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Hi Scott:

I rebuilt one of those WA-P2 preamps and put nice Telefunken tubes in it (barely used, salvaged out 
of a junker Ampex consumer reel deck), and it is a good listening-playback system for 78's and mono 
LPs. One of these days I'm going to build a proper mono system with a corner horn speaker Williamson 
power amp. As it is, the Heath preamp does very well feeding an Ampex amplified speaker, and 78 
playback is quite nice because the speaker doesn't go low enough to reproduce rumble or high enough 
to produce all the surface hash in the top octave of human hearing. Those familiar with the Ampex 
speaker-amps know that they were designed for broadcasters and sound particularly good in the main 
voice frequencies, which again makes them very euphonic (if not critical-accurate) for 78's. The 
impedence match between the output of the preamp and the input grid of the power amp is also fine, 
whereas some modern gear wants a lower source impedence.

With my WA-P2 rebuild, I rigged up a PSU out of two PowerOne blocks, one for B+ and one for 12VDC 
heaters (you have to rewire the circuit for direct power of the heaters without doubling the 6.3 
spec'd volts. The noise floor is probably a good bit lower than stock, since it was designed to take 
power from the Williamson power amp. The high-voltage PowerOne bricks are getting harder to find on 
eBay.

Those Heath power amps went through an evolution. The ones with the Peerless output transformers are 
said to sound the best, I think those were the early or middle versions.

-- Tom Fine

----- Original Message ----- 
From: "Scott D. Smith" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, April 18, 2012 8:12 PM
Subject: Re: [ARSCLIST] ye olde hi-fi history and eye candy


> Tom:
>
> Great post. Thanks for sharing. I remember those old Heathkit amps well! First hi-fi my parents 
> had, along with the matching WA-P2 preamp.
>
> --Scott
>
> Scott D. Smith CAS
> Chicago Audio Works, Inc.
>
> On 4/16/2012 8:01 PM, Tom Fine wrote:
>> Apparently there is a limit to YouSendIt. Here's another link, but it probably won't work for too 
>> long. Someone feel free to host the file online.
>>
>> https://rcpt.yousendit.com/1466402249/9d2166e198b7c46200a720cbf5655c72?cid=tx-02002207350200000000&s=19104
>> (make sure to paste complete link in your browser)
>>
>> -- Tom Fine
>>
>> ----- Original Message ----- From: "Michael Gillman" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Monday, April 16, 2012 7:25 PM
>> Subject: Re: [ARSCLIST] ye olde hi-fi history and eye candy
>>
>>
>>> On Mon, Apr 16, 2012 at 5:52 AM, Tom Fine <[log in to unmask]>wrote:
>>>
>>>> http://www.yousendit.com/**download/**M3BsSmJ3YTI1bmdLSk1UQw?cid=tx-**
>>>> 02002207340200000000&s=19102<http://www.yousendit.com/download/M3BsSmJ3YTI1bmdLSk1UQw?cid=tx-02002207340200000000&s=19102>
>>>>
>>>> From High Fidelity Magazine, April 1966. "How It All Began," chronicles 15
>>>> years of gear and hi-fi news/trends. The guy whose 1951 playback system is
>>>> pictured was obviously not married at the time! That setup has a WAF of
>>>> ZERO.
>>>>
>>>> -- Tom Fine
>>>>
>>>
>>>
>>> "Sorry this file has expired and can not be downloaded. "
>>>
>>
>