Ramsey SHA1C Stereo Headphone Amplifier Kit

by Ramsey

Product Details

• Item Weight: 3.8 ounces
• Shipping Weight: 1.5 pounds (View shipping rates and policies)
• ASIN: B0002NRL7U
• Average Customer Review: 4.0 out of 5 stars  See all reviews (7 customer reviews)
• Date first available at Amazon.com: July 21, 2004

Product Description

So, you buy a really good radio or CD player, go to plug in your headphones, and there isn't a headphone jack! You find a line level jack, plug in your headphones, and they sound terrible. Sound familiar? Most good quality gear lacks an earphone output, or if there is one, it is woefully poor quality. We developed this kit to help us listen to our mixers, reverbs, voice recorders and other audio goodies. We took a pair of LM-386 250 mW audio amplifiers, added volume controls, power supply and a handy, switchable, high-cut filter. A common 1/4 stereo earphone jack is used for the output - assuring compatibility with all stereo headphones - and RCA phono jacks accept standard line level input signals. There's plenty of volume and of course, the Fi is quite Hi . Available in money saving kit form or fully wired and tested (model SHA1WT). Runs on 9 to 15 VDC. If you need an AC power supply, check out our AC125. Includes an attractive matching case measuring 5 W x 1 1/2 H x 5 1/4 D. (Did you know the leading manufacturer of high-end table radios recommends the SHA1C to all their customers?!)

Customer Reviews

Most Helpful Customer Reviews

11 of 12 people found the following review helpful:

4.0 out of 5 stars Nice, but needs a few improvements, July 16, 2006

By 

Gourmet Geek - See all my reviews

This review is from: Ramsey SHA1C Stereo Headphone Amplifier Kit

This is a very wide bandwidth amp and should be capable of driving just about anything you have.

What I cannot understand is the way they implemented the volume controls. Not only are they separate, which means you have to readjust the balance every time you adjust the volume, but they used linear (rather than audio taper) pots with the left on the right and the right on the left. I can see doing that if you are putting a quick prototype together out of spare parts, but if you can order parts or get to a good electronics store there is no need and if you are selling it as a commercial product there is no excuse.

I replaced their volume controls with a conductive plastic dual gang 10k audio taper for volume and a dual 5k linear taper in series on the signal side for fine balance adjust. They don't fit in the circuit board so the wiring inside isn't pretty, but it's much more convenient to use. I also bridged the switch for the sibilance filter with resistors to eliminate the ear splitting click the first time it is engaged. Anything around 3 mega ohm or above should work. That filter comes in very handy with my Beyerdynamics DT-770's which have enough high end definition to cause physical pain when listening to low quality streaming audio where the high end is all compression defects.

9 of 10 people found the following review helpful:

5.0 out of 5 stars Great sound, January 19, 2005

By 

W. Chen "attic lodger" (Malden, MA) - See all my reviews
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This review is from: Ramsey SHA1C Stereo Headphone Amplifier Kit

I use this amplifier with Grundig S350 radio(line output) and Sennheiser HD280 headphone. They form a great music system; it seems to me that all of the three devices have quite a flat response.
Before you use it, you hvae to spend about an hour putting the components in the PCB and solding them. It took 20-30 hours to burn in. One thing I feel uncomfortable about is it is in lack of a battery compartment; if you want to install a 9v battery you have to unsrew two long screws and open the cover.

5 of 5 people found the following review helpful:

5.0 out of 5 stars Good amp for a good price., March 7, 2006

By 

J. Enright (Jacksboro, TX USA) - See all my reviews
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This review is from: Ramsey SHA1C Stereo Headphone Amplifier Kit

This kit provides quality components and clear detailed instructions. Anyone who can solder should be able to assemble it in under an hour. The result is a quality amplifier for a great price.

Like another reviewer, I am dismayed by the fact I have to remove two over-long screws, thus opening the amplifier case, to change the battery. As a result, I will rarely, if ever, run the amp on battery power. It is currently working great on a cheapo variable voltage "universal" wall-wart. I expect it will always run this way.

This amp connects a Bose Wave Radio / CD to Sony MDR-V6 pro headphones. My only complaint is that the amp volume must be run at or near minimum to prevent brain damage. The sound is clear, crisp, and big. No complaints at all on the function of this amp.

Buy this amp. The assembly is piece-of-cake easy with no surprises or tricky operations. Great instructions including the design theory for hobbyists. The amp produces great sound and has good usability as far as control function and placement. And the price can't be beat.