How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

[TN Allen]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

Thank you for the offer, but I want to try the modifications. I suspect I'll learn a bit more about amplifiers, which would be a good thing as I know very little.

Good luck finding an amp to modify.

[Psycoacoustics]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

Thank you for the offer, but I want to try the modifications. I suspect I'll learn a bit more about amplifiers, which would be a good thing as I know very little.

Good luck finding an amp to modify.

Crap! Now I gotta search feebay! :D

Yea, that's why I tried to steal that amp from you. I'd like to learn too!

Good luck, let's us know how It turns out. Mark

[AJ]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

Crap! Now I gotta search feebay! :D

Yea, that's why I tried to steal that amp from you. I'd like to learn too!

Good luck, let's us know how It turns out. Mark

Look around for a Hafler and rebuild it. They are good amps to work on because they are simple, but offer better performance than the Dynaco 120, for instance.

[Pete Basel]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

tyger23 are there schematics for this amp online or do you have them by any chance?

[JRT]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

tyger23 are there schematics for this amp online or do you have them by any chance?

mentioned up thread:

Took me about 2 days, but I hand traced the entire schematic for the audio path. I requested a service manual from AudioSource, but they were kind enough to never send me a reply. :D

[tyger23]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

Just thought I'd post a quick update.

PE Forum user Arlis_1957 sent me his "Johnny Richard's" special (an original AMP-100). I've been listening to both closely for about an hour now, and there's significant improvement with my changes.

At first, it didn't strike me as obvious, but as I switched to more critical listening music (Norah Jones, Clapton Unplugged, Jeff Buckly, Dark Side of the Moon, etc) the changes became more and more evident. Maybe the caps/amps/etc needed time to warm up as well.

The two biggest changes I note are that the muddy-ness of heaving kick drums and bass lines is gone and a much more "airy" presence to the vocals. Now, the drums are crystal clear, allowing you to hear the slight reverberations as the drum falls off. Vocals no longer seem contained in a box. They are airy and clear. The reverb present in Buckly's "Hallelujah" comes out amazingly clear. The telecaster sounds like he's playing from a Matchless amp, rather than Line-6 solid state.

I'm definitely happy with these changes. Hopefully Arils_1957 will be as well.

Pete - I can probably send you the schematic that contains the overall topology, but I haven't taken the time to draw it out yet. Let me know if you're interested. Also note, I didn't take the time to re-construct the entire thing (auto-switching circuit, etc.), I only focused on the signal path.

[fastbike1]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

True, but . .. .

If your Dynaco 120 has cr*pped out, take a look at this : http://www.updatemydynaco.com/

Nice guy, great kit. End w/ new amp in original case. Great sound.

Look around for a Hafler and rebuild it. They are good amps to work on because they are simple, but offer better performance than the Dynaco 120, for instance.

[[email protected]]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

He hopes so too.

[[email protected]]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

by the way, did you notice how bad the balance was? i gave the pots a good cleaning and they got a lot less scratchy but still not so good.

[tyger23]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

It was horrid. One channel was nearly 1.5dB higher than the other. In laymen terms, one channel was doing 50% more power than the other. If one was 1W, the other was 1.5W. 3W vs 4.5W, etc.

I'll definitely get that fixed.

I had a few more people listen to the original vs. my changes today and all came away impressed with the differences. Bass is more punchy and overall the system is less 'muddy'. Hope to have it wrapped up and in the mail tomorrow.

[tyger23]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

So I finished up the rework for Arlis_1957 and noticed two things, that I've already corrected:

1. Had to add a step to the instructions to remove the RF trap capacitors near the amp.
2. Had to update the Mouser cart to change from two 27K resistors to four 27K resistors. This bumped up the price by 26 cents.

FYI - the newly modded amp sounded spot-on to my previously modded amp, so the results ARE repeatable.

Enjoy!

[mpotoka]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

So I finished up the rework for Arlis_1957 and noticed two things, that I've already corrected:

1. Had to add a step to the instructions to remove the RF trap capacitors near the amp.
2. Had to update the Mouser cart to change from two 27K resistors to four 27K resistors. This bumped up the price by 26 cents.

FYI - the newly modded amp sounded spot-on to my previously modded amp, so the results ARE repeatable.

Enjoy!

So just to confirm, the mouser link in post #4 has been updated?

Finished my car project so I think this may be next!

[tyger23]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

So just to confirm, the mouser link in post #4 has been updated?

Finished my car project so I think this may be next!

Yes - Mouser list in post 4 is looking correct now. Only thing I **might** suggest is using a Panasonic ECO-S1HP682CA instead of the Nichicon 6800uF bulk caps. I HAVE NOT tested this yet, but those Panasonic caps will fit without modification, whereas the Nichicon caps need to be tilted over in order to fit inside the case.

Again, I have not yet tested those Panasonic caps, but that series generally gets good reviews in the Audio community.

http://www.mouser.com/ProductDetail/Panasonic-Electronic-Components/ECO-S1HP682CA/?qs=sGAEpiMZZMtZ1n0r9vR22RSFeKT%2fCuZ6%2fKGpCVEhy%252b4%3d

[[email protected]]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

Got my amp back from Ty and the difference is obvious. There was a real muddiness, or congestion in the midrange/vocal area, now very clean and clear. I hadn't realized how bad the channel separation and balance was. now everything is more intelligible, instrument placement and such.
slim design fits so nicely under a monitor and with everything cranked its dead silent. Ty sent all the parts he replaced back to me. I'm glad I didn't attempt this mod myself.
Thank you Ty.

[tyger23]

Re: How to turn your AudioSource AMP 100 into a real amp. (Paying it forward)

Thanks for the compliment. Glad you gave me a chance to work through everything for you. I've been very happy with the changes, and I hope anyone else that tries this will be as well.