echoplex pitch drifting and repeat distortion

[markphaser]

What can cause pitch drifting or repeat distortion from a maestro echoplex?

[Seljer]

Pitch drifting would probably be something to do with the speed of the tape not being constant when its writing to the tape/reading it back
and distortion is just from the sound being transferred on and off of the tape multiple times, loosing quality each time its written onto the tape and played back

[Meanderthal]

 Well, there's also the possibility that the tape loop is wearing out... if you really have to you can splice up a loop of 1/4 in. tape. I know a guy who does this to his about every other week!

[nightingale]

Hi,
My EP-3 did the wierd chorus-ey pich shifting for a few months before the motor died.
I have seen some motors on the net for $75 or so?
hth,

[captntasty]

I'm no expert when it comes to EP's, but had to keep tape machines running way back when.  If the tape cartridge is old you might need new tape loaded.  Have the heads been cleaned and degaussed?  The belt from the motor will wear out also - it gets loose and can slip and cause the tape to record and play back a little faster then slower which might account for the pitch change.

[markphaser]

1.) The belt from the motor will wear out also - it gets loose and can slip and cause the tape to record and play back a little faster then slower which might account for the pitch change.

2.) speed of the tape not being constant when its writing to the tape/reading it back

I'm trying to find the echoplex parts list chart

Pinch rollers

The echoplex does do a chorusing effect wow and warble kind of sound its has to do with something mechanical

What can cause the tape heads or record heads to cause distortion or fuzz?

Their is biasing trimmers that set the repeat distortion and input distortion

The feedback doesn't self oscillate like it should also i wonder why?

[markphaser]

1.) What kind of "cleaner" can i use to Clean the record and playback heads with?
2.) What kind of "cleaner" can i use to Clean the tape path?
3.) What can i use to clean and recondition pinch roller?

4.) Echo sustain  doesn't regenerate but it does repeat but doesn't regenerate what can cause this please?

5.) How can i clean or adjust the capstans and guides?
6.) how can i Adjust the leaf spring tension?

6.) What would cause a echoplex to make a warble sound?
             a.) The capstans?
             b.) The guides?
             c.) Motor speed?
             d.) motor belt
             e.) Pinch roller
             f.) leaf spring tension

What can i use to lube or clean the motor with?

What can i use to clean the tape ? would rubbing alcohol work?

[R.G.]

1.) What kind of "cleaner" can i use to Clean the record and playback heads with?

70% isopropyl alcohol and a Q-tip

2.) What kind of "cleaner" can i use to Clean the tape path?

70% isopropyl alcohol and a Q-tip

3.) What can i use to clean and recondition pinch roller?

70% isopropyl alcohol and a Q-tip

4.) Echo sustain  doesn't regenerate but it does repeat but doesn't regenerate what can cause this please?

Almost any defect in the regeneration loop. There are many possibles, beyond the scope of this forum.

5.) How can i clean or adjust the capstans and guides?

70% isopropyl alcohol and a Q-tip, and a screwdriver.

6.) how can i Adjust the leaf spring tension?

screwdriver

6.) What would cause a echoplex to make a warble sound?
             a.) The capstans?
             b.) The guides?
             c.) Motor speed?
             d.) motor belt
             e.) Pinch roller
             f.) leaf spring tension

Any one or more of the above in any combination.

What can i use to lube or clean the motor with?

70% isopropyl alcohol and a Q-tip, then 3-1in-1 oil.

What can i use to clean the tape ? would rubbing alcohol work?

You really can't. The tape is lubricated for this use and cleaning it removes the lubrication as well as the oxides that do the recording. Replace it, don't clean it.

Before you ask, 70% isopropyl alcohol is commonly known as rubbing alcohol.

[markphaser]

Thanks alot R.G for the information for me and everyone else who reads this

Almost any defect in the regeneration loop

Can it be in the preamp section? because it is regenerating alittle because it does repeat

The echo sustain know 1 to 10 if u crank it to 10 it doesn't self osc. regenerate u know what i mean

If the preamp section is not biased right can this effect the regeneration section?

[markphaser]

Why does the record head doesn't fully erase the previous signal on each new iteration?

Why does it distorts the new iteration?

With more repeats does it overloading the 1/4 inch tape in the echoplex? and why please?

[Meanderthal]

 Those last 3 questions indicate dirty or worn tape heads. Try cleaning them(and everything else) with rubbing alcohol as R.G. suggested. However, be aware that if they are dirty or worn, so is the tape itself... Sooo... you will need new tape too.

