$175 Class D amp--120 wpc

Æ · « **Reply #2940 on:** 4 Dec 2011, 03:59 am »

Quote from: justinm on 4 Dec 2011, 01:42 am

Mine is still making the sound on shut off and a small pop when turned on. I hope it doesnt cause any damage to the amp, but the level of the sound is so low I just ignore it now.

You should try a small, maybe .1uF snubber capacitor across the On/Off switch, it should kill your turn on pop.
It wont hurt to experiment. Increase the uF if you are noticing it working at least to some extent and you'd like to have it working even some more. If there are no audible results, then simply remove the cap.

djklmnop · « **Reply #2941 on:** 4 Dec 2011, 10:33 am »

I finally put this bad boy together (CDA-254L). I notice most of you put your transformer with the wires on the bottom side, but it seems that the wires would be bearing all the weight. Is it 'supposed' to be at the bottom?

Preamp: IRD Purist
Source: Squeezebox

I played it for about 4 hours tonight. Right off the bat it was grainy, but it quickly smoothed out. After about an hour, the graininess went away, now it is all very smooth.. By the end of the session, the it sounded great! I cant wait to break this in some more.

Nick77 · « **Reply #2942 on:** 4 Dec 2011, 10:39 am »

Nice work!

Put a nice power cord on that and you will smile.

mboxler · « **Reply #2943 on:** 4 Dec 2011, 02:26 pm »

Quote from: djklmnop on 4 Dec 2011, 10:33 am

I finally put this bad boy together (CDA-254L). I notice most of you put your transformer with the wires on the bottom side, but it seems that the wires would be bearing all the weight. Is it 'supposed' to be at the bottom?

I wondered the same thing, so I e-mailed tech support at Antek. The answer was, it doesn't matter. If you go to their website (antekinc.com), you'll notice that they have their power supply transformers "upside down". The tech said that was done because it fit the case better. I have mine "upside down" 'cause it "sits" better with me.

Mike

ptempel · « **Reply #2944 on:** 4 Dec 2011, 03:55 pm »

Quote from: djklmnop on 4 Dec 2011, 10:33 am

I finally put this bad boy together (CDA-254L). I notice most of you put your transformer with the wires on the bottom side, but it seems that the wires would be bearing all the weight. Is it 'supposed' to be at the bottom?

Preamp: IRD Purist
Source: Squeezebox

I played it for about 4 hours tonight. Right off the bat it was grainy, but it quickly smoothed out. After about an hour, the graininess went away, now it is all very smooth.. By the end of the session, the it sounded great! I cant wait to break this in some more.

Well done. I agree with the others and don't think it matters which way the torroid goes. Two rubber pads usually come with it so they help to seat it and reduce vibration. I moticed the same "smoothing out" and am listening to it right now. Am amazed at the detail and control the amp has over the speakers. Only drawback with the Adcom GFP-555ii preamp is that it has too much gain. But that's ok for now since I'd like to try a passive buffer like the Dodd or Pass B1 at some point.

mboxler · « **Reply #2945 on:** 4 Dec 2011, 04:41 pm »

Thought I'd post my project. I'm bi-amping a pair of Klipshorns, and wanted to see if I could include everything in one case. This is a temporary setup, but so far so good. Includes an SDS-480 kit, and Marchand electronic crossovers (24db slope). Initially, had issues with Marchand's, in that they needed to be powered up BEFORE the amps, or I got a very loud transient POP. Solution was to use my old Monster Power Center. The amp power supply is plugged into a delayed switch outlet, and the Marchand PS into an immediate switch outlet. Now, the amps power on a few seconds after the Marchand PS, and power off a few seconds after the Marchand PS is powered off. I will not need power switches on the enclosure.

