[jtwrace]

... ok, you got me!  On that note, maybe I should withdraw my question before I get run out of here. 

   You're welcome here!    

[krikor]

Well, I sold enough old stuff in the AKFest swap room last weekend that I can now try out one of these amp kits.  Looking at the SDS-224 but wondering what the extra $100 over the CDA-224 gets you besides balance inputs and adjustable gain.  In other words, sound quality... is it better?  I don't think I've seen much comparison in this regard on this thread (perhaps I missed it).

From classdaudio:
"Our Super D Series amps provide more life-like imaging and sound stage, along with the beautiful smooth tube-like sound we're known for. These amps are powerful, clean, quiet , and transparent"

Additionally, do you have to use the balanced inputs to achieve that improvement?  That may not be an option for me in the near future, so no sense spending an extra 100 if I don't have to.

Thanks.

[Nick77]

Well, I sold enough old stuff in the AKFest swap room last weekend that I can now try out one of these amp kits.  Looking at the SDS-224 but wondering what the extra $100 over the CDA-224 gets you besides balance inputs and adjustable gain.  In other words, sound quality... is it better?  I don't think I've seen much comparison in this regard on this thread (perhaps I missed it).

From classdaudio:
"Our Super D Series amps provide more life-like imaging and sound stage, along with the beautiful smooth tube-like sound we're known for. These amps are powerful, clean, quiet , and transparent"

Additionally, do you have to use the balanced inputs to achieve that improvement?  That may not be an option for me in the near future, so no sense spending an extra 100 if I don't have to.

Thanks.

The beauty of the InGenus balanced input reciever is that the single ended user benifits from the technology also. Myself and a few others are using single ended inputs on the Super with great success. It is very transparent and worth the extra dough. 

[Plund]

Help educate me please as I upgrade my system.  I recently built a pair of GR Research transmission-line N3 speakers and they sound awesome, even though they are driven with my inexpensive Yamaha 5250 AV receiver.  Enter Cheap and Cheerful 120W ClassD amp...Is it critical these amps are used with a preamp/buffer or can my source (Ipod, Cd player) feed them directly?  The Dodd DIY buffer is on my wish list of upgrades, but it will need to patiently wait.

Pete

[jtwrace]

Is it critical these amps are used with a preamp/buffer or can my source (Ipod, Cd player) feed them directly?  The Dodd DIY buffer is on my wish list of upgrades, but it will need to patiently wait.

Pete

No sir.  You can easily use your ipod / Cdp until you save up for the fantastic Dodd Buffer.  You'll have no problems at all I don't think. 

[srb]

Is it critical these amps are used with a preamp/buffer or can my source (Ipod, Cd player) feed them directly?  The Dodd DIY buffer is on my wish list of upgrades, but it will need to patiently wait.

To connect your sources directly, your CD player would need to have its own internal volume control and the iPod would have to control the volume through its headphone output jack.
 
Your iPod will much sound better if you use its line out output available at the bottom dock connector, either with an iPod dock or an inexpensive dock to line out cable, than it will using the amplified headphone output.
 
Therefore I would recommend using your Yamaha AV receiver as a preamp (by connecting its Main L/R RCA preamp outputs to the Class D Audio amp), until you can afford a better preamp.
 
Steve
 
 

[roymail]

Therefore I would recommend using your Yamaha AV receiver as a preamp (by connecting its Main L/R RCA preamp outputs to the Class D Audio amp), until you can afford a better preamp.
Steve

I agree, use the preamp section of your receiver or get a good passive volume control.

Blair Lamphear, a well respected AC sponsor, stated that this amp works great with a passive attenuator.  The input impedance is 45K ohms which will work fine.  I've also talked with Tom about this as well.

[ebag4]

Is it critical these amps are used with a preamp/buffer or can my source (Ipod, Cd player) feed them directly?  The Dodd DIY buffer is on my wish list of upgrades, but it will need to patiently wait.

Pete

I ran my Havana DAC directly into my ClassD for a little over a month and it sounded very good, I used the MPD client software to control volume.  I then added the Dodd Buffer and everything about the sound went up a number of notches!   You should be able to use your iPod directly into the amp for the time being (not sure of the output impedence of the iPod but my DAC is 800 ohms which is greater than recommended and it worked fine), when possible I heartliy recommend the Dodd Buffer, it is outstanding and works great with the ClassD.

Best,
Ed

[Plund]

To connect your sources directly, your CD player would need to have its own internal volume control and the iPod would have to control the volume through its headphone output jack.
 
Your iPod will much sound better if you use its line out output available at the bottom dock connector, either with an iPod dock or an inexpensive dock to line out cable, than it will using the amplified headphone output.
 
Therefore I would recommend using your Yamaha AV receiver as a preamp (by connecting its Main L/R RCA preamp outputs to the Class D Audio amp), until you can afford a better preamp.
 
