Sun Records Echo - How Did Sam Phillips Achieve It?

Found this on the web.Can anyone please explain to me in "simple" english what exactly the following paragraph means?Not being very technical oriented i find it a little hard to comprehend.

thank you

SUN TAPE ECHO

"By 1954 Sam Phillips had upgraded his equipment and installed two Ampex 350 recorders: one a console model and another mounted behind his head for the tape delay echo, or slapback". See http://www.history-of-rock.com/sam_phillips_sun_records.htm

The slapback/echo tape machine (#1, the mounted model) would typically record a dry signal from a local mike. The tape with the local signal, recorded less than a second ago, then reaches the playback head of the same machine. (Length of delay is governed by the tape speed of the echo machine.) The played back dry, local signal then goes into the console where it is mixed with signals picked up by all the microphones in real time, including the one also recorded on the reverb tape machine. The console tape machine finally records the mixed signal on its only track.

Assume a distance between the recording and playback head of 4 inches and echo tape speeds of
7.5 ips: Delay = 4/7.5 = 0.53 seconds (most likely the most common echo tape speed).
15 ips: Delay = 4/15 = 0.27 seconds (When It Rains It Really Pours).
(Update July 2004: 7.5 ips as the common speed of the echo tape machine has been confirmed by Roland Janes of Sam Phillips studio - thanks!)

So the distance between heads would correspond to the longer path if the wet signal is delayed with about half a second (7.5 ips).

Speed of sound at 25 centigrades (77 F): 347 m/s. It would take a distance of 180 metres to get the same delay (as 7.5 ips) that way. This means that it would be difficult to measure if a signal was recorded twice from both amplifier and microphones in a studio, but on the other hand the delay ought to be too small to be worth that extra procedure. One can but wonder if RCA thought of this in January 1956 when Heartbreak Hotel was recorded - perhaps they found out the hard way when they had to use the stairwell eventually.

 

More or less two tape machines recording and playing back the same thing at the same time. The second tape machine plays back the recording slightly later than the first, creating the tape echo.

 

OK, ever used a 3-head tape deck? If so you may have noticed that you can listen to (aka "monitor") the recorded signal played back off the tape while you are recording and that the signal being played back off the tape is slightly behind the signal being recorded to the tape.

Never mind if that means nothing to you!

When a tape is recorded to it is passed by the recording head at a constant speed. Now, there are two other heads in a pro-recording deck - one on either side of the record head. The one on the left of the record head is the erase head and that wipes any sound already recorded on the tape in readiness for the signal the record head is about to put on the tape. The one on the right of the record head is the playback head. Now usually you might think you wouldn't want to listen to the tape while recording it but this can be very useful since it allows you to adjust the recording levels etc and hear in real-time what the changes you are making are doing to the signal being recorded to the tape.

Anyway, the point is that since the playback head is a couple of inches to the right of the record head there is a small delay between the signal being recorded to tape and that same signal being played back though the tape head - that delay being the exact time it takes for any point on the tape to get from the record head to the playback head.

Imagine now that you were recording someone talking. You can hear them talking and that sound is being recorded onto tape. But if you also listen to the signal being picked up by the playback head it will be late - you would hear two versions of the same voice close together in time but not exactly in synch. Here comes the good bit - now imagine you record that delayed signal along with the live signal onto a second tape deck!

Voila - slapback echo.

You can actually do this with one tape deck:

The trick is to feed the delayed signal picked up by the playback head back into the record head!

Then you would not only have the voice you wanted to record but also a delayed version arriving at the record head too. However, if you are not careful you would get a delayed version of the delayed version of the delayed version forever repeating.......

To avoid this you need to ensure that the signal you feed back into the record head is at a lower level than the original signal. In that way you get a repeating echo of the original voice but one that is dying away by the same ammount each time.

You can play with the levels to create many dying echoes or, with a little experient it is easy to effectively get just one echo (the others being too quiet to really hear them clearly). This effectively gives you the "slapback" echo Sam Phillips achieved with two decks.

You can also change the tape speed or change the distance between the record and playback heads to get different delays.