Mike

ptempel · « **Reply #2946 on:** 5 Dec 2011, 02:06 pm »

Quote from: mboxler on 4 Dec 2011, 04:41 pm

Thought I'd post my project. I'm bi-amping a pair of Klipshorns, and wanted to see if I could include everything in one case. This is a temporary setup, but so far so good. Includes an SDS-480 kit, and Marchand electronic crossovers (24db slope). Initially, had issues with Marchand's, in that they needed to be powered up BEFORE the amps, or I got a very loud transient POP. Solution was to use my old Monster Power Center. The amp power supply is plugged into a delayed switch outlet, and the Marchand PS into an immediate switch outlet. Now, the amps power on a few seconds after the Marchand PS, and power off a few seconds after the Marchand PS is powered off. I will not need power switches on the enclosure.

Nice crossovers. How much did they charge for each crossover? Any reason for not choosing a separate 1U or 2U case for them? I can see myself heading down this path. But would need another amp and different speakers before then. Also, are you using some sort of mic to measure the frequency response of your speakers?

Philippe

mboxler · « **Reply #2947 on:** 5 Dec 2011, 04:10 pm »

Quote from: ptempel on 5 Dec 2011, 02:06 pm

Nice crossovers. How much did they charge for each crossover? Any reason for not choosing a separate 1U or 2U case for them? I can see myself heading down this path. But would need another amp and different speakers before then. Also, are you using some sort of mic to measure the frequency response of your speakers?

Philippe

Thanks. The Ps is $50. Each crossover (mono) is $40. You can see more info at Marchandelec.com. Two XM1's cross at 400Hz, the other two at 40Hz. 400Hz and above to passive crossover, 40Hz to 400Hz to bass driver, 40Hz and below may someday go to subwoofer. Mounting everything in one case really simplified the wireing (no rca's to buy/solder/mount, no cables to connect). Just ran 16 AWG wires from crossovers to crossovers/amps (took less than an hour). I'm having a new passive mid-to-high crossovers built to custom match my drivers. Once they arrive, I'll work with the engineer to determine the best way to measure/adjust the bass gain to match the new passive crossovers, which he'll tune flat from 400Hz and above.

Mike

Adhara · « **Reply #2948 on:** 5 Dec 2011, 10:28 pm »

Hi,

Here below some pics of my SDS-470 amp that Tom made for me.

This amp has successfully replaced my old Nuforce MCH 300 SE (6k € pricing).
speed, tube sound, soundstage, lot of material in the voices ...

It's an amazing piece of gear !!

I'd like to compare it to Edge power amp but this US brand is not distributed here in France.
I know Edge uses hybrid model of Ice power modules. it seems perfectly sound (from what I can read).

Did you listen to Edge amp already (Edge G AV 5x250W for exemple) ? .... and compared it to classDaudio amps ?

I know the Edge GAV 5 is sold 11k € in Europe...

From my point of view, I find this is very expensive for a Ice Power unit ...

Thx for your feedback.

hulkss · « **Reply #2949 on:** 7 Dec 2011, 02:46 am »

Quote from: Adhara on 5 Dec 2011, 10:28 pm

Hi,
Here below some pics of my SDS-470 amp that Tom made for me.
Thx for your feedback.

That's a lot of powerful amplifiers for one power supply. What are you driving with it?

lanchile · « **Reply #2950 on:** 7 Dec 2011, 03:08 am »

Quote from: djklmnop on 4 Dec 2011, 10:33 am

I finally put this bad boy together (CDA-254L). I notice most of you put your transformer with the wires on the bottom side, but it seems that the wires would be bearing all the weight. Is it 'supposed' to be at the bottom?

Preamp: IRD Purist
Source: Squeezebox

I played it for about 4 hours tonight. Right off the bat it was grainy, but it quickly smoothed out. After about an hour, the graininess went away, now it is all very smooth.. By the end of the session, the it sounded great! I cant wait to break this in some more.

Well, if you use metal chassis (not in your case), you should put those ac voltages as close to the chassis as you can and also you should twist those wires as much as you can to avoid any hamming from ac voltages. metal chassis are used to ground deathly voltages and also to shield RF and anwanted noises.

