i own, or have owned at various times, monsters like the kenwood kr9060, the pioneer sx1250 and a yamaha cr2020 and i gotta say that the harman hk730 sounded better than any of them; the lower-powered hk430 may have been even better. as i understand it, in addition to the twin power supply harman was judicious about the use of negative feedback to reduce distortion, which made 'em sound more lifelike than their peers. they also had really good tuners and phono sections. moreover, other than spraying a little deoxit, the hks needed no refurbishing or repairs--they just keep on ticking. also much cheaper, if not as cool-looking, than the aforesaid.
This quote from me is from a very similar thread posted yesterday:
The thing is, any receiver or amplifier from that era is going to need work to perform the way it did when new. Controls and switches have to be cleaned, mechanical grounds (often screws holding circuit boards down) have to be sorted out, filter capacitors in the power supplies replaced, and electrolytic capacitors used for coupling and bypass replaced (as well as any tantalum capacitors used as coupling caps- yuk!). Additionally its a good idea to remove the output transistors, clean the heatsinks and reseat them with new heatsink compound. The bias and dc offset controls should be cleaned as well and then adjusted properly. The bearings in the variable capacitors used to tune the FM should be cleaned and the FM given a complete alignment. The unit should be tested for noise- transistors this old can become noisy.
A word to the wise: semiconductor replacements are tricky to find. Most of them are no longer available, although there are likely replacements. But there are plenty of Chinese counterfeits that you can get easily enough on ebay, but quite often they don’t meet spec and may just blow up when installed. A reliable source of parts is East Coast Transistor Parts who has been around for decades:www.kenwoodparts.com/
Do your homework and due diligence when making a purchase like this. Good Luck!
I am using a re-capped Accuphase E-303x, and find it to be outstanding. While I certainly wouldn't claim that the sound surpasses the best of contemporary amplifiers, I have no doubt that it is superior to many that were manufactured much later.
I do not feel as though I am missing anything significant when I listen to my system , which includes Harbeth P3SR speakers, and a 15+ year-old EMC 1-UP Electrocompaniet CD player.
Ditto on the E-303..... a marvellous bit of ‘70s sound engineering. To complete the era’s “sound”, the system is Luxman PD441with MicroSeiki MA505, and some recently refurbished Mordaunt Short Pageant Series 2, for which I managed to source some original Isophon KK10-8 tweeters. Ah, the sweet sounds of youth!! Whether this “surpasses” the quality of modern gear, as the OP asks, becomes arguably immaterial. ;-)
If you're even a little competent working on electronics, or if you know someone who is, go for it. A lot of gear that old really was built to last more than one lifetime. A good friend recently paid a competent technician to refurbish his father's Yamaha cr 2020 and all that was done was a lightbulb replacement or two, lubed some dials and a good dusting. Caps were all within spec. If you're using it for Lp playback an older amplifier can be incredibly rewarding. Cheers.
I owned a Pioneer SX1250 in the 70's for several years. Used it almost daily. Sounded pretty good with the speakers I had. After some years of use the first thing that went was the FM radio receiver section (folks listened to a lot of FM in those days). I could live with that since my serious listening was with vinyl and tapes. Then, one day, the left channel died. In those days most people just resigned themselves to buy a new amp and scrap the old.
Some of those Japanese amps were among the best that could be had. There is a nostalgic and logical purpose to restore and keep that equipment. But, as some have stated, the capability to diagnose problems and find quality parts is a challenge.
I have much respect for those who have a desire to preserve vintage equipment.
I don’t have the pocketbook for flagship models but some of the most musical pieces I have are vintage Marantz (1060 integrated) and Sansui pieces (entry level au series) .. a couple hundred in new caps and keeps pace in terms of musicality with modern gear. Marantz is warm and fuzzy.. Sansui has punch and definition. Have heard gear literally 20 x’s the price from the modern era that don’t get my feet tapping as much. Mid to late e 70’s era gear was dialed in.. Seems we have lost affordable, decent gear ...
but what about really be surprised by the quality of a 40 years old equipments don't loose in anything for the modern standards?If you can get one really nicely reconditioned, with some choice upgrades like better caps and rectifier diodes for cleaner smoother power, then you might be able to get one to sound about as good as a comparably expensive good modern component.
There's always kind of a zone where two things sound about the same and you wind up taking one over the other based on things like look, feel, reliability, reputation. These classic old amps fall into that category. Get one running and looking good, that alone could be worth it.
If the only thing you care about is sound though, new gear is a whole lot less trouble.
Thanks for the feedbacks from all of you, really appreciate.
I presume that are some laboratory tests made by a experienced technician, that knows how to restore vintage equipments, in order to know if the equipment is delivering his full potential again after the work is done, Is that right?
(I mean, besides the listening evaluation, it’s also possible to verify the performance via some laboratory tests?)
