$175 Class D amp--120 wpc

kingnubian · « **Reply #1940 on:** 9 Sep 2010, 05:10 am »

Quote from: Barry_NJ on 9 Sep 2010, 03:57 am

Here's a few general, but related questions...

How did you go about buying your Class-D Audio amplifier?
Did you just go to the web-site, load your cart and check-out?
Or was there an email or telephone exchange before you decided which amp to purchase?

Buying a Class-D amp really IMHO involves two initial steps, reading & purchasing. Audiocircle is an amazing resource for Class-D info as is DiyAudio and will be very valuable as you gather more information leading up to your purchase.

In my case I "lurked" in forums for weeks soaking up as much info as possible on what was available finally officially joining a few. I settled on the SDS-254 from ClasDaudio.com and after that the purchase was just like any online purchase that I've ever made. Add to the cart & checkout. I did ask a few questions from the people from ClassDaudio.com but after all the reading I had done, my questions were mostly answered in advance.

If you finally decide to purchase a kit or completed product from the likes of 41hz, ClassDaudio, Hifimediy, Connex or whoever it's really a simple process.

avionic · « **Reply #1941 on:** 9 Sep 2010, 06:28 am »

Same as Kingnubian, got as much info as I could from diff. forums and then emailed Tom at ClassDaudio several times with any questions. Tom responds very quickly and is a straight shooter.

Barry_NJ · « **Reply #1942 on:** 9 Sep 2010, 04:44 pm »

Well I've been reading here, and at DIYAudio for quite some time. I've even had a CDA-224 that someone else had assembled to try for a bit, but it had a pretty bad hum in my system so I didn't really get a good feel for its sound, and I didn't want to disassemble and reassemble my friends amp to see if I could eliminate the hum. But I think I'm getting closer to finally pulling the trigger on one of these.

atterbud · « **Reply #1943 on:** 9 Sep 2010, 05:41 pm »

Quote from: avionic on 6 Sep 2010, 09:11 pm

I have been searching for an SMPS for the Class D audio amps for a while and finally found one. http://connexelectronic.com/product_info.php/products_id/118?osCsid=b0fbhen2sto5c1euaf4vrp4h02

Hooked it up to my CDA-254 and it sounds amazing. Even better than my modded linear power supply with 6x6800uf 63volt caps. The main reason I wanted the SMPS500R was because of the size. It is about 4"x4" , so now a reasonably sized 5 or 7 channel Class D audio amp is possible. Cristi the owner of connexelectronics is very helpful and makes a great product. Highly recommend

Hi Avionic
I am about to order a couple of the SDS-254 boards from ClassDAudio and had planned to power them from a pair of connexectronic A1000SMPS modules. I plan to run the boards in bridged mode and have contacted both Tom and at ClassD and Cristi at connex and both have confirmed that the modules will work well together. I wonder if you could comment a little more on how/why you chose the SMPS500R and how easy (or hard) it was to setup and wire up the modules. Did you have to make any special requests to either Tom or Cristi when you ordered the modules? Also if you have any experience with a linear supply with these modules, can you offer any further sound quality comparison between the two. Finally, I wonder if you could post some pictures of your implementation (especially of the wiring!).

Thanks very much for any help or advice you can offer.
Regards,Dave.

ichillpill · « **Reply #1944 on:** 9 Sep 2010, 05:50 pm »

If you know which amp to get it's as easy as loading your cart, and if you have a special request, I believe there is a "message to seller" field before confirming your purchase. Tom got mine out within 2 days.

Quote from: Barry_NJ on 9 Sep 2010, 03:57 am

Here's a few general, but related questions...

How did you go about buying your Class-D Audio amplifier?
Did you just go to the web-site, load your cart and check-out?
Or was there an email or telephone exchange before you decided which amp to purchase?

kingnubian · « **Reply #1945 on:** 10 Sep 2010, 03:55 am »

I want to add an On/Off switch to my SDS-254 (Front panel mounted).
I've looked over ClassDAudio's manual and know that a simple external SPST type switch can be added. My question is what spec of switch is supported with respect to voltage ratings, ect?

I'm looking at something like these:

http://www.surplustraders.net/specs/gd261.php

http://www.frozencpu.com/products/8735/ele-397/Blue_Illuminated_Bulgin_Style_Latching_Vandal_Switch_-_16mm_-_Black_Housing_-_Ring_Illumination.html?tl=g52c343s894#blank

http://www.frozencpu.com/cat/l3/g52/c343/s894/list/p1/Switches-16mm_Bulgin_Style_Switches-16mm_Latching_Bulgin_Switches-Page1.html?id=g8LV4JFH

Can these type of switches be used?

avionic · « **Reply #1946 on:** 10 Sep 2010, 06:33 am »

Hey Dave(atterbud) I sent you a PM.

raindance · « **Reply #1947 on:** 10 Sep 2010, 10:43 am »

Quote from: kingnubian on 10 Sep 2010, 03:55 am

I want to add an On/Off switch to my SDS-254 (Front panel mounted).
I've looked over ClassDAudio's manual and know that a simple external SPST type switch can be added. My question is what spec of switch is supported with respect to voltage ratings, ect?

