Folsom's great little 7297 Chip Amp

Folsom · « **Reply #200 on:** 5 Mar 2016, 06:57 am »

For some reason my paint program isn't doing yellow... or something. I'm going to reinstall it. I've got a few requests for this,

Mmaxed · « **Reply #201 on:** 5 Mar 2016, 05:12 pm »

Thanks Jeremy, confirms everything. I have the amp running o batteries, need to get some kind of enclosure for the PS.

Is the Antipole capable of powering more than one amp?

Folsom · « **Reply #202 on:** 5 Mar 2016, 05:31 pm »

It can, yes.

BRN · « **Reply #203 on:** 5 Mar 2016, 07:23 pm »

Jeremy,

I received about 95% of the parts. Still waiting on wire and a power switch. I still need to decide on an enclosure, but I'm leaning towards your recommendation, Landfall Systems. I just need to do some measurements to see what size works.

I did have one question concerning the Bourns Common Mode Filters. I installed it with the part number facing toward the inside, caps and regulators. I thought that this way would provide the best results, because the wires leaving the coil have the shortest distance back to the board. If it is better to install it the other way please let me know and I will change it.

Thanks,
Brad

Folsom · « **Reply #204 on:** 5 Mar 2016, 07:28 pm »

I doubt it matters on direction.

lacro · « **Reply #205 on:** 5 Mar 2016, 08:28 pm »

Question about thermal paste:
Which type is best for this application, Metal based, ceramic based or carbon based? Is it critical that the paste is non electrically conductive given that the mica sheet is between the heatsink and the chip? In others words does it not matter which type compound is used because the mica sheet is the insulator?

Folsom · « **Reply #206 on:** 5 Mar 2016, 10:02 pm »

I would use non-conductive because it likes to get all over. Pretty much anything will do. I've got a small collection from PC building/fixing so I just use those.

Odal3 · « **Reply #207 on:** 6 Mar 2016, 06:31 am »

We are finally live! And yes, this amp is really really good. I will listen for a couple of days before doing a proper writeup. Once I had all the parts, it didn't take too long to put it all together.

Not sure about all of you, but every time I turn on something new for the first time, I'm holding my breath hoping for the best. Had a moment of panic when I only had sound in the left speaker, but it turned out it was just a loose IC between source and DAC.

I was listening to a TPA3116 amp (unmodded audiobah board, green) with an Astron while putting it all together. It was a very obvious change when I replaced it with the Folsom amp: Bass is lower and more detailed which is a big plus in my book.

Other first impressions was the clarity and the strong stereo image.

I don't have a case for it yet so it is still on the test setup. Btw: wired up all the signal connections with zenwave wire. Highly recommended.

lacro · « **Reply #208 on:** 6 Mar 2016, 03:32 pm »

Quote from: Odal3 on 6 Mar 2016, 06:31 am

We are finally live! And yes, this amp is really really good. I will listen for a couple of days before doing a proper writeup. Once I had all the parts, it didn't take too long to put it all together.

Not sure about all of you, but every time I turn on something new for the first time, I'm holding my breath hoping for the best. Had a moment of panic when I only had sound in the left speaker, but it turned out it was just a loose IC between source and DAC.

I was listening to a TPA3116 amp (unmodded audiobah board, green) with an Astron while putting it all together. It was a very obvious change when I replaced it with the Folsom amp: Bass is lower and more detailed which is a big plus in my book.

Other first impressions was the clarity and the strong stereo image.

I don't have a case for it yet so it is still on the test setup. Btw: wired up all the signal connections with zenwave wire. Highly recommended.

Good for you man

Glad to hear there is no smoke

What are using for a PS? BTW/ "a picture is worth a thousand words"

Odal3 · « **Reply #209 on:** 6 Mar 2016, 04:12 pm »

Picture...well...if I make it out of focus and blur it even more in photoshop one can maybe with a little bit of a stretch say my soldering efforts looks about the same as in the picture you or Folsom posted

I will put something up once I get around to it.

I'm using the same Astron PSU I have been using for the TPA3116. I wanted to make sure I could actually finish the amp before taking on too much (according to my wife, my basement is already full of unfinished projects of all kinds

). I think I'm now ready to take on the next project, which maybe will be the PSU Folsom is offering. However, what I really need now is to upgrade my DAC. Any suggestions of DIY or fully assembled DAC boards out there (Has to be somewhat easy to put together and preferably multi-channel so I can use it for DSP)?

maty · « **Reply #210 on:** 6 Mar 2016, 04:33 pm »

Maybe is a good idea add an IEC inlet like: RFI/EMI Schaffner FN9244B 1A.

