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  • HbG
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Amp question.
Today i managed to snag a vintage Marantz 1060. I got it because i love vintage stuff, it looks so gorgeous with all those shiny knobs and pretty letters. It's in good condition, despite smelling smokey the volume knob turns silently, and there is no hum. For the rest i'm an amplifier newbie. Another reason for getting it is that one is currently doing over $140 on ebay and i got mine for less than half of that.

It sounds great, in subjective audiophile terms, i'd say it has more depth and clarity, and more refined highs, but i haven't set it up next to my old amp (a pretty standard Sony reciever). To switch my speakers between the two in a sufficiently quick manner so that i can accurately compare the two wouldn't be easy either, i don't have space for the two side-by-side.

So that's my question, how much does a good amp matter and what and how big are the differences between amps? Can one derive what is a good amp just from looking at the stats, like thd, rms wattage, damping factor, capacitively coupled output.... or is there more magic involved? When googling i always see amps reviewed in audiophilespeak. I never see "This is a good amp because of statistic x". It's this vagueness i'm hoping to see cleared up here.
  • Last Edit: 29 November, 2006, 04:30:40 PM by HbG
Veni Vidi Vorbis.

  • AndyH-ha
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Amp question.
Reply #1
From what I've read on Blind A/B testing of power amplifiers, no one can tell the difference between one amplifier and another, except for the really cheapie and obviously deficient ones with sub-normal frequency response. The blind part is quite important, of course, because when listeners know which they are hearing, many claim to perceive differences, often extreme differences.

  • HbG
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Amp question.
Reply #2
Thanks for your reply. I know the blind part is important, that's why i'm a regular on the scientific HA and not some other hifi forum.

You say power amplifier, from what i gather on the web the Marantz 1060 supposedly has a really good pre-amplifier. Is it true that they do matter or is that unverifyable also?
  • Last Edit: 29 November, 2006, 05:32:51 PM by HbG
Veni Vidi Vorbis.

  • boojum
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Amp question.
Reply #3
Marantz had a great reputation which got worse as they cheapened the product.  By and large they were more expensive than others.  They had the reputation of being better.  What matters is that you have an amp you wanted, you enjoy it and got it at a good price.  Be happy.  What should you care about other folks' opinions about Marantz, unless you bought it to impress other folks?   
Nov schmoz kapop.

  • AndyH-ha
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Amp question.
Reply #4
Differences in preamps probably have a better chance of being detected reliably, but the question is "just what are you detecting?" Those made for low level signals, such as microphones and phono, often have easily noticed differences in internal noise. When something so obvious is part of the picture, it's hard to say whether or not other factors are real (i.e. contributors to the audible differences). Then again, such preamps, especially some microphone preamps, are not always designed to be flat and colorless (the "straight wire with gain") but to impart some particular characterization to the signal.

  • Gigapod
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Amp question.
Reply #5
...
What matters is that you have an amp you wanted, you enjoy it and got it at a good price.  Be happy.  ...

I second that!

BTW, it looks gorgeous. It really has that "retro vintage feel", with bass, treble and mid tone controls, and the "mono" switches.

If you still want to know more about amplifiers, you could start with:
http://sound.westhost.com/amp-sound.htm

I don't agree with or endorse everything the author writes, but anyways it's a good read.

Just one little note: electrolytics don't age as well as other components, so eventually I would recommed you have it checked by a reliable, honest technician.

  • cabbagerat
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Amp question.
Reply #6
If you still want to know more about amplifiers, you could start with:
http://sound.westhost.com/amp-sound.htm

I don't agree with or endorse everything the author writes, but anyways it's a good read.
Rod Eliot's article on amplifier sound is excellent. Certainly worth a read before you read any reviews of amplifiers, or audition a new amplifier yourself.

