EQUIPMENT HISTORY:
Everything I am describing below is IMPORTANT, read it please!
This amplifier is part of my "collection" of all things audio, both professional and consumer gear. I like to listen to all types of audio equipment, look inside and see the build quality and just appreciate the engineering skills (or lack of) in the early days of audio equipment.
Since the early 1990's this amplifier has been sitting in the storeroom of my previous business. We dealt professionally in the world of post audio production but my personal interest is anything of quality that is analog and vintage. I don't believe I ever turned this amplifier "ON" as I was far too busy to play around with all the consumer equipment I had collected as 'interesting'.
I cannot possibly use everything I have and my professional activities always took precedent, so this amplifer (and a LOT more gear) sat in the storeroom waiting for me to "come a callin" - I never did ... too busy
Well, my now wife says "for goodness sake, get rid of that mountain of gear" so them's my orders ... out they all go.
This equipment does have an "issue" (or more) - my description is extremely detailed and I leave it up to the reader to make their own judgement with regard to what servicing work may be required and whether the effort of servicing the equipment is worth it. In my opinion (and many others) this is classic quality from the 1960's ~ 1970's period and the current asking prices reflect this .... take a look HERE to see what people are offering these for right now
After taking a good look around inside and making some very basic measurements and observations, I have determined that this amplifier NEEDS ATTENTION.
Servicing electronic audio equipment skills will be required for this servicing or throw in a bit of carpentry if you wished to fully restore the wooden outer cabinet of the amplifier to pristine condition.
Personally, I don't have the time or the inclination for service work these days (I am worn out after working in the electronics field for 50+ years and I am completely 'over' the servicing side of things) so to be frank, the task of bringing this equipment back to full operational condition is for the buyer to take on.
This equipment is very old and considered 'vintage' in the world of electronics, although it does post-date vaccuum tubes, but only just!
There is no warranty, there are no returns with this equipment, read my description and have a good think about this amplifier, she's a beauty but ask yourself this ... "do I have the skills to fault-find and repair this amplifier?" I am not a consultancy service and will not participate in an online technical fault finding session!
SONY CORPORATION (JAPAN) have been in the electronics 'game' for many many years, producing both professional and domestic products. Kids these days only think of SONY when it comes to gaming equipment, SONY are far more than a 'gaming product' company.
Their major area of design and production has always been professional equipment in the broadcast, video and music industries and even today, a walk around just about any broadcast studio or video/audio production facility will have SONY badged equipment in use.
SONY Corporation knows how to design and manufacture very good equipment and when they ventured into the domestic audio market, this was no exception.
Solid as a rock, extremely well laid out and engineered - this equipment is like the 'Studer of Japan'
This amplifier left the factory in Japan during the 1960's and was right at the forefront of the 'new fandangled' transistor age - it is discrete semiconductor based (Silicon not Germanium with no integrated circuits at all)
So, enough introductions ... here is the detailed description of what I have to offer
SONY - Stereo Power Amplifier
Model: TA1080
Left the factory in 1966
Power output 30W RMS per channel
Frequency response 30Hz ~ 100KHz
Maximum THD 0.15%
Damping factor 40
S/N ratio 70dB ~ 80dB (depending upon the input)
Drives 8 ~ 16 Ohm loudspeaker load
Five inputs: Phono 1 & 2, Auxiliary, Tape, Tuner
This amplifier has some quirks in the design, in particular the Bass & Treble controls are SEPARATE for each channel
Input selection switching is unusual ... 3 way rotary switch with an adjacent lever switch
The rear panel has additional rotary controls for the AUX and TUNER input level control, so that you can have various audio sources of different levels which can be adjusted to sound at the same level from the amplifier.
Watch out with these rear controls! When testing, I didn't realise the rear AUX control was fully off (initially) so I had no audio at all.
GENERAL CONSTRUCTION:
This amplifier is original. These were released in a strong all metal casing which slips inside a veneered timber outer 'skin' - I am supplying this amplifier in the same manner.
The outer wooden case is plywood and the veneer is REAL, FAIR DINKUM wood veneer, not that fake plastic stuff! There is no varnish or top coating applied so it is easy to clean up and produce a "like new" appearance. The four base feet are all rubber.
Easy to access the inner metal casing and open it up ... just remove the 4x bolts which go through the rubber feet and then the inner metal case will slide out.
FIRST IMPRESSIONS ... Very clean inside, no obvious component stress (burning etc) and the equipment looks completely untouched inside since 1966! Actually I can see someone has changed a pot (VOLUME) upon closer inspection...more about this further down in the description.
LOOKING AROUND INSIDE ...