Adhara · « **Reply #2951 on:** 7 Dec 2011, 05:48 pm »

Quote from: hulkss on 7 Dec 2011, 02:46 am

That's a lot of powerful amplifiers for one power supply. What are you driving with it?

Hi,

I made the same remark to Tom.
I successfuly drove with it Elac and Wislon Benesh speakers.
Here below what he answered to me.

Quote

your amp has more than enough power for music or home theater. This controversy over transformers and power supplies has been going on for years. This would be true if you were running a constant sine wave through all 6 channels, but music and movies is not a constant sine wave. The amps will actually only bee using about 1/8 power for this. If this amp had a 3KW power supply, it would be huge and just allot of wasted space and power. The only time the amp would need such a large power supply is for bench power testing… something only a manufacture would do. Also, our amplifiers are about 92% efficient and draw much less power form the wall than other types of amplifiers. I think when you listen to your amp, you’ll find you have more than enough power.

I trust him. He will never build and sell undersized power amps...
Since I receive this amp I had the opportunity to test it on Wilson Benesh Vertex speakers (outstanding product, by the way!!).
My ClassDaudio amp worked better than Sugden MPA-4 on Vertex and no lack of power (even at high volume).

hulkss · « **Reply #2952 on:** 8 Dec 2011, 04:01 am »

Quote from: Adhara on 7 Dec 2011, 05:48 pm

I trust him. He will never build and sell undersized power amps...

Like he said....it will be good for typical home use. You must tell Tom what you are doing with the amp.

If you told him you needed power for large subwoofers, each SDS-470 would get it's own transformer and power supply.

Adhara · « **Reply #2953 on:** 8 Dec 2011, 08:10 am »

Quote from: hulkss on 8 Dec 2011, 04:01 am

Like he said....it will be good for typical home use. You must tell Tom what you are doing with the amp.

If you told him you needed power for large subwoofers, each SDS-470 would get it's own transformer and power supply.

This amp is perfect to drive:

- 2.0 full range speakers (35 Hz - 20 kHz (100 Db at 16 ft)).
- 5.1 system (80 Hz - 20 kHz (100 Db at 16 ft)) – Sub Xover is set to 80 Hz.

My sub (Velodyne DD12) have its own power supply

matt_garman · « **Reply #2954 on:** 9 Dec 2011, 05:59 pm »

Quote from: matt_garman on 26 Oct 2011, 02:23 pm

On the power consumption front, I'm using an AC Watt meter (Kill-A-Watt). The SDS470 seems to pull about 22 Watts, both at idle (no music) and typical listening levels using the standard kit linear power supply. I haven't really cranked it up yet. Compared to the QSC, which pulled 40--60 Watts between idle and music. A definite improvement in power usage. As I suggested above, I'd like to get a switch-mode power supply (SMPS) to see if I can further reduce idle power consumption.

FWIW... I got my SMPS800R from Connexelectronic last week. Only last night did I finally have a bit of time to try it out.

The main thing I was going for was reduced power consumption through higher efficiency. I was a bit disappointed to see that the SMPS is actually a bit worse, at least at idle/low volume levels. Idle and low listening level AC power consumption was around 25 Watts.

The SMPS is definitely smaller than the linear PS's capacitor bank + transformer. I estimate that the SDS-470 and SMPS800R could fit together comfortably in a 6x12 enclosure, maybe even 6x10.

As for sound quality... too soon to tell. I only had time to set it up, then do basic testing. Definitely no obvious problems. If there are any SQ differences, they will be nuanced.

In my infinite wisdom and grace, I may have damaged one or more components: before connecting the SMPS800R to the SDS-470, I wanted to make sure the output DC voltage was correct (since it was a custom voltage request). And before that, I wanted to check the linear PS's voltage as a baseline reference. When using my DMM to check DC voltage on the linear power supply, I accidentally got the probes too close together and generated a nice arc! I was actually probing on the SDS-470, so the board got a nice burn mark right under the DC input receptacle, as did my DMM probes. In my brief listening period, the amp sounded fine, so I don't think I actually harmed it. Not sure about the linear power supply though, as I didn't have time to test it after the fact. But I didn't blow a fuse, and it was brief enough that I'm hoping no actual damage was done.

