Bill333's System

Hi Sonic,

None of the tape decks that I own or am about to own have direct from the head output.  My assumption was always that I would be going into the machine and modding it to attach the head output to the external preamp.  I don't know about other head preamps, but the Bottlehead kits come with explicit instructions for doing this with the Otari and the Technics.  I'm kind of looking forward to it, actually.  If things go well, I may even try building my own head preamp from other designs.  As far as I can tell, these are really just phono preamps with a different equalization.  I've seen a forum post that talks about modding a Hagerman Bugle for use as a head preamp.  They just needed to change a few resistor values.

Regarding tape stock, I think there's one other company currently making tapes - RMG/Emtec.  Their products can be easily found on Amazon.  If I have to use one or the other, I would probably go with ATR since I think that's what the Tape Project is using.

Making azimuth and other adjustments to the head actually sounds appealing to me.  I always enjoyed the equipment/technical part of this hobby, so getting the necessary equipment and learning to do the calibration would be pretty cool.

very handsome

Congratulations Bill333

That's a beautiful machine!

Looks like you are all set up technically, mentally with all the skills to take on this adventure.

I read on one of the threads that the sound of the Otari tends to more punchy transients while the Technics is smoother and more musical.

Sonic

Ok, I finally got a few tapes and a take up reel and have started listening and tuning.  I had carried the deck to the upstairs loft and set it on the floor before I took my first listen.  (I'm leaving out the part where I had to watch youtube videos to figure out how to play a tape.)  I cued up 'We've Only Just Begun' by Ray Conniff using the internal headphone amplifier and was immediately underwhelmed.  The dynamics were very poor and it lacked detail.  I changed out the headphones for the Beyerdynamic DT990s, but the impedance of these phones is such that max volume was insufficient to reach normal listening levels, so I switched back to the cheap pair I had been using.

So I'm at a starting point, where do I go from here?  I thought the first step was to get it off the carpet    and on to someplace where it'll be easier to work on, so I carried it downstairs to the kitchen counter where I originally photographed it.  Doing this made a considerable improvement in sound with better dynamics and more detail.  Still far short of what I'm used to hearing from my digital systems, but an improvement.  

Having met some success changing out the platform underneath it, I laid it on its back so that the reels were horizontal.  Oops, there went the sound, muddy and bass deficient.  This thing doesn't like being on its back.  I put it back upright and took off the wooden side panels.  Unlike the 'wood' panels on some vintage gear, these appear to be the real thing, and about an inch thick.  This removed a hefty portion of the bass.  I figured that subsequent screw loosenings in the chassis would bring the bass back, but that never happened.

I removed the fiberboard back panel and the metal top panel without much effect.  What did make a big difference was the removal of two badly overtightened screws attaching the feet on the back.  More dynamics and more detail.  Here's a picture of the work in progress:



So now I'm going through the chassis loosening the screws.  Mostly just things that are easily reachable, the sonic effects range from 'nothing much' to 'ok, now I'm hearing some music'.  This tape deck is held together with dozens, if not hundreds, of screws and many of them are so tight that I can't unscrew them without drilling them out and using a backing bit on them.  And those are the ones I can even reach.  To really loosen the structural tension in this deck would require an almost complete disassembly.  That being said, there were some points where things were sounding pretty good.  Or at least better.  The problem is that it seems to want to settle back to its starting point.

During dinner last night I gave the headphones to my wife so she could hear the results of my tuning.     She wrinkled up her nose and said, "The music is fine, but there's something wrong with the vocals.  They sound garbled."  You've got to love my wife; she's the farthest thing possible from an audiophile, but if you put her in front of a system with anything less than top fidelity she'll let you know about it.     To my ears it sounded more or less the way it had all day.  I'm not sure if it's the deck, the forty year old four-track tape, the headphones, or what but she had a point.  The vocals didn't sound particularly off to me, but the sound is not what I would call high fidelity.

I have to admit to feeling a bit discouraged right now.  Taking off the panels and loosening the screws hasn't been a panacea, but maybe I just need to go farther.  I'll try cutting the wire ties off and see where that takes me.  If anyone has any advice, I'd like to hear it.

UPDATE: A day's worth of settling did the Technics a lot of good, and cutting off the wire ties did even more.  The sound is actually pretty listenable now.  I need to hook it up to the speaker-based system to really hear what it's doing, but I feel like I'm out of the woods.

Hi Bill333

A fascinating post from you. What you say reflects something Michael posted about studio reel decks where he found the angle of the machine was mounted affected the sound. And here you are experiencing it -- mounted upright gives more bass and clarity than horizontal though both are catered to by the manufacturer.