I'm looking at something like these:

http://www.surplustraders.net/specs/gd261.php

http://www.frozencpu.com/products/8735/ele-397/Blue_Illuminated_Bulgin_Style_Latching_Vandal_Switch_-_16mm_-_Black_Housing_-_Ring_Illumination.html?tl=g52c343s894#blank

http://www.frozencpu.com/cat/l3/g52/c343/s894/list/p1/Switches-16mm_Bulgin_Style_Switches-16mm_Latching_Bulgin_Switches-Page1.html?id=g8LV4JFH

Can these type of switches be used?

The switch is telling the housekeeping circuit to turn the amp on, so it doesn't need to handle high voltage or current. Any single pole single throw switch will work provided it is latching. Also, the amp turns on when the switch is in the "off" position, which some may find odd.

hottuner · « **Reply #1948 on:** 10 Sep 2010, 11:06 am »

Quote from: avionic on 10 Sep 2010, 06:33 am

Hey Dave(atterbud) I sent you a PM.

I second atterbud's curiosity. I would like to hear your thinking too

kingnubian · « **Reply #1949 on:** 10 Sep 2010, 02:11 pm »

Quote from: raindance on 10 Sep 2010, 10:43 am

The switch is telling the housekeeping circuit to turn the amp on, so it doesn't need to handle high voltage or current. Any single pole single throw switch will work provided it is latching. Also, the amp turns on when the switch is in the "off" position, which some may find odd.

Thanks for the info!

And yes I find that odd. For a lighted switch it would mean that the led would be off for the amp to be on................very odd for sure.

raindance · « **Reply #1950 on:** 10 Sep 2010, 03:48 pm »

For power indication you'll need to add the external LED's that are provided for on the amp board. Don't rely on a lighted switch.

Feanor · « **Reply #1951 on:** 10 Sep 2010, 04:37 pm »

Quote from: raindance on 10 Sep 2010, 03:48 pm

For power indication you'll need to add the external LED's that are provided for on the amp board. Don't rely on a lighted switch.

Do you happen to know the specification for the LEDs? Do they need a resistor in series or anything like that?

Personally at the moment I'm just using a simple, 115V SPST ahead of the transfomer.

kingnubian · « **Reply #1952 on:** 10 Sep 2010, 04:56 pm »

Quote from: raindance on 10 Sep 2010, 03:48 pm

For power indication you'll need to add the external LED's that are provided for on the amp board. Don't rely on a lighted switch.

Thanks again.

Could I not just wire the switch's LED to the LED headers on the amp board?

raindance · « **Reply #1953 on:** 10 Sep 2010, 05:51 pm »

On my board and in the manual there are pads allocated for external LED's. I assume there are current limiting resistors in place already, but found it confusing that the manual specified colors for the LED's... Personally I am going to use red and amber (red for housekeeping circuit powered and amber for amps powered. Once I get this done I'll be able to say whether the connections are current limited or not.

I also have a power switch for the AC before the transformer, but prefer to let the housekeeping cicuit start up before applying power to the amp section so that I'm sure the unit is stable before it connects to my speakers. So I have two stage power. "Standby" and "On" from the front panel only, mains switching on the rear panel. THis also helps because I have an op-amp buffer that needs to charge it's output cap before the power amp comes online to avoid destroying my speakers. The same would happen (only worse) with a tube buffer.

Barry_NJ · « **Reply #1954 on:** 10 Sep 2010, 06:39 pm »

Would someone please post the measurements of the Power-Supply and SDS boards.
The CDA board is listed as 4.25" x 4.5" on the Class-D Audio web site, but I couldn't find measurements for the other boards.

Thanks, Barry

raindance · « **Reply #1955 on:** 10 Sep 2010, 07:04 pm »

Email Tom. He is very responsive.

srb · « **Reply #1956 on:** 10 Sep 2010, 07:35 pm »

Quote from: Barry_NJ on 10 Sep 2010, 06:39 pm

Would someone please post the measurements of the Power-Supply and SDS boards.
The CDA board is listed as 4.25" x 4.5" on the Class-D Audio web site, but I couldn't find measurements for the other boards.

I can't figure out why all of the board and transformer dimensions as well as the SDS manuals are not on the website. Is it really more time efficient to individually and repeatedly answer the same email inquiries over and over again than to post the missing information on the website?

I'll answer my own question. No, it's not. It's a lot more time consuming.

Steve

jtwrace · « **Reply #1957 on:** 10 Sep 2010, 07:50 pm »

...or you can do what I did...purchase one of each and make a solid CAD model.

raindance · « **Reply #1958 on:** 10 Sep 2010, 07:59 pm »

If you can wait for the weekend, I'll take some measurements on mine and put them on here. I'll take some photos too.

I've heard a few people have grounding issues, so I'll also post some detail on grounding.

Barry_NJ · « **Reply #1959 on:** 10 Sep 2010, 08:29 pm »

Quote from: raindance on 10 Sep 2010, 07:59 pm

If you can wait for the weekend, I'll take some measurements on mine and put them on here. I'll take some photos too.

I've heard a few people have grounding issues, so I'll also post some detail on grounding.

Excellent, thanks!