[Mark Hammer]

I don't own an echoplex so I haven't seen what all the relevant components are made out of.  However, I might urge a little bit of caution on some of RG's recomendations.  While there is no argument from me about isopropyl alchohol as a cleaning agent for the gunk that builds up on tape systems, it can also tend to dry out those parts that need to remain supple and rubbery over time, such as pinch rollers.  Those things need to grip the tape firmly to move it along, and if they are merely clean and rigid they can end up spinning around and providing unreliable and erratic tape movement.  There ARE products on the market that have names like Rubber-Renew, which are specific designed to maintain the original texture of the material, as well as parts made of similar materials like drive belts.  One can usually find this in any place that services VCRs, tape decks or turntables, or sells supplies for people who service them.

As for getting optimum sound out of a tape-based system, note that what can seem like very tiny distances/spaces to us humans can have very big effects on sound quality when it impacts on a tapehead reading faint magnetic impressions left on thin magnetic tape.  Any dirt build-up on the head creates a huge gap between the tape and tapehead, reducing signal sensing.  tape heads also need to be adjusted so that they are perfectly perpendicular to the tape path.  Not only in terms of whether the tape head might lean a little forward or backward from its base, but also how much it leans to the left or right.  Take a piece of paper with some 10pt text on it and tilt the bottom of the page away from you about 20 degrees or 20 degrees to one side (left or right) and you'll see that it becomes much harder to read accurately.  Same thing with tape.

Tape heads and some other parts along the tape transport path can also become magnetized over time, the same way your car or house keys can, and these can impact on sound quality.  Demagnetize often.

Finally, tape types vary in their coercivity (how strong a magnetic trace can be stored on them).  Although newer high-coercivity tape types provide a tremendous improvement in S/N ratio, you have to consider them as being a bit like plugging a guitar into a mic input on a PA: if you have switches to adjust the sensitivity of the tape electronics (e.g., a CrO2 vs FeO2 switch) the same way you would for a mixer input, then everything works out fine.  If the tape is too "hot" for the recording electronics, then you can produce some distortion, or at least unpleasant tonal balance.

[Peter Snowberg]

When I did in-shop computer repairs, we always used petroleum naphtha (a.k.a. white gas) for cleaning printer platens and assorted rubber parts. Most of the time it removes all the gunk and leaves the rubber in great shape. Rubber parts that I thought were completely toast were often rejuvenated after a naphtha cleaning. Use with caution It may eat some types of rubber and it will eat some types of plastic, but I've not had any bad experiences with rubber.

Very often we would get printers in the shop that would not feed paper through them. 5 minutes with naphtha and a foam-type Q-tip and they were fixed.

The other "magic" cleaner we used was lemon extract from a bakery supply company. It's surprising how good of a general cleaner it is for cases and how fast you can go through a gallon of it. As an added bonus, it leaves your equipment lemony fresh.

[Doug_H]

I used to use some kind of rubber reconditioner on the pinch roller of my tascam 4-track. I agree, don't use alcohol on rubber parts as it will dry them out.

[slacker]

We used to have a large envelope stuffing and sealing machine at work for doing large mailing distributions. That had a lot of rubber rollers in it and the manufacturer supplied us with some "rubber roller cleaner" that was infact just acetone. We've since used it on the rollers on printers and other things without any problems.

[puretube]

~39 years ago, we used do drip a little drop of adhesive gum
on the capstan of one of the Magnetophones of a wellknown
local HAM & Stockhausen-admirer.

The sounds that came out of the sound reproducing devices
were way ahead of their time (see: time-based effects).

The vocals uttered upon this event by the tape-artist
were way above the  comprehension of his carbon-microphones,
and the capability of his all-tube compressors.

The echoes throughout the building were perplexing...

[markphaser]

The preamps section is different in each echoplex models why is that?

What is it called after the preamp section? what stage would it be called before the tape record head?

When looking at the EP-1,EP-2,EP-3 ,Seriko and other echoplex models some use a FET or a transistor
and the biasing resistor values are different and so it the biasing design of the FET or transistor from each model
and revision i wonder why they did this

Echoplex block diagram:
1.) Preamp/buffer
2.) record head preamp section(this has biasing trimmers for the tape biasing and tape head biasing)?
3.) recorded onto the actual tape
4.) playback head preamp section? this has biasing trimmers also
5.) output preamp section to output jack
6.) The regeneration stage sections are different in each revision and model from echoplex