pre/amp would be:

PC-->W4S DAC-2-->W4S STP-SE-->SDS-258 with DPS-500-S SMPS.

Speakers would be something like Jed Kuntz's Duet10A with Air Circ 6620, Accuton C173 and Seas L26.

Pricetag on a rig like that is hardly Cheery and Cheerful but considering what some pay for "high-end" audio it's a bargain... And I honestly don't believe anything in the market could best it in performance either... At any price...

 

[alant4321]

Thank you for your information from HiroPro. Personally, I have heard the following DIY Class D power amplifiers from my friends previously:
1) Hypex UcD400AD + Coldamp SPS80 SMPS
2) Hypex UcD400HG + Linear power supply

Both options sound good as same detail in sound. But, SMPS provides more power reserve such as deeper bass capability when needed. For this reason, I prefer to use SMPS for the PSU of class D power amplifier.
It is no doubt that Hypex UcD is a good choice. But, the cost is the highest among all four choices above. Referring to the specification of the class D module as per their websites, they are all very similar and close. But, the most reliable result is actual listening test. For this reason, I would like to get more comments from other audio amateurs who have made or listened to other class D power amplifier.

 

[HiroPro]

I can't agree more regarding SMPS. I've played around with cheaper Tripath amps using linear and SMPS. I found better performance using MW SMPS models S-350, SP-350, S-320 and SP-320. The SP-320 is the best of the MeanWell units. PFC and higher switching frequency pay off!!! From that experience I came to the DPS-500-S. I'd say it's gotta be one the best prefab SMPS on paper for the DIY community. No matter what amp you purchase I'd get that SMPS for sure...

PS I have heard comment regarding the IR and besting the Dutch/Philips Hypex stuff.

International Rectifier - Audio Reference Design Kits

IRS2092S is one of the best gate PWM drivers around!!!
https://ec.irf.com/v6/en/US/adirect/ir?cmd=catProductDetailFrame&productID=IRS2092SPBF

 

[alant4321]

It is no doubt that SMPS is superior to Linear power supply for PSU of hi-end audio power amplifier. For your reference:
1) Hypex UcD (Netherland): UcD700HG/HxR module + SMPS1200A700
=>Power output: 375W x2/ 8 ohm at cost of Euro 1,120
2) Coldamp (Spain): Sonora S750 module + SPS80HV
=>Power output: 400W x2/ 8 ohm at cost of Euro 670
3) CAD Audio (Denmark): D1000A PWM module + SW1000-45 SMPS
=>Power output: 500W x2/ 8 ohm at cost of Euro 518
4) Audio Power (Italy): DXA-600 module + DPS-500S SMPS
=>Power output: 300W x2/ 8 ohm at cost of Euro 676

It is subject to individual preference. Priority is based on one of the following index:
1) Price (P) index: Low price first strategy
2) Price/Performance (P/P’) index: A balance between price and performance in quality of sound
3) Performance in quality of sound (P’) index: The best quality if sound first strategy

 

[alant4321]

A short notes of my viewpoint for the captioned four suppliers to share:

Hypex UcD from Netherland:Is it the market leader in supplier of class D DIY kit? My answer is “yes” in term of pricing, the highest price in the DIY audio industry, but not sure about its quantity sold to customer in term of annual sales revenue. The PWM module is well developed and gain reputation in the DIY audio industry, particularly in this DiyAudio forum. The SMPS module is recently developed and is subject to further comments.

Coldamp from Spain:It has recently developed a new Sonora series of PWM module which makes improvement in sound quality, reliability, efficiency and cost effectiveness for substituting old BP4078 PWM module and claims to be high performance in comparing to any competitors in the market. The SMPS module is well developed and I have practical experience with SPS80 with good reputation.

CAD Audio in Denmark:I have no practical experience and paper work review in this supplier. It is one of suppliers to companies such as B & O, Harris, Tripath, etc… which shows reliability in quality of product. But, the pricing is the lowest among the four.

Audio Power in Italy:I have no practical experience and paper work review in this supplier. The PWM module of DXA-600 is sold out presently which slightly reflects its reputation in consumer behavior. The SMPS module of DPS-500S received good reputation as per DIY audio amateur HiroPro in thread #3 & #5.