Be careful out there!

Æ · « **Reply #2955 on:** 9 Dec 2011, 08:24 pm »

Quote from: matt_garman on 9 Dec 2011, 05:59 pm

When using my DMM to check DC voltage on the linear power supply, I accidentally got the probes too close together and generated a nice arc!

Who hasn't? I did similarly once and took out several expensive power transistors. Oh well, live and learn.

poseidonsvoice · « **Reply #2956 on:** 9 Dec 2011, 09:23 pm »

Quote from: Adhara on 7 Dec 2011, 05:48 pm

Hi,

I made the same remark to Tom.
I successfuly drove with it Elac and Wislon Benesh speakers.
Here below what he answered to me.

I trust him. He will never build and sell undersized power amps...
Since I receive this amp I had the opportunity to test it on Wilson Benesh Vertex speakers (outstanding product, by the way!!).
My ClassDaudio amp worked better than Sugden MPA-4 on Vertex and no lack of power (even at high volume).

Very nice to see that the Class D amp has made it across the pond, and is being compared with very high priced competition! I remember Wilson Benesch from the 90's, I liked their Act 1 speaker.

Thanks for the review,

Anand.

steve k · « **Reply #2957 on:** 9 Dec 2011, 10:15 pm »

Indeed! We rarely see a great product at a great price in this hobby!

steve k

krikor · « **Reply #2958 on:** 11 Dec 2011, 10:12 pm »

FINALLY... got my SDS-450 monos up and running (balanced input only). However, after getting them connected and making wonderful music, one of the amps kept cutting out (yellow LEDs on) for a few seconds and then coming back on (blue LEDs back on). This started after about 10-15 minutes of play time on my Magnepan 1.6 speakers.

Cable swaps, channel swaps, etc. to verify it is due to something inside the amp... yep. Disconnect, open up, look for mis-wire... all looks proper. Check continuity of connectors... all OK. Check power supply output... +48.9, -48.7 (both amps measure the same).

Now I'm beginning to think its an overheating issue. Working longer now with the top off, thought I was in the clear, but then cutout again just now. Heat sinks on both amps are very warm to the touch, can't hold finger there longer than about 10 seconds... seems strange for an amp that is supposed to be OK down to 2 ohms in stereo and recommended by Tom for my Maggies. And just now the other amp cutout while checking the heatsink temp! Time to contact Tom... wonder if I got the wrong power supply or perhaps the wrong amp as I can't see anything on the board identifying it as a 450, 470, 258, etc.

Or could it be I need to keep right-channel jumper J2 in place when running it as a mono balanced amp? Doesn't seem likely.

Mono SDS-450 amps, balanced XLR input only, 4-pole SpeakOn connector for single-connector biwiring, PowerCon AC connector. Temporary mounting of gain pots until I settle on a fixed resistor value.

Internal bi-wire jumper to 4-pole SpeakOn connector... I don't think I'll ever use binding posts again on anything I build.

I.Greyhound Fan · « **Reply #2959 on:** 12 Dec 2011, 03:29 am »

I am about to order a Par Metal Case and I have a couple of questions about it.
Will the 16x12x4" case have enough height to fit the 400VA power transformer or will I need to go with a 5" tall case?

Also, did you guys go with Anodine or Anodized cases? Anodine is supposed to offer better EMI/RFI sheilding than Anodized according to the guy that I spoke to at Par Metal. The trade off is that Anodine scratches easier than Anodized. My CDA 254 (currently in a wooden box) gives off a lot of RFI, so much so that I can't use my tuner.

One last question, did you guy's go with the thicker front panel or just the .125" thick front panel which is standard? I am leaning to the thicker front panel.

Thanks,

Larry