How's more tuning of the Technics going?

Sonic

Hi Bill

What speed are you using?

Also, if you make new side panels, make them so they go all the way down so you are not using the decks feet, but the side panels as your feet. If you float the transfer out to the sides properly then down, the flow will be more consistent.

have fun, the force is with you

Hi Sonic,

I haven't done much tuning since the post.  I've been listening to my tapes, trying to get a handle on what I'm hearing.  After listening carefully, I think the garbled vocals on the Ray Conniff tape are part of the recording or the tape, not the playback.  Some portions of the song I played for my wife do sound weird, other portions are fine.  I think she just caught one of the weird sections.    I'm not sure if that's on the recording itself, or if the tape is distorted but there are some odd sounding things with some of these.

I'm not sure what the next steps with tuning the deck are.  I'd like to go through and loosen all the screws, but many of them are so tight I'm afraid of stripping them.  Maybe if I took it to a repair tech, he could get it apart?  I'd love to take it to an experienced technician and just say 'Pull everything out of here that isn't needed for tape transport' and strip the thing down to a metal front plate, the motors and an outboard preamp circuit.  I'm not sure how realistic that is.

In terms of the next steps with tape, I want to get some NAB hub adapters and one of the high quality 15ips tape releases so I can hear what this sounds like when I'm not dealing with 40 year old consumer grade software.  After that I think I'm going to go the Tape Project route with upgrading the tape handling hardware and building an outboard preamp.

Hi Michael,

I have 3 tapes - two are 3 3/4ips 4-track, and one is 7 1/2ips 4-track.  The 7 1/2 ips one is Gershwin's Rhapsody In Blue.  I was expecting it to sound way better than the 3 3/4 tapes, but it has its own distortion problems.  I think what I'm hearing there is a kind of 'wow' caused by a bent reel.  The plastic reel it's wound on is bent so that the edges of the reel are too close together in one area.  I can hear it squeaking as it pulls the tape through the tight part on every revolution.  This, I think can be easily solved with a new reel but I just have to get one.

The side panels sound like a great idea, I'll have to look and see what I have in the way of suitable wood.

Hi Bill333

Got to ask you if you have done a basick service of the Technics before playing the tapes. This will of priority include de-magnetising the heads, checking the tension of belts, greasing/lubricating what needs grease and oil?

Sonic

Hi Sonic,

The person I bought it from said he serviced it, and I have no reason to doubt him. He' s a tape deck enthusiast, not a professional technician, but I'm sure he did all of the same things I would have done and more. All switches, buttons, et cetera are working very nicely. If I want more, I'll need to take it to a repair shop. Fortunately, there are a couple within driving distance in the Chicago area.

From tapeheads.net:

Hi Soul Music,

I have done many tests with a magnetometer and the results were not very impressive and not on the side of one of these devices. We used the Handimag kit to find out what the story was. We found no residual magnetic readings to worry about around head on a unit that was several years old and had never been demagnetized. In addition to the lack of any change to the head area or guides and lifters, it was found that there was several times the reading coming through a aluminum and stainless steel plate that was in front of the reel motor- AC type in this case, that presented a much more likely danger area than anything that was produced or remained on the heads. The tape sits immediately in front of this AC field. Yet no one has ever complained that reel tapes they have ever self erased themselves while tape were spinning over this magnetic field.

The conclusion was brought that there is no need to de-gausse any of this more modern equipment and that greater magnetic fields exist around the tape that was not at all found to effect the tape negatively in any way. I also did 50 passes of the same tape over this same machine with a tone that was recorded at 10KHz to see if the lack of de-gaussing was really going to show up that way. The tape made it through all the torture without a significant level decrease regardless of the lack of degaussing the tape path. I guess those people selling these thing would not like my opinion.

On the subject of the screw driver [Remark from Sonic: he is replying to someone who tried to use a tape head demagetiser to de-magnetise a magnetic screwdriver with no success], I have tried that very same test and if the screw driver is brought near to the stem of the degausser then you should get a vibration or buzz. If you do not then there might be a case where the coil is open in the unit and no current flow means no flux of the magnetic field. The fact is that if the degausser is working correctly and you follow the instructions then YES, the screw driver will not pick up a screw after the treatment. I have seen it happen, demonstrated it and of course could explain it having studied Magnetic Fields and Waves in Engineering college. In fact my instructor was the President of Jefferson Electric in Chicago here.
__________________
Best regards,

Sam Palermo, BSEE and ProSquad Member
Skywave Tape Deck Repair- Chicago area
(630)616-0932 Office/ Email:skywavebe@sbcglobal.net

Past Teac/Tascam Lead Service Technician at Chicago Factory Service still doing repairs.
http://s609729863.onlinehome.us/tape...uipment-repair

Now accepting MC, Visa, Discover Cards!