Just one little note: electrolytics don't age as well as other components, so eventually I would recommed you have it checked by a reliable, honest technician.
I second this one, too. The capacitance of any electrolytic caps in that amp is likely to have drifted far from their original value, and they might also be leaking caustic electrolyte on the board - which could cause problems over time. A decent technician should be able to replace all the caps for a low price - except the power supply ones which might be expensive.
Simulate your radar: http://www.brooker.co.za/fers/

  • HbG
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Amp question.
Reply #7
Marantz had a great reputation which got worse as they cheapened the product.  By and large they were more expensive than others.  They had the reputation of being better.  What matters is that you have an amp you wanted, you enjoy it and got it at a good price.  Be happy.  What should you care about other folks' opinions about Marantz, unless you bought it to impress other folks?   


Well, it was an amp question, the Marantz story was only an introduction. I do like the bling value of the 1060 but that's mainly a personal thing, or at best a sign of good taste. I'm definitely happy with my buy! And I doubt "hey ladies wanna check out my amplifier" will get me anywhere.  For what it's worth, i think this Marantz is from before they cheapened, this model is was made from '71 to '76, although in their later years there was a not-as-good 1060B model lacking midrange controls, which mine isn't. I can't find a date of manufacture on the outside, the serial number is E320235.

 
If you still want to know more about amplifiers, you could start with:
http://sound.westhost.com/amp-sound.htm
[...]
Just one little note: electrolytics don't age  as well as other components, so eventually I would recommed you have it  checked by a reliable, honest technician.

Thanks for the article and the hint on the caps. Since the amp sounds fine to my ears i think i'll open it up and check for leakage and if i can't find any, i'll leave it as it is. Is there any danger in shifty caps in terms of damage to electronics rather than just affecting sound quality? When i turn off the amp it still gives music for a second or two, so the power supply cap is at least still good enough. It also has output capacitors but the bass is fine too, although having a subwoofer i can't compare bass between left and right channels.
The only part i haven't tested yet is the phono preamp. From what i see online it is quite a good one too. Old Meat Loaf record here i come!

Anyway, i already recorded some records with my previous amp and the most audible thing above noise level was turntable rumble (that can be ABXed, right? ), guess that one's in for an upgrade too.
Veni Vidi Vorbis.

  • Gigapod
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Amp question.
Reply #8
...
Thanks for the article and the hint on the caps. Since the amp sounds fine to my ears i think i'll open it up and check for leakage and if i can't find any, i'll leave it as it is. Is there any danger in shifty caps in terms of damage to electronics rather than just affecting sound quality? ...

AFAIK electrolytic capacitors can fail in many ways.
I have seen them pop, bulge, leak or just plain open. When they short they usually take something with them.
If your amp is from the 70's then I would follow Cabbagerat's advice and have them all replaced: 30 years of reliable service is the most one can expect for electrolytics, imho. Your amp will be ready for another 10 years of service (there is the issue of the pots also - better have them cleaned at the same time).
Or you can do what you said you would do, just open the amp and check visually if there is anything wrong, and fix it or preferably have it fixed.
These amps usually have an average number of capacitors of smaller size, and these are not expensive. The real expense in having them changed is the labour charges: removing capacitors and soldering new ones is tedious work, but it still requires an expert hand.
It may take another $50~70 to have all the capacitors changed, but I would say it's worth it, as long as you find a reliable electronics repair shop to have it done.
Just my $0.02, I don't want to spoil your joy with your new amp. 

  • HbG
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Amp question.
Reply #9
Bleh, and i promised myself i wouldn't spend more on audio for a while... I am proficient with a soldering iron but i'd still rather not take the risk. I just know what a hellish job it would be to replace all that.

Anyway, i would assume the only common mode of failure is changes in capacity (a reduction i suppose). What is the risk of the other horrors you mention? I never hear about it.

I opened up the amp and did a visual inspection. There is no bulging or leaking that i could spot. As expected there is one really huge cap for the powersupply and two big ones for the capacitively coupled output, they look suspiciously new compared to the rest of the parts. You can also see the four transistors of the main stage and the crowded preamplifier circuit board bolted in front of it.The amp also definitely belonged to a smoker, given the smell it has inside and the kind of greasy-ish dirt that is on the components (is there such a thing as a parts washer for electronics?). But the volume knob is absolutely fine so i'm not complaining.

