Sure-Electronics.com class d amps - Page 4

buzz1939 · 16th November 2007, 09:47 PM

Not all connectors that look like that are the same size. However, the one this takes is one of the most common sizes.

And the package included a connector if you're willing to splice the wires to it. See the photos.

6A is plenty.

The 24V might be fine, the question might be how well regulated the power supply is, since voltage can fluctuate well above the stated voltage on some; and what the real max voltage on the amp. Personally, I'd try it, but ....

The most important thing - make sure the polarity is center positive. That's most common, but not always the case.

buzz1939 · 16th November 2007, 10:30 PM

fwiw the MP7782 spec sheet (if that's even what this is) shows an absolute max supply of 26V, up to 24V recommended.

h82missafire · 17th November 2007, 06:41 AM

Thank you! New to amp module building, so I greatly appreciate any feedback.

h82missafire · 17th November 2007, 06:41 AM

fwiw the MP7782 spec sheet (if that's even what this is) shows an absolute max supply of 26V, up to 24V recommended.

what would you suggest for amp and volt psu?
Thanks

MikeHunt79 · 17th November 2007, 03:49 PM

I've just ordered one of these, and am tempted to power it from a 12v SLA battery...

Would I get a higher power output with a 24v PSU (or 2 x 12v batteries in series)?

buzz1939 · 17th November 2007, 04:59 PM

I would think that more voltage = more gain. What the relationship is, and how it affects distortion, I wouldn't know. That is, is the max voltage also going to push you into an area where the distortion is more than you want?

I'd also appreciate hearing from someone who knows (ie, not me), because I'm wondering if one way to manage the hiss/noise on this would be to use lower voltage if I'm not needing all the gain it's capable of. Less gain would let me increase the signal (to achieve the same comfortable listening level) and hopefully improve the signal to noise.

I spent another half hour or so listening using a 14V supply. On a bad source it magnifies every flaw (eg, a desktop computer with a very good but inboard sound card that picks up a lot of noise). Other sources (eg, mp3 player) were pretty clean on some music, but less so on others. Haven't sorted that out yet - by comparing the original on other gear, for example.

Not sure if it would matter but - I have it hooked up as 2 channel, channels 1 and 4, haven't tried any other combination.

Noticed that I have version 1.1 of the board, not 1.0 as shown in the PDF. Only obvious difference I saw was that the output channels are re-ordered (1 is where 4 was).

MikeHunt79 · 18th November 2007, 02:31 PM

Quote:

Originally posted by buzz1939
[B]I would think that more voltage = more gain. What the relationship is, and how it affects distortion, I wouldn't know. That is, is the max voltage also going to push you into an area where the distortion is more than you want?

Thanks... I may pick up the 24V supply then...

I think 2x12v batteries in series would be a bad idea, as fully charged they are around 14v, and 14+14 = 28v, which is too much voltage for this amp...

I guess I could wire in 3 diodes in series with the power cable, which should give 2.1v voltage drop... but I think it would be much less hassle running it straight from the 24v PSU.

Running it from a 12v battery would be good for in the car tho, or even in a portable boombox... I guess class D is ideal for portable us as it's very efficient.

Anyway, I'm rambling on now, I just have a quick question about bridging this amp...

Say I'm powering 2 x 4 ohm subs, and wire them up so they are bridged, would I have to input a signal just on channels 1 & 3, or would I have to supply an input to all 4 channels?

theAnonymous1 · 18th November 2007, 05:44 PM

Quote:

Originally posted by theAnonymous1
It is already bridged, hence the single supply and two inductors per channel.

You might be able to parallel the channels for more current with low impedance loads.

h82missafire · 20th November 2007, 03:56 PM

Has anyone who has received one of the 'Sure' boards done any more testing or was able to get around the "hiss"?

Still waiting for mine to arrive.

Thanks

Bearman · 20th November 2007, 05:47 PM

Mine arrived today and at first sight, the board looks well made.

I did notice right off, that the bottom of the board needs to be cleaned. There is flux between solder points. I have had hum from flux before.

I'll try and hook it up tonight and see what we have.

17th November 2007, 06:41 AM	#33
h82missafire diyAudio Member Join Date: Sep 2007	6A is plenty. Thank you! New to amp module building, so I greatly appreciate any feedback.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
MM Electronics Paice amps???	burningbushhifi	Solid State	7	6th July 2011 01:46 PM
For Sale: Tube Amps, Class-A Amps, BG Ribbons, Chassis and Other Goodies!	opc	Swap Meet	23	2nd November 2009 05:04 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

16th November 2007, 09:47 PM	#31
buzz1939 diyAudio Member Join Date: May 2007	Not all connectors that look like that are the same size. However, the one this takes is one of the most common sizes. And the package included a connector if you're willing to splice the wires to it. See the photos. 6A is plenty. The 24V might be fine, the question might be how well regulated the power supply is, since voltage can fluctuate well above the stated voltage on some; and what the real max voltage on the amp. Personally, I'd try it, but .... The most important thing - make sure the polarity is center positive. That's most common, but not always the case.

16th November 2007, 10:30 PM	#32
buzz1939 diyAudio Member Join Date: May 2007	fwiw the MP7782 spec sheet (if that's even what this is) shows an absolute max supply of 26V, up to 24V recommended.

17th November 2007, 03:49 PM	#35
MikeHunt79 diyAudio Member Join Date: Aug 2003 Location: Bristol, UK	I've just ordered one of these, and am tempted to power it from a 12v SLA battery... Would I get a higher power output with a 24v PSU (or 2 x 12v batteries in series)?

17th November 2007, 04:59 PM	#36
buzz1939 diyAudio Member Join Date: May 2007	I would think that more voltage = more gain. What the relationship is, and how it affects distortion, I wouldn't know. That is, is the max voltage also going to push you into an area where the distortion is more than you want? I'd also appreciate hearing from someone who knows (ie, not me), because I'm wondering if one way to manage the hiss/noise on this would be to use lower voltage if I'm not needing all the gain it's capable of. Less gain would let me increase the signal (to achieve the same comfortable listening level) and hopefully improve the signal to noise. I spent another half hour or so listening using a 14V supply. On a bad source it magnifies every flaw (eg, a desktop computer with a very good but inboard sound card that picks up a lot of noise). Other sources (eg, mp3 player) were pretty clean on some music, but less so on others. Haven't sorted that out yet - by comparing the original on other gear, for example. Not sure if it would matter but - I have it hooked up as 2 channel, channels 1 and 4, haven't tried any other combination. Noticed that I have version 1.1 of the board, not 1.0 as shown in the PDF. Only obvious difference I saw was that the output channels are re-ordered (1 is where 4 was).

20th November 2007, 03:56 PM	#39
h82missafire diyAudio Member Join Date: Sep 2007	Has anyone who has received one of the 'Sure' boards done any more testing or was able to get around the "hiss"? Still waiting for mine to arrive. Thanks

20th November 2007, 05:47 PM	#40
Bearman diyAudio Member Join Date: Apr 2005 Location: Utah	Mine arrived today and at first sight, the board looks well made. I did notice right off, that the bottom of the board needs to be cleaned. There is flux between solder points. I have had hum from flux before. I'll try and hook it up tonight and see what we have.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)