Steve

Thanks all for your answers.  It looks like my plan going forward is to build the class D amp...my Yamaha receiver will be relegated to preamp status.  I believe, as a preamp, this receiver could still facilitate its present job of 50/50 home theater and 2 channel listening.  Then, when I build the Dodd buffer..??  I understand the Dodd buffer has no gain so possibly it could sit between the Yamaha and the class D.   

Pete

[guest1632]

Thanks all for your answers.  It looks like my plan going forward is to build the class D amp...my Yamaha receiver will be relegated to preamp status.  I believe, as a preamp, this receiver could still facilitate its present job of 50/50 home theater and 2 channel listening.  Then, when I build the Dodd buffer..??  I understand the Dodd buffer has no gain so possibly it could sit between the Yamaha and the class D.   

Pete

If I have understood about these amps, the gain is set at about 32DB approximately  6DB higher than the "standard" amplifier gain. So you might either consider getting one of the Promitheus TVC with the latest generation of transformers, or just get the passive resistive type volume control. Of course, the other way to go is to ask Tom to put a toggle switch in there so you could just toggle from either the standard gain to max gain. It has two trimmers, and you would have to know for sure after turning each one if you have the channels matched successfully.

Ray

[jtwrace]

....or just get a Super D amp and have adjustable gain.  I use a Dodd Buffer and have no issues with any of the Class D amps.  I have all three IR, TI & Super D.

[ebag4]

....or just get a Super D amp and have adjustable gain.  I use a Dodd Buffer and have no issues with any of the Class D amps.  I have all three IR, TI & Super D.

Hey Jason, do you have a favorite of the three?  With or without the buffer?

Best,
Ed

[jtwrace]

Hey Jason, do you have a favorite of the three?  With or without the buffer?

Best,
Ed

In my opinion the IR and Super D are above the TI for full range speakers.  I wouldn't hesitate to use the TI for a sub or for entertaining purposes.  It's just a little harsh (top end) in my opinion. 

[ebag4]

In my opinion the IR and Super D are above the TI for full range speakers.  I wouldn't hesitate to use the TI for a sub or for entertaining purposes.  It's just a little harsh (top end) in my opinion.

Cool, thanks! Looks like I picked the right one first try  . 

Best,
Ed

[roymail]

In my opinion the IR and Super D are above the TI for full range speakers.

Jason, to your ears, is there a significant difference in the sound of the IR and Super D?

I ask this question as someone who won't be using the balanced inputs.  I know this has been asked before, but I wanted your take on it.  Thanks!

[jtwrace]

Jason, to your ears, is there a significant difference in the sound of the IR and Super D?

I ask this question as someone who won't be using the balanced inputs.  I know this has been asked before, but I wanted your take on it.  Thanks!

Define significant.

In my terms of significant, no, in most audiophiles terms yes. 

In my system using the Super D there is no change from using XLR or RCA.  The adjustable gain is really nice though...

[roymail]

Jason, all other things being equal, comparing the IR board to the Super D board, and using only the SET inputs, do you hear a significant difference?

I guess for me, significant means "enough difference to justify the additional expenditure."  I know that both amp boards sound very good.

Thanks for the help. 

[roymail]

In my system using the Super D there is no change from using XLR or RCA.

So does that mean that single ended inputs are equally as good as balanced, or that balanced inputs are no better than single ended?

Just trying to understand, not being picky or difficult. Let's try these options.

- too close to call, equally as good
- the difference is noticeable but not by much
- there's a significant difference
- no brainer
- other (your choice of words)

I appreciate your opinion, and for sharing your experience.

[guest1632]

So does that mean that single ended inputs are equally as good as balanced, or that balanced inputs are no better than single ended?

Just trying to understand, not being picky or difficult. Let's try these options.

- too close to call, equally as good
- the difference is noticeable but not by much
- there's a significant difference
- no brainer
- other (your choice of words)

I appreciate your opinion, and for sharing your experience.

Hi Roy,
Now that you have me slightly confused, lol, having the super D and the IR board side by side, if I were to walk in to the room, could I be able to pick out the Super D versus the IR board? Or is it just a matter of degrees here, like dusk to dark kinda thing. As far as balanced versus unbalanced goes, there would hardly be any real differences, so I would think, not enough to worry about.

Ray

[steve k]

So does that mean that single ended inputs are equally as good as balanced, or that balanced inputs are no better than single ended?

Just trying to understand, not being picky or difficult. Let's try these options.

- too close to call, equally as good
- the difference is noticeable but not by much
- there's a significant difference
- no brainer
- other (your choice of words)

I appreciate your opinion, and for sharing your experience.

Since I've had both, I'll throw my 2 cents in here. I would vote for "the difference is noticeable but not by much". The biggest difference I noticed is the Super D seems to throw out a deep

er soundstage (at least in my system) whereas the ClassD tended to be flatter in depth (more on a plane between the speaker).

Steve