I took some pictures too.
Veni Vidi Vorbis.

  • Gigapod
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Amp question.
Reply #10
Bleh, and i promised myself i wouldn't spend more on audio for a while... I am proficient with a soldering iron but i'd still rather not take the risk. I just know what a hellish job it would be to replace all that.

Anyway, i would assume the only common mode of failure is changes in capacity (a reduction i suppose). What is the risk of the other horrors you mention? I never hear about it.
...

I have no idea; not even a guesstimate about the number of failures/year for 30-year old electrolytic capacitors! Heat certainly increases failure rates, so avoid overheating the amp (if you throw a party, don't use it to play loud music all night long).

But taking a quick look at the pictures you posted, I would say that's a rather nice amp, the components look like they are in good shape, and I wouldn't touch it (specially don't touch those trimpots)! Nice big transformer, and the big caps look good too. If the volume pot is good, don't touch it either.

You don't even need to try to remove the dust/nicotine, just leave it as is for now. When you have the time, the money and/or the will, have the small electrolytic caps changed for new ones. I counted roughly less than 50 of them, so the expense should be moderate.

BTW: found this thread here about your amp, one of the persons seems to have the schematics. Ask for a copy, it might come in handy.
And then stop worrying (sorry if I'm the cause) and enjoy your amp!
  • Last Edit: 30 November, 2006, 10:22:38 AM by Gigapod

  • pepoluan
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Amp question.
Reply #11
And I doubt "hey ladies wanna check out my amplifier" will get me anywhere.
Care to provide some ABX results?


The amp also definitely belonged to a smoker, given the smell it has inside and the kind of greasy-ish dirt that is on the components (is there such a thing as a parts washer for electronics?).
I personally use Philips Contact Cleaner (sorry the real name slips my memory). It comes in a pressurized can with a straw. Just spray the parts, wait some seconds, and wipe with tissue or clean absorbent cloth.

It's really amazing. The latest use is to revive a dying Logitech Wingman joystick (the X- & Y-axis tracking is going haywire). The Wingman is restored to full health, and my flighsim-addicted brother even claimed that it performs better that it had when it was brand-new (unfortunately, no ABX results here )

Oh, don't forget to turn the amp off and release all connections before spraying
Nobody is Perfect.
I am Nobody.

http://pandu.poluan.info

  • HbG
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Amp question.
Reply #12
Despite it's 200W power rating this amp actually runs quite cool, it barely gets warm at all, this is all good news, i'm pleased and very happy to know a cap revision isn't acutely necessary, but i will do that at some point. I was worrying for a bit but not anymore now. I prefer worries over an unpleasant surprise at any rate.
I'm not a party boy either, I doubt many HA posters are . Of course i'm not touching anything, because if it ain't broke, i don't fix it! I only wiped the dust from the transformer a bit.

I had found that thread with schematics too, but unfortunately the actual schematics can't be downloaded. I think i'll email the guy, it would come in handy when i have the amp serviced.

Thanks a million for all the replies and the useful info. I do have one further question: In the future i want to get some real hifi speakers (no 2.1 set), now i've read that there is some trouble in pairing speakers with these early 70's amps, and i imagine the capacatively coupled output could cause oscillations in combination with a speaker coil's inductance. Is this true or is it not as important as others claim? If so, what do i need to know when looking for speakers?
Veni Vidi Vorbis.

  • bhoar
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Amp question.
Reply #13
Re: aging/leaking/explosive caps

I've experience them twice, that I can recall.

1. About seven or eight years ago, I was pulling out of the parking lot in my old 1989 Plymouth Colt (aka Mitsubishi Mirage).  Suddenly the engine stalled and a strange plastic-y + cooked-shrimp smell started emanating from under the dash.  Short version:  the ECU (aka "engine computer") board experienced a fatal electrolytic cap explosion/flare-up which ended up burning through the traces underneath it when it caught fire.  Luckily, as the ECU is in a metal case, it put itself out pretty quickly.

