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68.104.11.135
This one came in as "non-functional" from seller so it was a relative bargain. I had planned to use it just for parts but then got it working quite well.
- Replaced all 3 motor start/run caps
- deep cleaning and lubing of mechanical levers and actions
- doxit fader lube baths for all switches (user accessible and internal) and pots
- CRC electronic cleaner spray bath of circuit boards in situ
- replaced both counter belts
- replaced pinch roller
- replaced brake pads for both reels and adjusted spring positions
- adjusted "semi-variable" reel power resistor for correct motor electrical back pressure for FF and REW functions.
- Adjusted reel clutch tension for both reels using spring scales and dynamic setting (reels under power)
ToDo:
Test and adjust pinch roller pressure and capstan motor voltage.
Calibrate the VU meters
Waiting on replacement mic pot (bent shaft), Calibration tape, and NAK-T100 software emulator for testing and adjusting wow/flutter and motor play speeds.
OScope testing of head alignments
Suprisingly, the ESP auto-reversing function works (8 seconds of no signal on all 4 tracks initiates reverse). I forgot I had switched it on and it surprised me when it auto-reversed perfectly.
The electronics on these Sonys seem very robust, more so than the Pioneers. All three Sonys I have worked with have had no audio problems from the get-go. Not like the Pioneers at all with their very common transistor corrosion problems.
Sounds really nice, highs extended and sweet, none of that damn digital grit! Midrange and bass balanced and dynamic. Audio of these Sonys is impressive.
Follow Ups:
Otherwise there will be three of them before you can turn on your scope.
Then four...
I woke up this morning and look what I found in my audio test area!
Back in 1984 my reel to reel deck inventory included Revox B77, Technics RS-1500, Sony TC-588 and perhaps some other small shit.
And look what is happening to me now...
Well I am safe from your affliction because I am too old to last another 30 years :)
Just in the last 5 years I went through 72 machines.
Do you think you still have 5 years? :)
I probably have at least 10 years left, but I certainly don't have the bank account for more machines. At least not until I get my 18 year old through college...
Yesterday I listened carefully to a Columbia 4 track commercial release of a double album tape, and then listed to the exact same on TIDAL.
Each media had some advantages over the other but there was no overwhelming winner.
The tape sounded more open, airy, MUCH more like listening to a live performance in a relatively reverberant hall.
THe TIDAL lossless flac sounded somewhat (not that much) more detailed, with better seperation and definition of instruments, and oerhaos a bit more extended in the highs, and perhaps a bit better defined bass.
But the flac media also sounded less like a live listening event. More like listening to headphones.
I may not be investing much more in buying tapes, but I really like many of those that I have.
Having said that, none of the Sonys sound as good in playback or recording as the Pioneer 909 did. Kind of regret selling it...
It is better made than the Pioneer, but it is much older design.However... a VERY important question here is: is it properly calibrated?
Too many R2R owners simply start listening to their new toys, but the FIRST thing you should do is at least run a test tape and get the frequency plot.
Aging and shifting components can do all sorts of damage to the sound.
Calibration is what I am doing at this moment. Whomever did it before me did very good job, but there is no hard rule there, and you can get different sounds while still staying within the factory specs - people often forget that important fact.
For most consumer decks the tolerance is +/- 2dB, or something like that, which means you can have your highs 4dB above your middle frequencies, giving you brighter sound...
OR... you can have them 4dB LOWER, noticeably shifting the sonic signature.
Bottom line: two samples of the same model may produce TOTALLY different sounds.
Do NOT pass any judgment until AT LEAST that portion of the calibration is done.
On high caliber machines you should be able to keep the frequency response within +/- .5dB across most of the range.
Edits: 05/11/24
I expect you are correct and the decks could all use calibration and various electronic adjustments. There are numerous electronic calibrations described in the SM.
I am planning to obtain calibration tape(s) but I also need to get a frequency counter and a high impedance VTVM.
A distortion meter wouid be nice but probably outside of my budget.
A funny story: I have a Lafayette bulk tape eraser and was using it this week in preperation for some recording testing. But I inadvertently left my wallet full of credit cards close to the eraser as I was doing the tapes.
Yep, went to the coffee shop yesterday and most of my cards could not be read. I wiped the stripes I guess :(
Digital scopes show that information, but even without it you will know - on some tapes they have voice announcements. So don't waste your money on it.
Get a nice digital scope, you can find good ones for under $200 on ebay. I have a bunch of them.
