Vintage Heathkit W4-AM Williamson Tube Mono Blocks Serviced Super Sweet

Where do I begin with these lovely Heathkit mono blocks? They came up great on a variac, reforming the supply caps, and after replacing a couple of fairly tired 6SN7s these were ready to test. One amp sounded great and the other, not so much.

It turned out there was a resistor on the driver that had just about gone open. After building up an equivalent value to the original I tried again and behold, glorious sound! These amps were rated at 20 watts, and a quick sweep on the scope showed them both to be putting out exactly 21.5 watts at clipping. What really impressed me though was that I was able to achieve full power output down to at least 30hz which is mighty impressive for a smaller vintage amp. I probably shouldnt be surprised though as Im pretty certain that these used some fine Stancore transformers which are quite large for the output these amplifiers offer. Okay, the test bench is one thing, but what I really wanted to do was listen. I pulled my VanAlstine modified Dynaco ST70 from the system and set these up and was nothing less than blown away by what I heard! It wasnt the same as the Dynaco. Indeed, the ST70 with its extensive mods and greater output ability proved to be a little more detailed and capable of greater dynamic slam. Still, the Heathkits proved to be so musical, warm and inviting that I couldnt pull them from the system. LP after LP for hours on end. Then for weeks and eventually months.

Other than being a little underpowered for my relatively inefficient speakers, I simply had no desire to stop listening to these wonderful sounding amps. Quite simply, to say I was shocked at how good these sound would be an understatement! In addition to the wonderful sonic presentation, these also look pretty good too!

As the pictures will show, the chassis are clean with a minimum of corrosion or pitting (mostly on the bottom or sides). The gray one does show some scratches on the transformer cases.

Yes, one is copper colored and the other gray. The owner started as mono in 1956 and then bought the other in 1958 when going to stereo. Considering the vintage, these have held up reasonably well from a cosmetic standpoint. Operationally, these have been great too.

I did re-solder the ground tabs on one of the supply caps as the joint was slightly loose and would cause buzzes and crackles. Thats now gone and its sounding perfect. The other amp will rarely have a brief very low level kind of rustling sound that Ive only noticed when the amps are on with nothing playing (its that quiet). Ive gone over all the voltages and everything checks out. I could chase after resistors looking for thermal noise, but its so rare and brief and unobtrusive that I finally gave up on hunting and just enjoyed these for about six months before pulling them. Sound like I love these? So now its your chance to fall in love with these great amps too! The item "Vintage Heathkit W4-AM Williamson Tube Mono Blocks Serviced Super Sweet" is in sale since Sunday, August 11, 2019.

This item is in the category "Consumer Electronics\Vintage Electronics\Vintage Audio & Video\Vintage Amplifiers & Tube Amps". The seller is "saybrooksound" and is located in Old Saybrook, Connecticut. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, South africa, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Singapore, Switzerland, Norway, Saudi arabia, Ukraine, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Brazil, Chile, Colombia, Costa rica, Panama, Trinidad and tobago, Barbados, Bangladesh, Bermuda, Bolivia, Ecuador, Egypt, Guadeloupe, Iceland, Jordan, Sri lanka, Luxembourg, Macao, Martinique, Maldives, Peru, Pakistan, Reunion, Viet nam, Uruguay.

• Model: W4-AM
• Modified Item: No
• Country/Region of Manufacture: United States
• Type: Tube Amplifier
• Brand: Heathkit