For someone like me, I love this layout - so well organised, logical and good engineering which I don't often see in domestic equipment these days, perhaps the only equipment of a similar engineering level is that from ROTEL which I had recently (didn't even have time to advertise it, someone came around and bought it immediately!)
So, taking off the top section reveals the basic construction, all printed circuit boards are vertically mounted and each 'section' is separated from each other for both physical support and shielding. The purpose of each board is easy to determine although a Service Manual is available from me anyway. The case and all internal metalwork is steel or tin (ferrous) except the long Black coated power output heatsink and the front fascia with is thick, solid Aluminium.
The layout is superb, with the heaviest item (the lovely totally enclosed Black AC power transformer) being placed towards the rear in the centre, this creates a unit which is well balanced when being moved around. Don't you hate it when an amplifier has the power transformer (usually the heaviest item inside) off to one side so that when lifted it feels 'lop sided' and more difficult to carry around safely. A well balanced case also evenly spreads the stresses where the various sections of sheet metal join.
This lovely power transformer is multi input voltage capable and most sensibly, changing the voltage settings is made using an INTERNAL plug next to the transformer - now that is far more sensible than having the switch on the rear panel. I would hate to count the number of times I have seen amps with the rear AC voltage input switch moved to 110V and then plugged into our AC supply = smoke, bad noises, bad burning smells and if you are lucky, a 'popped' fuse (often too late to prevent substantial damage though)
The printed circuit boards are all single sided, no wire-wrap (which is good but can be a pain to work with) and some point-to-point wiring. Bit of a 'rat's nest' around the front panel input selection control area but it is a 'tidy rat's nest'!
Lovely "old school" cable lacing using REAL wax/cotton based material - that's something you rarely see these days. Interconnecting wires and coaxial cable is all plastic coated though, not cloth covered!
As expected (unfortunately) the smaller wattage resistors are the very old 'cracked carbon' type - not good for long term stability and these could be an issue. There are also quite a few higher power ceramic coated resistors sprinkled throughout the design, these should still be fine. The electrolytics are all ELNA, a good Japanese brand but after 60+ years .... hmmm, not matter how great the caps MAY have been, eventually they go 'leaky', especially those under more stress in the power supply area.
Sad about the trimmer pots used throughout the design, some are sealed and some are 'open track' design so it is very likely the resistance settings will not be correct. These are VERY OLD PCB mounted trimmers, haven't seen this type of trim pot for years ....
Same goes for the multi-gang rotary & lever switches on the front panel, these are of an 'open design' so a good clean is most likely needed. In fact after my rudimentary tests, I strongly suspect the input selection control area needs a very good wiper/contact cleaning session. At least the switches are easy to access for cleaning of the wipers and contacts, even with the 'rat's nest' of hard-wiring around the rotary switches!
The pots are all ALPS from Japan (of course) with the exception of the dual gang pot used for the VOLUME control, this looks to have been changed at some time as it is not ALPS and unlike all the other controls, has a fluted Aluminium shaft, not Brass. I also noted the soldering on the tags of this pot doesn't look too great either - resoldering would be a good idea). All pots look to be in physically great shape, particularly the ALPS which are classic 221-714-12 series pots but I am pretty sure these could do with a "squirt" of cleaner as well. I can see there is internal access (gaps in the body) to the inside of the pot so cleaning with a spray should be uneventful.
I see a few very old capacitors on the rear panel, around the auxiliary output sockets (2 flat pins) is a "grand-daddy capacitor" from NKK, 0.1uf 600V OIL/PAPER capacitor - although this capacitor looks to be in great shape, it could be at risk as it has the full 240V AC sitting across it, the purpose is to reduce EMI being introduced by externally connected equipment such as a turntable or R2R tape deck ... easy to replace if necessary (it is not buried deep inside)
No LED's in this baby, this was well before LED's were in general use ... two Edison screw panel sockets .... these lamps (both are missing) are another quirky thing about the design of this amplifier ... you can read all about this in my 'TESTING' section below ...
The transistors are all early Silicon based devices but OLD, if any replacement was necessary this could be a problem, making it likely an 'equivalent' may have to be used. The large TO3 output transistors are type 2SD45 as an example but I also noticed the small signal transistors (which ALL have Gold plated legs) are 'golden oldies' and some even have a Black top casing, in keeping with small signal transistors from this era.
TESTING ...
I am not about to spend a lot of time taking a look around inside this equipment so my 'tests' were brief but they will give the technically inclined some good information with regard to future fault finding of this equipment - the low asking price does reflect this.
First up, the AC input voltage is set to 240V using the plug next to the transformer.
Applied power, flipped the POWER ON lever switch up ... great! No bad smells, smoke etc!