Hi Sonic,

I haven't been doing much tuning, but I have done some listening.  It's a little early to tell, but I do think there's something about the character of the tape sound that I find appealing.  That being said, the sound quality is still well below what I'm used to getting from digital.  The failing in the sound quality is different from anything I'm familiar with, I've been calling it 'weird' or 'wacky' for lack of a better word.  I put the deck in as source for the speaker based system, but I'm still hearing the same distortion I was hearing with the headphones, just writ large.  

In thinking about what's responsible for this, it could be the tapes, it could be the tape path mechanicals are not where they should be, and it could be the machine's electronics are not in great shape.  Since I'm hearing this across all my tapes, both 7 1/2 and 3 3/4 ips, I think it isn't the tapes.  As far as tape path mechanicals go, there are clearly some things going wrong.  One of the top level tape guides is bent at an upward angle.  I think tape still rolls across it, but there is probably some stress created there too.  The plastic reels on all of my tapes are bent.  Looking at them from above while the tape is playing, I can see the reel wobbling back and forth as it plays.  And those are the good ones - the bad ones are pinched together at one point so that the tape squeaks every time it completes a revolution.    This however, is a pretty easy thing to fix: I just need to wind the tape on to a pair of good metal reels before I play it.  This is probably something I'd want to do before playing a tape for best sound quality, anyway.

Which brings us to the electronics.  I called Sam Pallermo at Skywave Tape Deck Repair to talk about my deck.  He said that these decks are all about 40 years old and need to have their caps replaced to bring them into good working order.  Sam is a frequent poster on the Tapeheads.net forum, and by reputation one of the best tape repair techs still working.  The good news is that he's frugal with his customers' money and charges very reasonable prices.  Even better news is that he's located only about 30 miles away, which means I don't have to ship the deck.  Now that's a real gift.   So the next stop is to get the deck over to Skywave and have it completely recapped, repaired, and recalibrated. The downside is that Sam has a considerable backlog of work, so it will probably be two or three months before I get it back.

I'm not worried about screw loosening affecting the stability of the deck's playback. All of the playback mechanicals are attached to a thick molded metal faceplate, so what I do with the rest of the chassis shouldn't cause any problems. I don't think there's any possibility of the playback path becoming wobbly if the screws are loosened a bit.

Regarding the demagnetizing, your post is along the lines of what I've been reading also. I'm glad enough to leave an unnecessary maintenance task behind; demagnetizing never made sense to me anyway. How do you perform a delicate task using powerful magnetic fields with no way to tell how what you're doing is actually affecting anything? I'll just concentrate on keeping the heads and the tape path clean.

Hello Bill333

You said "It's a little early to tell, but I do think there's something about the character of the tape sound that I find appealing. "

Could you briefly describe what this appealing characteristic is like?

Sonic

Hi Sonic,

My impression is that it has a relaxing quality that I don't often get from digital.  Or it could just be my imagination.  I'll be more confident after I've had a much longer period of time to evaluate.

One thing that is new is that I got a copy of Abbey Road on 7 1/2 ips 4 track.  After losing a string of auctions for different tapes, I hit the jackpot and won my favorite album of all time and my go-to reference recording.  So what does Abbey Road on tape sound like compared to the digital I've heard hundreds of times?  My overall impression is that the sound is well below the quality of even an untuned Magnavox.  The sound was stuck in the speakers and very blurry and ill-defined.  The tonal balance was very bass heavy compared to the CD, although it still managed to be harsh on some of the high frequencies.  Again, I don't know how much of this is due to the tape's master, the condition of the tape itself, or issues with the playback machine.  I'll know more when I get the deck back from the repair tech. And I'll know a lot more if I can ever get my hands on one of those 15ips copies of the Abbey Road master tape that are supposed to be floating around...

I wish I had one of my old Studers around so I could go head to head with the Maggie. There's something about those Maggies

"My impression is that it has a relaxing quality that I don't often get from digital. Or it could just be my imagination."

Yes, tape done right (IMO) is very relaxing.