Leave the distortion analyzer for the time when you REALLY know your way. Until then a good AC millivoltmeter is what you need.
Don't buy the "professional" test tape, they are too expensive, you can get very, very good ones for 1/2 cost, I have them too.
I have a couple DSOs, one battery powered hand held (to avoid grounding shorts) and one bench DSO.
The handheld DSO also has a multimeter and signal generator (but probably not super low distortion or accuracy).
Also have an analog Tektronics scope that works great.
Just today bought the software NAK T-100 simulator but I don't have calibration tape(s) yet.
Can you recommend one available on the Bay that you think could work well with the software T-100?
I am replacing the large caps now and will be replacing the small caps on the first deck shortly. But the circuit boards are soldered to connecting wiring, not socketed, so removing and replacing is a bit more of a hassle. But I have the caps and the excellent Hakko desoldering vacuum gun so it is tedious but not that difficult.
The boards look fragile though so I will try desoldering wicks before the vacuum.
The test tape does not depend on the analysis software you use.
But it does depend on the EQ and speed - do you know what you need in that regard? Since you are in the US I presume the NAB, but then you need to know the speed.
I never tried that software, as in my office I have the Audio Precision system, and at tome I can do everything with just general tools, but I have been thinking about building a Poor Man's AP for my workshop at home.
What interface device are you using? A sound card or an external box?
Interface is Creative Soundblaster Z SE pci card. There is a newer soundblaster card with the ESS dac that ASR tested to have better specs, but the Z SE should be fine for me for now.
The T-100 simulator software can do a lot with it's own signal generator, testing frequency response, distortion, head alighnment etc.
Just need the calibration tape I guess for speed reference.
I am assuming NAB EQ for 7.5 ips tape speed. But I have not seen docs from Sony that specify.
If all goes well will be putting it all together next week, the PC is on its way too.
I have an unused bench in my basement - yes, I know, hard to believe... there is an old PC sitting there, it will be a perfect place for a test system.
When I think of an old PC, I think of the one that I have which is a Pentium 133, running Windows NT Server, and no PCI slots. ;) It still runs word processing and spreadsheets just fine. I think it has a 1200 baud modem in it.
Hopefully, yours isn't that old!
Maybe be mentally prepared to deal with compatibility/upgrade issues with your new sound card. Just fyi.
*********
We are inclusive and diverse, but dissent will not be tolerated.
It is amazing what you can buy today for $125.
but you'll be lugging decks up and down the basement to test them?
that will get old quickly...
There are no decks on the main floor (we have a single story home), it is my wife's area, except for my office there. :)
I have a 2,500 sq foot basement, part finished with a nice audio room, other finished area and then about 1,200sq foot workshop, with benches, machine tools, etc.
It is a walk-out basement, which makes moving in and out heavy professional decks possible - I use my garden tractor with a cart to bring them from the driveway over the lawn to that door, so heavy stuff doesn't have to go through the clean house portion. :)
While down there I can roll them around easily - something I often do.
I would have to add a balanced sound card, but that is not such big deal. Adds to the cost, though.
Will do. I will post my initial experience testing with the software within the next few days. Certainly there will be a learning curve for me since I have never before attempted such work with tape decks.
And I will go for a better spec'd sound card eventually, although the Z's circuitry likely far exceeds the specs of even a pro tape deck for distortion, frequency response, etc.
First testing after matching levels between deck and software.
I ran two dests, THD and Frequency response, using 7 1/2 ips, normal bias setting, Quantegy 456 tape.
THD hovered around .3% at 400hz which I believe is the only frequency the software can generate for THD test. I did not make a screen shot of that test.
The screen shot here shows frequency response sweep function plot, deck recording in forward direction, so this sums the distortion from recording through playback electronics of the deck. I do not have a calibrated tape yet so I cannot test playback seperately I guess.
Plot is about what I expected based on what I heard from listening to tapes on this unit (decent bass, rolled off highs) and prior to any recording/playback electronic work or head alighnment.
I will look at the SM and see how I can test the different recordng and playback electronics independantly to see where any problems might be. Certainly .3% distortion at 400hz would not be up to spec...
...did you get it plot two channels on the same screen?
I installed it but had problems with the sound card, doing it all in the background. The first card did not fit, even though it was supposed to. The second one had bad channel. This one is working but I only get one channel on the screen.
yes, the screen shot I posted of the plot shows two channels. I do recall in the help that if you are using a sound interface that has more than two channels in hardware there is some special configuration you may have to do of the interface.