 

[luka]

while all could be good, I only know what I read, and that place still goes to Hypex

 

[ssanmor]

If you allow me, I would suggest that you also have a look at this combination from Coldamp:

2 x Sonora 2S300, each one bridged so you can get 2x500W+ at 8 or 4 ohm. All is integrated (PSU + 2 channels per module) and you don't require anything else. If at some moment you need 4 channels or stereo biamp, you already have the hardware.

The retail price for 2 units is 626 euro + 18% VAT + shipping, but you get 4 channels if you need them, instead of two, and you can even feed a smaller amplifier (such S250) from each module if you don't need the full power.

You would get full tech. support and connections verification service by us (by means of photos), this is very valued by our customers.

 

[alant4321]

If you allow me, I would suggest that you also have a look at this combination from Coldamp:

2 x Sonora 2S300, each one bridged so you can get 2x500W+ at 8 or 4 ohm. All is integrated (PSU + 2 channels per module) and you don't require anything else. If at some moment you need 4 channels or stereo biamp, you already have the hardware.

The retail price for 2 units is 626 euro + 18% VAT + shipping, but you get 4 channels if you need them, instead of two, and you can even feed a smaller amplifier (such S250) from each module if you don't need the full power.

You would get full tech. support and connections verification service by us (by means of photos), this is very valued by our customers.

Dear Ssanmor,

Thank you for your advice. Please note the two options as below:
My Option #1: 2x Sonora S750 PWM module + 2x SPS80HV SMPS
Your Option #2: 2x Sonora Combo 2S300 bridged PWM module with built-in SMPS

The total price for Option#1 and Option #2 are Euro 670 and Euro 626 respectively. The total output power in Watt x2/ 8 ohm for Option #1 and Option #2 are 400W and 500W respectively. Hence, Option #2 is cheaper than Option #1 by Euro 44, but higher power output by 100W per channel.
Personally, it is not significant in application and my major concern is the difference in both THD+N and S/N ratio. In other word, which option will provide better quality of sound? If both options are same in term of quality of sound, then it is no doubt to go for Option #2. Please advice.

 

[ssanmor]

In fact for that power level I would choose the option #2 in terms of sound quality even if you never need the extra channels, because the amplifiers work in bridge mode, that is better for the PSU as it automatically cancels bus-pumping that may occur to some extent with high power, low frequency with single-ended amplifiers such as S750.

 

[alant4321]

In fact for that power level I would choose the option #2 in terms of sound quality even if you never need the extra channels, because the amplifiers work in bridge mode, that is better for the PSU as it automatically cancels bus-pumping that may occur to some extent with high power, low frequency with single-ended amplifiers such as S750.

Noted and thank you for your advice.

 

[HiroPro]

alant4321 I would take a second look and read/ask opinion on the IRS2092/S based amps.

http://www.diyaudio.com/forums/class-d/116056-class-d-amp-irs2092.html

 

[alant4321]

alant4321 I would take a second look and read/ask opinion on the IRS2092/S based amps.

http://www.diyaudio.com/forums/class-d/116056-class-d-amp-irs2092.html

Dear HiroPro,

I am a Canadian who lives in Vancouver, but sometimes in Toronto with other relatives. Where do you stay in Canada?

In considering class D power amplifier using IRS2092, I take a look into SDS-258 PWM module from “Class D Audio” in USA. There is no detail specification from website, just state the specification as follows: “Output: 250W x2/ 8 ohm, THD+N, 1W at 1 KHz: better than 0.02% • Dynamic Range: 101 db • Efficiency: Over 90%. The price is US$ 260 per unit. From the website, I cannot see that it uses IRS2092, just you told me so. You suggest to use SDS-258 as PWM module from USA with DPS-500S SMPS from Italy. As per my requested output power at around 500W x2/ 8 ohm, it requires bridging two SDS-258 plus separated SMPS with total cost of US$ 487 (Euro 345). It is not cheap. It is also paper work discussion because I think that you have not heard this system yet. Haven’t you?