By the way, my knowledge about electronics is limited, but I know what are the capacitors, and understood that is mandatory that after 40 years they must be changed, even if the equipment is in impressive Near Mint condition.
Let me ask you, what are the little components that looks like capacitors but they are soldered on the circuit board in horizontal position? they are capacitors too and also must be changed?
What about the transformer, I understand that they are vital to the sound performance of amplifiers, and some high end gears have custom made transformers, but till now, no one told me if this component also degrade with time and must be replaced too... there’s a test in order to know if the transformer still working optimally?
Thanks to all, best regards!
A couple of weeks ago I stumbled upon a mint conditioned Onkyo M-504 (from the late 80's) on Ebay of all places. It had been sitting in a box in a storage unit for decades. It appears to be virtually new. It plays perfectly without any servicing. I drive it from the variable outputs on a Rogue Audio Cronus Magnum II integrated amp. Those two bi-amp a set of Polk LSiM707's. Shweet!!!!
Also copying something I wrote on another thread a few days ago below. Do not believe anybody that tells you that you absolutely MUST have a complete restoration job that will cost several hundreds of dollars (at least) to replace every capacitor/resistor etc...First of all that will change the sound that the receiver was born with. You can definitely find receivers from the 70’s that still sound wonderful with no work done to them...it is a crapshoot thou. I have no experience with the Harman Kardon listed above simply because they look inferior to their counterparts...so I stayed away. They could sound great thou. The IC CHIPS for FM reception on several Harman Kardon Receivers from the 70's no longer exist...so if RADIO is important to you do your research first (on AudioKarma)
Your best place for info on Vintage gear is AUDIOKARMA....not Audiogon....not even close. Don’t waste your time here. This post would have 50 replies in a week on AudioKarma.
I have over 50 of these mid-late 70’s in stock and have owned well over 100. The worst sounding brands to me are Yamaha "Natural Sound" and Sony receivers. Tandberg is another dog. Kenwood is better than these BUT middle of the pack for most models...exceptions below.
It really depends on what you want to hear. Pioneer and Marantz sound great but far from the highest resolution.
Luxman will give you the greatest "detail". You will hear things with Luxman that will be masked by most of the other brands.
Here are some of my Favorites to seek out.
Best bargains (which sound Better than the best Pioneer/Marantz): SANYO JCX-2900K, ONKYO TX-8500 either version, Sherwood 9910.
Others are Any TOTL Sansui’s like Eight Deluxe (Not Eight), 9000 Models....not cheap. NIKKO NR1415, Kenwood KR-9600 and 9050, Technics SA-800, Luxman R1070/1120.
Pioneer - SX1250, 1010, Marantz 2285, 2325, 2330
I pair all my receivers with JBL Monitors (4412, 4312A, JBL 166)
Hope this helps you get started.
I agree with riaa.
The most important things are the main power supply caps, then any decoupling electrolytics.
Generally this means from around electrolytics from around 10uF on up.
Leave anything smaller, unless it's an input coupling cap, those really do need to go, but cheap and usually only 2 of them.
I'm the fortunate original owner of a Kenwood "Supreme" 600 integrated amp from this period. I purchased this overseas in the Navy back in 1978. I recently had it gone through and re-capped and brought it back to better than factory spec. Plays every day with the original KT-8300, which was acquired at the same time. Still sounds amazing at every listening level...
Taking vintage Sansui amps as an example, there are several guys on Ebay who work on them. There seems to be three camps. The first will “service” the unit, which can mean anything. Unless you know what was done, in some detail, you run the risk that nothing much was done or, worse, that the unit was damaged by someone who did not know what they were doing. (I learned this the hard way.) The second guy will replace only what needs to be replaced to bring the unit up to spec. The third points out that electrolytic capacitors typically have a life of about 35 years, so for vintage equipment built before the mid-Eighties they all need to be replaced rather than wait for the next one to fail. And this is just the beginning of what will be a strip-it-down-and-build-it-up-again project that results in a unit that should be good for another 30 to 40 years.
I have a restored Sansui AU-717 integrated amp (sold 1977-79) purchased from an Ebay seller based in Olympia, WA, who is in the third group. His listing is for restoration services—you supply the rebuild candidate—and my understanding is that he rarely offers a restored unit for sale. His listing gives a detailed summary of the extensive rebuild that he does.
The Sansui is in a horizontal bi-amp setup with a Sherwood S-6040CP power amp (1983) and a Marchand XM9 active crossover. These are both dual-mono amps, and together they easily best the McIntosh equipment I previously used, a MAC 4100 receiver and MC7100 power amp. Due mainly to dual mono, I think, separation and detail are much improved. Along the way I also purchased a used McCormack DNA-125 power amp and McCormack RLD-1 preamp. They were transparent and detailed, but no match for the Sansui and Sherwood combo.
