Class D Audio, Who are these guys?

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#266
Hi, folks,

I'm just finishing up a SDS-258 contruction -- nothing fancy: no mods, just a plug and play. However a question: can I by-pass the supplied volume pots?

Tom at Class D Audio says, "Yes, you have to have the gain pots installed… you’ll like them, use them. It will let you adjust the gain of the amp to match the sweet spot of your preamp… usually between 9:00 and 2:00 position." He gave no further explanation.

Still, I think I'd rather by-pass them if possible. Can this be done easily, e.g. by jumping a couple of the header pins? If so, which ones? Or other simple options?

Your advice will be appreciated!
 
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#267
Feanor said:
Hi, folks,

Still, I think I'd rather by-pass them if possible. Can this be done easily, e.g. by jumping a couple of the header pins? If so, which ones? Or other simple options?

Your advice will be appreciated!
Click to expand...

I have an sds-224 that I haven't gotten to, and was wondering the same thing. Since a pot is just a resistive divider, it is possible to replicate a specific setting of the pot with fixed resistors. The question is whether this can be a simple resistor across the headers or whether it has to be a true divider. I haven't looked at the board and reference schematics closely enough to have any idea on that score yet, though.
Anyway, my general plan is to use the pots until I'm sure of my overall system setup, and then look at replacing them if necessary/possible. IMHO the concern isn't as much with the pot as much as the potential to pick up EMI on the leads; if I can keep the leads short enough, then it may be a moot point.
 
#269
ggetzoff said:
What does the manual say about the jumpers?
Click to expand...
As yet there is no manual. Tom admitted this in the brief instructions that accompanied the SDS; those instructions said nothing about the attenuator pots except how to solder the leads, nor about various other stuff different from the CDS models, e.g., the LED connections.

I will install the pots, at least until I get a better understanding.
 
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#270
I am about to pull the trigger on an SDS-254 (First build) and what's keeping me back is I would really rather, initially at least, like to use this kit in an Integrated Amp fashion.

Has anyone got theirs setup that way. If so, how was the volume pot wired & what additional components/setup was needed??
 
#271
Mr Allen,who are you? Where are you? I hope that you are okay.Just asking,because you are missing for almost 9 months.
After being so passionate about the ClassDAudio,suddenly nada.What happened to that amp shootout?
Are you okay?

I would like to be excused for my seemingly ironic tone,but it is ironic.Maybe the moderator of the site,will oust me for this,but its ok.

I read the "www.teamamericatech.com","parent" site of the Class D and so on co,that makes the assembly,as is written on the module,and proudly says that they are a non profit org,that helps those in need for honest work.And they accept donations too.Which is allright with me,and everyone else.
Such a movement has to be ADVERTISED,in every possible chance.Especially in the www,no?

But to my surprise,there is not a single mention of the connection,in EITHER site.

I think that most of us we are willing to pay an overhead,for our hobby,if it is for charity.
But they say nothing.Why?

Could you please Mr ALLEN , or Mr TOM enlighten us?


B.L.
 
#273
kingnubian said:
I am about to pull the trigger on an SDS-254 (First build) and what's keeping me back is I would really rather, initially at least, like to use this kit in an Integrated Amp fashion.

Has anyone got theirs setup that way. If so, how was the volume pot wired & what additional components/setup was needed??
Click to expand...

''If so, how was the volume pot wired & what additional components/setup was needed?? '' that's what I want to know
I have seen some attempts by Nick77 on the earlier pages( #240) of this thread
Nick77, could you inform us result of this attempt? and any ideas to do
 
#274
darkfury said:
''If so, how was the volume pot wired & what additional components/setup was needed?? '' that's what I want to know
I have seen some attempts by Nick77 on the earlier pages( #240) of this thread
Nick77, could you inform us result of this attempt? and any ideas to do
Click to expand...

The new SDS series has onboard adjustable gain already installed onboard as a new feature. Comes stock with molex connectors and gain pots. These are gain pots and not volume pots.

I know Tom can set the gain to a specific requested setting before shipping on the first series, you might contact him. I dont know if adjustable is an option or not.

I built a Pass B1 buffer for volume control and its a great match up to the class d amp.
 
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#275
Nick77 said:
The new SDS series has onboard adjustable gain already installed onboard as a new feature. Comes stock with molex connectors and gain pots. These are gain pots and not volume pots.

I know Tom can set the gain to a specific requested setting before shipping on the first series, you might contact him. I dont know if adjustable is an option or not.

I built a Pass B1 buffer for volume control and its a great match up to the class d amp.
Click to expand...

I got this email from Tom:

---------------------------------------------------------

"Hi xxxxxx,

Yes, it's possible to use a ganged volume pot on the amp. The SDS comes with 2 high quality gain controls you can use as volume control, so all you have to do is get a dual ganged pot... very easy.

I don't have time to draw up a diagram right now, but I can when I have more time.

Please let me know if I can be more help.

Thanks,
Tom"
----------------------------------------------------------

Now I don't know if I was clear when I said in the original email that I wanted to use the board as an Integrated Amp setup & the issues with using the gain as a volume control. I'll have to respond more clearly to him.

I have toyed with the idea of building a simple passive preamp (Using a better matched 10k pot & input selector) but I really want to get away from building another box at this moment. I was told a 10k pot would be a better match for the input impedance of the SDS-254.

I was thinking of just placing the Passive Preamp parts in the amp housing thereby creating an Integrated Amp by definition.

Is this doable??

Input-->Selector Switch-->Volume Knob-->Amp Input
 
#277
Hi, did anybody try to get in contact with classdaudio.com recently? I bought 3 modules TI-300 a year ago, but 1 is dead now. I wrote several mails starting in janurary, but did not get an answer. Is their service really that bad?
Best regards Martin from germany
 
#280
I guess it's a IRAudAmp7 IRS2092 ?

Considering SMPS from Roberto P (AP2 from audiopower.com Italy) model DPS-500-S with classdaudio.com SDS-258. I hear great things regarding SDS series amps!!!

Has anyone here used AP2 SMPS with SDS-258?

About to do a DIY 2 chan rig with the latest and greatest "Cheap and Cheerful"

Current list is:

Jed Kunz Dynamic 4T SE DIY towers
Emotiva XDA-1 DAC (also used as pre)
SDS-258 amp with DPS-500-S SMPS

Comments, hints and suggestions?
 
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