-> http://www2.mouser.com/ProductDetail/Schaffner/FN9244B-1-06/

Datasheet: http://www.farnell.com/datasheets/1563480.pdf

BIG image -> http://maty.galeon.com/WP-imagenes/hard/IEC-inlet-filter-Schaffner-FN_9244-specs.png

BIG image -> http://maty.galeon.com/WP-imagenes/hard/IEC-inlet-filter-Schaffner-FN_9244-typical-filter-attenuation.png

Or you can add it after, building a cable with and IEC C13 connector (I "love" Schurter). Careful not to reverse the phase!

IEC C13 at Mouser -> http://www2.mouser.com/All-Manufacturers/_/N-0?Keyword=iec+c13

HAL · « **Reply #211 on:** 6 Mar 2016, 04:36 pm »

You might look for a Wolfson Micro (now Cirrus Logic) WM8741 based DAC.

The DAC Gary use to build with that IC, sounded really good at Danny's with the amps.

annamarykahn · « **Reply #212 on:** 6 Mar 2016, 05:24 pm »

Quote from: maty on 6 Mar 2016, 04:33 pm

Maybe is a good idea add a IEC inlect like: RFI/EMI Schaffner FN9244B 1A.

-> http://www2.mouser.com/ProductDetail/Schaffner/FN9244B-1-06/

Datasheet: http://www.farnell.com/datasheets/1563480.pdf

BIG image -> http://maty.galeon.com/WP-imagenes/hard/IEC-inlet-filter-Schaffner-FN_9244-specs.png

BIG image -> http://maty.galeon.com/WP-imagenes/hard/IEC-inlet-filter-Schaffner-FN_9244-typical-filter-attenuation.png

Or you can add it after, building a cable with and IEC C13 connector (I "love" Schurter). Careful not to reverse the phase!

IEC C13 at Mouser -> http://www2.mouser.com/All-Manufacturers/_/N-0?Keyword=iec+c13

i got a TE Connectivity / Corcom AC Power Entry Modules 15A FILTERED FLANGE MOUNT that i was going to try out

http://www.mouser.com/Search/ProductDetail.aspx?R=15CUFE1virtualkey59210000virtualkey592-15CUFE1

Folsom · « **Reply #213 on:** 6 Mar 2016, 07:07 pm »

I highly recommend not using those filter IEC inputs; they ruin sound. If you want an input filter contact me.

jtwrace · « **Reply #214 on:** 6 Mar 2016, 07:14 pm »

Quote from: Folsom on 6 Mar 2016, 07:07 pm

I highly recommend not using those filter IEC inputs; they ruin sound. If you want an input filter contact me.

Does a fuse ruin the sound and that's why you've omitted that?

maty · « **Reply #215 on:** 6 Mar 2016, 07:36 pm »

It is only one stage filter.

Devialet D200

NuPrime IDA-8

Double stage? NuPrime IDA-16

Folsom · « **Reply #216 on:** 6 Mar 2016, 07:45 pm »

Quote from: jtwrace on 6 Mar 2016, 07:14 pm

Does a fuse ruin the sound and that's why you've omitted that?

Audiophile grade ones work better, but if you want a fuse add one.

Folsom · « **Reply #217 on:** 6 Mar 2016, 07:49 pm »

Quote from: maty on 6 Mar 2016, 07:36 pm

It is only one stage filter.

My recommendation is what it is, and just because other types of equipment use them doesn't mean I endorse them nor believe those wouldn't sound better without them.

jtwrace · « **Reply #218 on:** 6 Mar 2016, 07:50 pm »

Quote from: Folsom on 6 Mar 2016, 07:45 pm

Audiophile grade ones work better, but if you want a fuse add one.

So are you saying that in your opinion it's not a requirement to have a fuse?

maty · « **Reply #219 on:** 6 Mar 2016, 07:51 pm »

Hypex (SMPS) has a good RFI/EMI filter inside. Maybe a Schaffner filter ruin the sound.

What RFI/EMI filter incorporates your design?