I bought the Sherwood for $125 on Ebay. So far as I know it has not been serviced or restored, and thus may not be performing at its full potential, though it sounds good.
I also have a Harman Kardon 730 receiver in a smaller system in a back room. I bought it from a guy who had brought it up to spec but did not do a full restoration. That’s how I got started pursuing dual mono.
So I guess you could say I am in all three camps—fully restored, brought up to spec, and “as is.” But if anything fails, I will look for a complete restoration.
I think that trying to re-create the original sound is a hopeless quest unless you have the original parts in their original condition—and given what we know about capacitor rot, this would require a miracle. Where are you going to hear the original sound, anyway? The unit that was just pulled out of a box and has never had anything replaced will not sound the way it did when new. If we don’t have an example of how it sounded when new, then talk about how new parts will change the sound is just unverifiable speculation. All anyone can do is meet spec, and if it can be done with parts that better withstand heat or last longer, it’s a win.
I will disagree with the above post about NIB Receivers which I have and have had. If your saying that putting NEW parts will make a 40 year old receiver sound more like it did at the time it was built in the 1970's then just using it directly out of the box AS IS is a ridiculous assessment. Fresh out of the box 40 years later might not sound exactly as it would have at birth but its as close as your gonna get. Let me know when you have over 100 of these things to compare.
AUDIOKARMA is where you go if you want to find excellent restoration services from people who's reputations are in full display with plenty of feedback from other board members about their work. NOT FLEABAY for Gods sake.
It plays perfectly without any servicing.If really NIB and it sat on the shelf for 40 years, its a good bet the filter caps are shot even with no use.
I don't advocate replacing resistors in vintage units unless they are clearly defective. But if you want reliable service **and** also expect the unit to perform to spec, you will have to change out electrolytic capacitors. There's simply no way around that simple fact. All receivers made during this period used electrolytic coupling capacitors and its common now to have to chase the defective ones down. Even if they pass a signal that's not the same as speccing out correctly.
Lot's of very usefull info from everybody, really appreciate, thanks guys.
I was thinking this days, I think a good route to go when searching for vintage amplifiers, it's interesting to look for some mid 80's early 90's equipments, that can be found in near mint condition, this can be a more safe way to find the gears with less deterioration on internal components, and also I noticed that are some pretty nice high end gears from that era, for example: amplifiers like the Pioneer M-73, Pioneer M-90, Sony TA-N77ES, Marantz SM-11, and etc... and the selling prices are relatively good for this devices, even considering the ones in Near Mint condition.
Your not doing your homework. Starting around 1980 COST CUTTING measures became the rule of the day for audio equipment and much of what was made in the 80's/90's has an inferior build quality to the 70's models...which is why stuff from the 70's continues to rise in value. Not saying everything is Junk from the 80's but a large percentage is. Also some of the companies were bought out...like Luxman being taken over by Alpine...so you need to do more digging or you will be throwing money out the window.
The problem with dealing with equipment like this is that it was all built to a budget. Open them up and they look surprisingly similar regardless of brand. Shipping was the main cost- the older units in the 60s and 70s had metal chassis work with nicely done front panels. As technology changed (more ICs, particularly in the output section) and as shipping costs increased over time, metal chassis (and wood cabinetry) gave way to plastic chassis, monolithic circuit boards and controllers to manage front panel controls and inputs.
In a nutshell, the 60s and 70s stuff is easier to service from an access point of view. But these days they are so old that the electrolytic capacitors within (and there are often 100s of them in just one receiver) makes them a poor investment if quality sound is your goal. Sure- they were nice for the dollar when made (which is why they put US companies out of business) and they had good specs on paper that really hasn't changed all that much in the last 40 years, but their day has passed unless its some sort of sentimental value that drives the restoration.
This is not to say that you can't find one that still works. But 'works' and 'meets specs' are two entirely different things.
When i was saying about the 80’s gears, i was thinking about some "gems of that period", discovered recently some really interesting stuff, stuff that do not fall on the concept of cut costs in production, cheap equipments and etc, but thanks for the info about the market changes about 70’s in compare with 80’s.
As someone who has been through blind tests I don't believe in SS amps sounding different. That said, I own a few vintage amps/receivers (Technics SA-500/Pioneer SA-8800, M-72, SX-3800) purely for aesthetics. They sound the same as my newer equipment and I haven't had any problem with them. I do only buy refurbished vintage (the Technics I bought new), so as not to have to worry about bad capacitors, LEDs, etc.
I can assure you that my 50+ 1970's Receivers restored or not do not sound anything like my Dagostino M400 Monoblocks, ARC 150M, Pass XA-25, Valvet E2 or Sit-3. Nor do all those 1970's receivers sound the same as each other....not even remotely close EXCEPT for the ones made by the same brand. Maybe all of your receivers were restored with the same exact parts and thats why YOURS sound the same.