"sums the frequency response error" would be more clear I guess than "distortion"
I ordered a PC and it should be here in a couple of days, then loading the program, and I am looking at this sound card:
I like it because it has balanced ins and outs, and the price is not bad either. Not sure about its compatibility yet.
By that time you will have gained plenty of experience, so be prepared to advise. :)
Looks like a great card for this work. The docs included with the T-100 software are quite good in my opinion.
Anyway for me the hard part is still to come: figuring out how to make adjustments and repairs to improve the performance of the Sonys so they are up to spec.
Would have been nice to still have a 909 for comparisons with the Sonys. I bet no contest...
And I am pretty sure no matter how fast I run, you will end up ahead :)
Looks like you've got your work cut out for you to get to this performance:
:)
This is a Stellavox sp7 that I used regularly, many years ago. It was custom modified by Georges Quellet and John Curl. Sure wish I could find it now!
*********
We are inclusive and diverse, but dissent will not be tolerated.
My 909 sounded so good I bet it would be close to the Stellavox. But I sold it :(
and there is a Stellavox on the bay right now for only $35K.
You should grab it :)
He was talking about the portable SP-7, not this stationary beast.
LOL, I am done unless I maybe find a new one still in the box.
Victor, what do you think about baking tapes? I have about 150 reels, all at least 40 years old,many older, many Ampex. They should all be baked right? Supposedly Ampex corp actually released a technical article describing the process to make their tapes playable again.
I did have a couple already disintegrate on the machine. Kind of a mess.
What do you do to deal with shedding?
I have some experience with this. Before building my tape baking oven, I looked into the issues quite thoroughly. I have many old Ampex 406/407 and 456 tapes, as well as some others (BASF, Maxell, TDK).My oven is all wood, with a Lucite window. Two 100 watt light bulbs, two dimmers, two thermometers, and one small computer-type fan, all strategically positioned. I can bake two tapes at a time. In general, for 1/4 inch tape, I do it at 130 - 135 degrees for about four hours.
Some important things to remember:
The SS problem is related to certain "high output" tapes. They absorb moisture from the air, making them "sticky". Not sticky to the touch, but sticky when running over the tape deck heads, rollers, capstan/pinch wheel, ... :(
If it's an important tape, DON'T run it to see if it's sticky. You'll ruin it. Adjacent layers of tape may stick together and peel oxide off.
Acetate tapes (generally older than about 1970) don't have this problem. Do not bake acetate tapes. You'll ruin them.
In general, tapes which weren't considered "high output" also don't have the problem. The problem stems from certain binder and oxide formulations. I've seen (many years ago) a list of tapes which are or are not affected. Sorry, I don't remember the website, but you can probably find it.
Musician Wendy (Walter) Carlos has a link to to tape baking on her website. Also, there's a page about it at www.youramerica.net.
HTH
*********
We are inclusive and diverse, but dissent will not be tolerated.
Edits: 05/09/24
thank you, yes the info is helpful!
Baking is the last resort measure, when you must play that tape at least once, so you could dub it. It might bring an improvement, but only a temporary one.
In some cases it will actually make the tape literally fall apart.
So get rid of them.
I don't deal with it, I don't need any more complications in my life. I recently dumped three brand new, unopened Ampex 10" tapes, just kept the reels and the boxes. This is sad reality. So I only use good stock.
If you need inexpensive but good tape to record on your Sony, buy some 7" BASF reels that come in their gray plastic boxes, it is great, does not shade and can be had for pennies.
[[ when you must play that tape at least once, so you could dub it.]]
yes, that's my need. My tapes for the most part are commercial releases of classical music, seems 90% on ampex.
I've had two of the last 10 dub attempts shed leaving just the clear plastic tape remaining! Does look humorous though...
My tapes are irreplaceable so I will do whatever it takes to dub them. Then they go onto EBAY I guess...
I don't plan on recording on the Sony's unless I can obtain better recording quality tham my tests indicate so far. Definitely not in the same leagus as the Pioneer 909 for recording.
I do intend to do some electronic work on the boards including replacing caps. But I am doubtful I will ever get satisfactory recording quality from the Sonys.
With the 909, I could switch back and forth between source and tape playback while recording and could not hear a difference if level matched.
I can't find a way to level match between source and recording monitoring
with the Sony's but there is a clear loss of quality in the recording...
...that it might literally fall apart, I have seen that happen during baking too, so be prepared for that.
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