I then tested some basic voltages around the power supply, the main filter capacitor (2000u/100V) has 77V DC sitting across it - this is ok.
The capacitor C301 near the main filter capacitor (2000u/35V) charges slowly but the highest value measured is 26V, a bit shy of the expected 28.8V - could be a problem here.
I also checked both capacitors in the audio power output stages (1000u/60V) and they have 39V present, pretty close to the expected 37.5V
It is noticeable that SONY have used capacitors with very conservative working voltage ratings, unlike many modern amps which have the larger electrolytics working very very close to the maximum voltages of the filter capacitors (lower working voltages = lower costs)
SPECIAL NOTE - One of the equipment design quirks ...
FRONT PANEL LAMPS
As mentioned in the cosmetic condition report, BOTH front panel lamps are missing. These are both incandescent edison screw base BUT not at all what you would expect! They are powered from the main supply of the amplifier, so do NOT fit 6.3V or 12V, these are supposed to be 100V lamps! In all my years I have not seen many 100V DC panel lamps (SONY part # 1-518-050 for what it's worth) so that will be an interesting challenge OR convert those lamps to a couple of nice bright White LED's with appropriate series limiting resistors.
At turn POWER ON of the amplifier I did check the voltages across both lamp sockets and can confirm that they both have 77V sitting across them - be careful!
Why do I mention these lamps here? Because at 'turn ON' there should be the POWER lamp (Red) alight and also the SAFETY lamp (Green) should be alight - neither are of course (no lamp fitted) so I used my meter to make sure the Power & Safety lamp edison sockets have power - they do, so all is good with the world ... the safety cutout has not been activated.
I am able to supply a good, readable schematic which details test voltage points and expected current flows and the Service Manual (which is 'ok' but not brilliant in detail - just 21 pages only)
The moment of truth .... Power ON, audio source connected to the AUX and a couple of 8 Ohm test loudspeaker systems.
NO sparks, no smells, no burning - Phew!
There is a short delay before you will hear any audio, this is normal (in fact this is mentioned in the Service Manual as it seems this confused people back in the 1960's)
Just wait about 4 seconds (no click will be heard unlike modern amps) and the audio output 'comes alive'
However, I am hearing audio from one channel ONLY and at a very low level - the maximum I could measure was just 1 Watt from the Right Channel. The audio is CLEAN (not distorted) and I was able to check that the Bass, Treble and Balance controls all worked WITHOUT noise when being rotated.
The Left Channel is silent. I mean SILENT - no hum or hiss, just very quiet.
Next I used to good old 'touch the audio input to the driver/output boards' to get a response. In keeping with the great layout of this amplifier, these input points are easy to access, being on either driver/output board in the top right hand corner area (where the coax is connected)
NOW the Left Channel is good, a nice 50Hz hum which was loud.
I also had the same result from the Right Channel audio input but at a much lower level.
Based on these rudimentary tests, I believe the driver & output stages in both channels are fine, the issue is back on the 'front side' boards where the pre-amp circuits are housed OR the front panel switching. I could have reversed the coaxial inputs to each driver/output board and I wouldn't mind betting that then there would be one great channel but still the other will have issues.
I left the amplifier running for many hours with just one channel producing audio and all was good, at least it is stable!
I made no tests to the Phono (turntable) inputs or the Tuner input ....
COSMETIC CONDITION ...
USED
After 50+ years, I was amazed to be truthful!
The outer wooden case is in great condition, barely any scratching and the veneer is not discoloured. All joints are sound and the top Black steel ventilation panel has not corroded.
Just one thing (look at one of the photographs) - you can see where the veneer has been damaged on the rear/left side when other equipment was placed too heavily next to this amp when stored.
Going inside the wooden case ...
The sheet metal top cover is in great condition, substantially protected by the outer wooden 'skin'.
The front and rear panels look great, without any substantial markings
ALL solid Aluminium knobs are present and the solid Dark Brown paddle knobs are also present. The latter are 'push on - pull off' types and the Aluminium knobs use grub screws.
Rear panel connectors are all clean and shiny, as is the Earth connection for the phono input(s).
Power lead is 3 core, properly earthed and has no sheath damage - a standard Australian 3 pin moulded plug is fitted.
While looking around inside I checked for missing screws, all are present.
I hope that someone appreciates what this SONY Amplifier represents from a bygone era and can bring it 'back to life' for their own pleasure or possibly resale.
Keep in mind that shipping of this equipment ANYWHERE around Australia (only) is FREE, fully insured and tracked.
I have a policy 'site wide' that if someone orders items valued over A$75 then I will ship for free within Australia - this option will show automatically in the 'checkout' area