I once managed to get a smooth reverb effect with this one-deck method - not quite sure how I did that but it sounded great!

Hope that helps

 

I believe it's worth mentioning that the significance of tape in all this is it gave a very discrete echo effect, more akin to yelling across a canyon than traditional artificial echo, which was a less discrete "big room" sound. In the early pre-tape head studio days, I believe that reverb was accomplished by routing the sound into a large reflective room and placing a mike on the opposite end of the room to add size to the sound. The tape echo added that slap to is so revered. I have a friend who still has a so-called echo chamber.

 

Indeed - the technical terms echo and reverb are often used interchangably but really are two different things. Echo is a distinct repeat of the sound after a gap of a given time interval whereas reverb is the continuous reverberation of the sound without a distinct gap being audible.

Echo is more commonly called delay these days just to confuse things further.

 

mmmmmmmm.........complicated but i think i'm starting to get it!Would a binson type unit give that type of effect?

 

Exactly the same principle at work .

 

...and just to confuse things even further yet, it's also sometimes called "feedback delay".

 

The tape delay is on PPM, but isn't everything after that just the chamber? I don't hear any delay on WTB, for example.

 

Bathrooms, hallways and staircases were sometimes put into use for echo chambers.
"Heartbreak Hotel" by Elvis used a staircase.
"Summer In The City" by the Lovin' Spoonful reportedly used an open
elevator shaft, for those big "waves" of echo after the drum beats on the opening.

 

would this type of echo be on the dull side of the eq spectrum or bright, like you hear on some digital unit settings where it reads "large room","hall1" etc.....?In other words:when slap back echo (or the EMI slap+echo) is applayed to a dry signal, which frequencies get boosted?

 

That all depends upon what you do with the signal you are delaying. You could EQ it before it gets recorded to the "slapback deck" or after it is read back delayed by that deck or you could do both!

If you applied no EQ at all then the slapback delayed signal would be ever so slightly duller sounding than the original signal.

If, for example, you want to hear the slapback clearly but quietly then you could EQ the delayed signal boosting the upper frquencies. Or you might cut some bottom end before it gets to the "slapback deck". In fact, there are a number of ways you could do it and all of them will sound slightly different. Analogue effects are so much more fun than digital ones and also produce much more interesting and enjoyable results .

 

My mother had this large washing machine. It had a glorious big sound. Of course, I didn't want to run it through sends etc. (I didn't know how anyway) so I used to do vocals by singing down into the washer, sitting the mike near the bottom on a towel.

In retrospect, it sounded very nice, but when I started recording others, I was too shy to suggest it.

 

Guitarist Scotty Moore also achieved the slap-back echo effect through the use of an EchoSonic amplifier. Designed by Ray Butts, it had its own tape delay unit built right into amp.

EchoSonic

 

I can't think of where I saw it, but anyone remember the site that had samples of the echo tape alone? I seem to remember a sync-up of that and the full mono track. A Johnny Cash song maybe?

 

Don't think it was Elvis...

 

It is on the site stereoptic mentioned. Go to "Info" and then the "ELVIS AT SUN - An Overview of the Audio Restoration" section and scroll down to the footnotes.

 

Ahh, you're right. Knew it was Johnny Cash though!

 

Steve Hoffman wrote " Now, take the Sun Records echo slap, slow the tape machine down to 7 1/2 ips (for a longer delay) and ONLY feed the echo from an echo chamber into it. Feed that back into the dry signal and you have the classic EMI Abbey Road echo used on the first Beatles' records (and everything else British Invasion from EMI from 1962-66."


Now......would compression/limiting be a part of the equation at this point?How much would that "color" the overall sound?Would that also be akin to what you hear on an early Everly bros record or is that a whole different story?Sorry if i'm getting anal but all these different techniques are fascinating.

 

Cool!

 

For the most obvious example of the EMI/Beatles effect that Steve describes, listen to the end of "Thank You Girl." They really cranked the tape-delay/echo chamber effect up on the vocals, and there's definitely a delay at work, just on the echo (i.e., not on the dry vocal). (It's really obvious on the unprocessed bootlegged outtakes of that edit piece.)