I've been listening to more tapes and I've come to the conclusion that the problems I described above with Abbey Road were due to the tape deck being cold from having been just turned on.  I've since taken to leaving the deck powered on and the sound is much improved.  With good quality 7 1/2ips tapes I think I can honestly call the sound high fidelity.  Not as good as I'm used to from digital, but still listenable.  Reviewing the tapes I own makes it clear that the quality of the 7 1/2ips tapes varies, but the 3 3/4ips tapes are really not good at all.  The sound is distorted and the speed seems wrong.  Plus generally fuzzy and undetailed.  But the best of my 7 1/2 ips tapes give clear sound and a good soundstage.  

In the next week or so, I'm going to take the deck to the technician and I probably won't see it for a few months.  So it'll be back to digital for a while.

Hi Bill333

A fascinating to read. Your observations of speeds and Sonic's corroborate -- if you want to go tape forget about 3.75 ips. A minimum for good musick is 7.5 ips. Where does that leave 1.75 ips cassette? Was the late and great Nakamichi-san chasing the wind with his 3-head decks?

Then Sonic read on one of the reel tape sites that 15 ips is best in terms of sound and oddly 30 ips is not as balanced in sound as 15 ips.

Sonic

Hi Sonic,

I can't speak to the 30 ips tapes, but I do have a couple of 15 ips tapes.  I haven't been able to play them yet because I need a set of NAB hub adapters, but I'll post my assessment of the sound when I've heard them.  The adapters should arrive any day now, so it should be soon.

In the meantime, I've been working on one of my 300B amplifier kits.  This time around I've made a real effort to custom fit the tube sockets to the pins.  Mostly I have used pliers and large diameter needles to open up the metal sheaths so that they fit the pins without much pressure.  What I noticed might be useful to understanding the problem you encountered with tubes popping out of the sockets if they aren't set deeply enough.  With the 9 pin sockets and tubes (e.g. 12AX7), the shafts on the tube pins are straight, but the sheaths in the socket have a portion at the top of the sheath which is pinched in.  So when you push the tube in, you will encounter an initial resistance and then push through to where the shaft of the pin is being held by the pinched portion of the sheath.  The trick with these is to push them in just enough so that they are being held firmly by the pinch.  This makes for a minimal contact area.  You'll also want to ream open the sheaths on these types of 9 pin sockets - the stock ones I've seen are always way too tight.

The situation with the 300B tubes and sockets is exactly the opposite.  The sheaths in the sockets are straight, but the pins on the 300B tube have a little 'bulb' on the end.  The idea is that you are supposed to push the bulbous ends of the pins all the way down through the sheath until it pops out of the bottom, locking the tube in place.  The best electrical connection here is to have the bulb at the ends of the pins pushed far enough down into the shaft to be stable, but not far enough for it to pop out of the bottom of the sheath.  This makes for a minimal contact where the sheath touches only two points on the side of each bulb.  You'll also want to lower the contact pressure with these, as the sockets are usually way too tight.  The ceramic 300B sockets that came with my kit had metal spring clips around the sheaths which exerted far too much pressure.  Removing them and carefully bending the arms of the sheath allowed me to get a low pressure fit which was still enough to keep the tube stable in the socket.

If you want to try opening up the sheaths in your 9 pin sockets, it can be done without needing to remove the socket if you have the right size needle.  The straight upholstery needle from this heavy duty needle set is the right size.  Just insert it into the socket, turn it a few times and pull it out.

Ok, I finally got my NAB hub adapters and have listened to my 15 ips tape.  It's an early generation copy of the master tape of 'The Andy Williams Album'.  As it happens, this is one of the first albums I ever bought when I started collecting music some 25 years ago.

So what did it sound like?  The first word that comes to mind is BIG.  Image sizes were very large and the soundstage was, if not bigger, more filled in with the sonic images that were there.  In general, it's clear that there is a higher level of fidelity than what I've been hearing with the less dense tapes.  There are also some issues: the bass and the treble both sound overemphasized - almost certainly the result of using the wrong equalization.  The tape is IEC, but the deck only does NAB.  There was some image instability early in the listening session, and I'm not sure if I've got the speed right.  Loading the big 10 1/2" reels on the deck make it clear that something is out of alignment with the reels.  The hub adapters have a noticeable wobble to them and the take up reel rubs against the tape at a certain point on each revolution.  This time I don't think it's the reels themselves, but the platters that they sit on.  Hopefully, the technician will be able to fix this along with everything else.  And there is some treble harshness coming in from somewhere.

I didn't really find the relaxed, yet euphoric musical experience I'm looking for on this first playthrough, but there is something different about the sound of the tape that holds promise.  As with all these things, it's a long term project.  Next step is to get the deck to the technician.  

[UPDATE]
As it turns out, I had the deck set to 4 track instead of 2 track.  D'oh!  

