Pioneer SX-1000TW power specs?

WickedSharp

Scratchy and crunchy is how I like it
Hello,

I've got my eye on an SX-1000TW with a sticker on the front that says "FET IC 150 Watts".

Most information I've found on the internet says that this receiver is "50 watts RMS". ** Note that it says "watts" and not "watts per channel".

I saw one bit of data that says this receiver is 25wpc RMS at 8 ohms, and 27wpc RMS at 4 ohms.

So, what do you think? My guess is that it's 25wpc at 8 ohms.
 
I know that "watts" are measured differently these days when compared to 1969, so let me change the question.

Would you match an SX-1000TW with a set of vintage Rectilinear XII speakers?
Would you match an SX-1000TW with a set of 1973-vintage Smaller Advent Loudspeakers (4ohms!)?

Now for the kicker...
Would you match an SX-1000TW with a set of a/d/s/ L9e (4ohms)?

Thanks,

Steve
 
That's what I was hoping. Thank you!

It's weird that the SX-1000TW is 50wpc in 1969, and the SX-780 is 45wpc 10 years later.

If it works out on Saturday, I'll post pictures.

Steve
 
It's one of my favorite receivers for sound, build quality, and looks. Mine's currently resting while an SX--750 fills it's slot, It's no slouch either!
 
The SX-1000TW's are great receivers - they are pretty darn powerful for their time plus they have very good tuner sections too. The power amp is a cap coupled push-pull "quasi-complementary" design using four identical NPN transistors for the outputs (PNP transistors were expensive and difficult to make back then) which tends to make a very warm sounding amp. The power ratings can vary depending on whether both channels are driven or only one at a time, how high the distortion levels are @ the rated power and the speaker load impedance etc. Basically they are considered 45-50 wpc @8 ohms. Disregard the IHF wattage ratings, they are BS and pretty much useless inflated advertising numbers used before the FTC stepped in and cleaned things up.

They are an older simpler design but IMO they sound great and look beautiful plus they are in a nice small package (usually with a very attractive Walnut case too). Also available as the Allied 395 receiver.
 
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The SX-750 is a more modern complimentary (NPN/PNP outputs and balanced positive/negative power supply rails) direct coupled amplifier and is capable of more and "cleaner" power with less distortion but the power ratings are roughly the same as the SX-1000TW. Since it's direct coupled and produces a decent amount of wattage it includes a speaker / output protection relay. The 750 is also a very good receiver with a very nice tuner section and discrete outputs, a bit more "accurate" sounding than the cap coupled 1000TW. Both pack plenty of power for their size, depends on the sound you're looking for I guess. I like 'em both of course!
 
So the SX-750 and the SX-1000TW are similar power-wise?

My apologies, I just realized that you were originally asking about the SX-780 but then later asked about the SX-750. My comments above are directed towards the SX-750, personally I don't care for the SX-x80 series of Pioneer receivers.
 
Well, I own it now. I was able to get away at lunchtime to take a look.

1000TW.jpg

Purchased for $50 from the original owner. He bought it new while serving in Vietnam. He reports 100% functionality and that it has never been serviced. I did not plug it in before buying it. I did turn some of the knobs and noted that while they are not gritty, they do seem pretty stiff.

Tips on how to proceed? Should I just light it up and go?
 
I'd plug it into a dim bulb tester and switch it on first. Sometimes bias pots can corrode and go open if it's been sitting for years so you might just save yourself some trouble by doing that. If the bulb dims down then I'd get some contact cleaner ready for the controls if it needs it.

Be very careful when cleaning controls or other things not to let anything, not even water get on the backside of the dial glass. The numbers and letters will lift right off and rearrange themselves into crazy looking hieroglyphics (happened to mine unfortunately).

Follow any control cleaning with a blast of clean air and some control lube like "faderlube" or similar and you should be good. Nice looking piece, congrats!!
 
Funny,

I cleaned the back of the dial glass on mine with water and a q-tip without problems. I must have been lucky not to do any damage!
 
I'd plug it into a dim bulb tester and switch it on first. Sometimes bias pots can corrode and go open if it's been sitting for years so you might just save yourself some trouble by doing that. If the bulb dims down then I'd get some contact cleaner ready for the controls if it needs it.

Be very careful when cleaning controls or other things not to let anything, not even water get on the backside of the dial glass. The numbers and letters will lift right off and rearrange themselves into crazy looking hieroglyphics (happened to mine unfortunately).

Follow any control cleaning with a blast of clean air and some control lube like "faderlube" or similar and you should be good. Nice looking piece, congrats!!

Which size bulb to use?
 
Deoxed, dusted and cleaned up some. New bulbs hopefully tomorrow and then I can button it up and give it a test.

This might become my first recap effort since (fingers crossed) there are no issues to troubleshoot. Dim bulb test was good.

IMG_2632.JPG IMG_2633.JPG IMG_2634.JPG
 
I have an SX-1000TW.
Take audiojones's precautions regard the fragility of the dial paint to heart.
I lost quite a bit of paint from mine under the force of a wet Q-tip, held from dry end and wiped across the surface.
 
I have an SX-1000TW.
Take audiojones's precautions regard the fragility of the dial paint to heart.
I lost quite a bit of paint from mine under the force of a wet Q-tip, held from dry end and wiped across the surface.

I didn't even touch the inside of the glass thanks to the warning!
 
Playing and sounding good!

IMG_2636.JPG

The Rectilinear's sound really really sweet with this one.
 
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