As per thread #3, your ideal dream configuration as below:
PC-->W4S DAC-2-->W4S STP-SE-->SDS-258 with DPS-500-S SMPS-> Speaker Jed Kuntz

My dream configuration is:
PC-->cone Pass Labs D1 DAC -->cone Pass Labs X2 pre-amplifier-->Class D Power amplifier-->speaker Focus Audio FS-888

I like pre-amplifier from Pass Labs and class D power amplifier from Jeff Rowland both in USA and Focus Audio speaker from Canada. I also adopt the ultra-symmetry fully balanced concept from Pass Labs or Jeff Rowland in my HiFi system.
I have considered B&O Icepower 1000ASP class D PWM module with built-in SMPS which is also used in Jeff Rowland power amplifier. But, I rejected because:
1) Jeff Rowland = Icepower 1000ASP PWM module + Lundahl LL7902. It is technical incapability for me to DIY such stuff to have similar performance with Jeff Rowland.
2) The cost is not cheap in buying both Icepower and Lundahl

 

[alant4321]

Sorry for typo error: total cost of US$ 487 (Euro 345) should read US$ 974 (Euro 690) because forgot to double the price due to bridged mode.

 

[HiroPro]

I'm curious why you need so much power? I can see a huge badass line array/columns of the Roger Russel flavor need that kind of power... What speakers are you going to be using?

 

[alant4321]

I'm curious why you need so much power? I can see a huge badass line array/columns of the Roger Russel flavor need that kind of power... What speakers are you going to be using?

In my HiFi system, all are ready to me except the class D power amplifier. Excess power does not mean bad, it is subject to individual preference with better control and stability to push the speaker plus the afordibility to pay additional cost. The speaker is Focus Audio FS-888 in Canada, an old version not selling now, but with very famous and good speaker unit, tweeter Scan-speak 9900 and woofer Eton 7-372Hex. Excess power can be for future upgrade to different speaker, such as speaker Avalon which is noramlly used to match with Jeff Rowland Continuum 500, class D amplifier with output power 500W x2/ 8 ohm.

 

[ssanmor]

I spent a month last year in Vancouver, preparing audio systems for the Olympics. Great city! I loved it.

 

[HiroPro]

One of the great things about the classdaudio module is that it can be bridged. I'd start with the SDS-254 and if you need more power latter you can bridge the unit. This is what I intend to do. I'm going to start with an amp/chassis with two SDS-254 non bridged x 4 chan. This way I can simply open up the chassis and wire them into bridge mode when I need 500W at 8ohms x 2 chan. Whenever I take delivery of a 10k+ line array... LOL

PS No matter what module you end up with I'd still consider the Roberto P's DPS-500-S due to it's dual feedback regulation and 150khz half bridge design. It should be VERY CLEAN and NOISE FREE. This is critical for class d due to low PSRR and low RFI/EMI induction that's inherent in class d amplifiers.

 

[HiroPro]

Another thing worth noting is class D running cooler, better and more efficient when driven. When they run low current IE low volume them tend to heat up but when driven they cool down. What is the sensitivity of those Focus Audio FS-888 speakers? If you run 500W plus on a module you just might find that you can't set the volume very high, perhaps 30%, to hear ear splitting SPL levels. You'd be much better off with less power thus running PWM driver cooler etc. I know it's the opposite of older technology but that's the deal with class d. I'd also choice SDS-254 because it can run at lower impedance than the SDS-258. I know a lot of what I'm saying is speculation regarding these product because I don't have either the amp or SMPS in house. I will though very soon and I'll share my experiences with everyone here. This is the rig I'm going to be building within the next month.

PC-->Audio-gd NFB-10WM Dac/Pre-->SDS-254 with DPS-500-S--> Dynamic 4T

I could never afford the Wired4Sound stuff but that NFB-10WM will give me relay stepped attenuator with dual WM8741 DAC and Kingwa's ACSS output.

Amp will cost about $800 bucks, The NFB-10WM is $800 bucks and the speaker kit from Jed Kunz is $1200 bucks. For three grand I should have a fantastic two channel rig. Same cost as Wyred4sound DAC2 and that stepped relay attenuator pre alone! Plus I think I prefer the WM8741 over the clinical Sabre32.

The results should be "Smooth" and very "Dynamic" !!!

PSS Have any of you heard the Tangband W4-1337 as a mid? OMG can it do mid... FABULOUS to use as a mid range!!!