Listening again, the instability is gone and the bass and the treble now seem properly balanced.  The other observations still stand.  I think there's an information density here that I don't recall ever hearing from the digital version.  If I can get the other issues sorted out, this is really going to be something.  Here's a picture:

Greetings Bill333

Thanks for the tips on tuning the tube sockets.

Sonic is finding the music without the sound of foam acoustic treatment in the room is pleasant.

I found a report at: http://www.endino.com/graphs/ that compared the frequency response of a number of well-known studio reel decks when running at 30 ips and 15 ips. The machines tested were from MCI, Sony, Studer, Otari, Ampex and Tascam. What was found was that in all comparative tests, the machines returned the best low frequency responses at 15 ips. At 30 ips a majority machines in the test showed greater low frequency roll-offs. The high frequency extension at 30 ips was of course better.

A rather surprising find to Sonic given that the low frequency signals will be spread over twice as long sections of tape for a given frequency comparing 30 ips to 15 ips.

For good Zonees interested in this topic go read the link. Sonic wanted to reproduce the article here but the number of graphs to insert will have been cruel and unusual punishment to Michael and whosoever helps him with putting up the pix on this site.

Sonic

The tape deck is at the technician for recapping and calibration.  I may have it back in as little as a few weeks, so I'll have a report on the sound at that time.

In the meantime, I've gone back to working on the digital end of my system.  I finally finished the rewiring job I started months ago on the Aune's transformer, I plugged it in and everything went sideways.  The lights on the DAC blinked on once and then stayed off, the transformer started humming loudly and then started smoking 30 seconds later.  I quickly unplugged it, but the DAC is dead.  In post-mortem analysis, I expected to find that I had the wires switched, but the wiring was correct.  I really don't know what caused the meltdown.   Sonic, it looks like you made the right choice to leave the power supply alone.  

It's too bad, I was looking forward to comparing it to the Altmann and the other systems I'm working on.  Although I was never particularly enthused about the Aune - I thought it sounded much like other sigma delta DACs - it had a very relaxed character to it that one rarely finds in a piece of equipment.  I could replace it, but I have so many digital related projects on the drawing board that I don't know when I'll have spare money for it.

Over the next months, I'll be trying out a radically simplified digital transport, the Sonore Microrendu, and upsampling Redbook CD to  DSD512.  Should be interesting times.  

Unfortunately, progress on the tunable room has been slow lately.  I'm realizing that I really don't have the time and energy on weekends to get the ball very far down the field.  I'm going to take some days off of work to spend putting the room together, but it will have to wait until work settles down a bit.

Hi Bill333

A pity what happened with the AUNE. Good thing nothing happened to worsen the destruction.

Speaking of digital projects, have you ever tried the Audioquest Ultrajitterbug or those USB and switch-mode power supply electrical grunge cleaning devices from iFi?

Sonic

Hi Sonic,

I don't have any experience with the Audioquest Jitterbug or any of the iFi products.  But since you brought it up, I noticed they make an S/PDIF iPurifier which I may give a try.  So many interesting things, so little time...

Hi Bill333

Sonic saw this on monoandstereo:

What I cannot understand is when people isn’t told the plain truth – i.e. why selling FLAC or hi-rez 192 khz files on costly reel to reel tapes or vinyl without quoting this feature… plainly, honestly, as is?

There is nothing wrong doing so, folks!

Nobody dares blaming about the pro-photographers using their film-fed Hasselblads’ in studio, then scanning the 6 x 6 slide-film and heavily Photoshopping it in post-production job… so things go!

Only, things should be made crystal clear, honestly – i.e.  shouldn’t be analog vs. analog vs. analog or analog vs. digital… but quality vs. non-quality/average (recordings, music, whatever), only.

Word of mouth – fortunately – works quite well and gossip and so-so practices of (ugly) people not saying the source and dubbing/mastering methods (even, in worst cases, declaring as 100% analog tapes their FLAC-sourced music onto reel to reel tape) widely circulates among the die-hard music and audio lovers.

Beware!

Others try to highlight their job as further improving original recordings.

Abbey Road Studios spent a lot of ink explaining their approach in their vinyl discs reissues series – my mentor Baron Tim de Paravicini cleverly and wittingly confutated their practice where, in few words, the original spliced ¼” master-tape is simply unseen in the remastering studio, as only a cleverly made hi-rez file is then taped on an Ampex ATR machine and used to get the lacquer from the Neumann lathe.

Right or wrong as a process, that’s it.

[For full article go to: http://www.monoandstereo.com/2016/12/analog-vs-analog-vs-analog-vs-analog.html#more ]