Sadly, Plymouth/Mitsubishi didn't stock the part in the US anymore, and I'd have to order one from Japan for $1300.  Plus shipping.  Third parties in NC quoted the repair at $450, if the board wasn't damaged, money back if the board was too damaged.

So, I tried replacing the cap myself, and was successful, but the damage to the board underneath it was too great and it didn't work well at all.  Rather than risk my engine and my sanity, I put the car aside for a few months of calling across the company looking for a salvage unit with the same specs.  Finally found on in Missouri(?) for $125, with $20 shipping.  The weird part was the woman on the phone also yelling at her dogs and telling one of her kids to go find the Mirage/Colt section of the salvage yard and verify the vehicle was still there with the ECU.

Got another year or so out of the car before I decided it was too much of a death trap for the highways and moved on.

2. I had a dual Athlon Gigabyte board that started acting up more and more.  Finally, after fully disassembling it, I noticed that the bank of power-filtering(?) electrolytic caps next to the first CPU were no longer shiny and taking on a brownish-satiny look.  The CPU had been cooled well, but the air flow over the board was probably not so good, so the caps aged very quickly in the high heat.  Since there at least eight of them, and since I knew the direction that was going to go (see above) that board got binned.

Summary: aged electrolytic caps can cause fires/board damage when they fail.  Just FYI.

-brendan
Hacking CD Robots & Autoloaders: http://hyperdiscs.pbwiki.com/

  • Gigapod
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Amp question.
Reply #14
...
and i imagine the capacatively coupled output could cause oscillations in combination with a speaker coil's inductance. Is this true or is it not as important as others claim? If so, what do i need to know when looking for speakers?

If I read correctly one of the posts in the thread about the 1060, the feedback loop does not include the output caps, so I don't think there is any risk of oscillation with "normal" speakers.

...
Oh, don't forget to turn the amp off and release all connections before spraying

Simply turning off the amp is not good enough. Unplug the amp and wait for all capacitors to discharge before using any spray inside it. Also make sure you use a spray that does not leave any residues. And do not direct the spray to the trimpots or volume/tone controls.
Personally I wouldn't attempt any cleaning of the innards of your amp, just leave it as is, clean the outside and forget about the inside.
  • Last Edit: 30 November, 2006, 11:42:20 AM by Gigapod

  • HbG
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Amp question.
Reply #15
Brendan, the leaky caps on PC motherboards is a unique situation, as it was the result of a manufacturing fault in the electrolyte. I've seen it too. Basically the loss of electrolyte would lead to corrosion and loss of capacity, slowly leading to less and less stable power and the associated wierdness.
The mitshubishi mirage story is scary, but given your trouble to get a replacement ECU, hopefully very rare. I know capacitors can go out in flames when overvolted, but for that to happen in an amp other parts would have to fail first.

I think i'll just leave my amp dirty for now, even if i don't like dirty things, i always want everything nice an shiny, i don't want to mess with it and take risks either.  I'll keep the philips contact cleaner in mind though as it may come in handy for other purposes.

As for the speakers, does that mean that it's just like any other amp as far as speakers are concerned? That would ease my search.
Veni Vidi Vorbis.

  • bhoar
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Amp question.
Reply #16
Actually, the reason it was hard to find an ECU (and the reason that the NC company offered the services) was because the ECU death happened more often than it should have with that model. 

Good luck with the amp! 

-brendan
Hacking CD Robots & Autoloaders: http://hyperdiscs.pbwiki.com/

  • Gigapod
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Amp question.
Reply #17
...
As for the speakers, does that mean that it's just like any other amp as far as speakers are concerned? That would ease my search.

From what I read on the Web, these output capacitors will give your amp a "different" sound. But I have no idea what that means, and how that should affect your choice of speakers.
BTW choosing speakers is a very, very personal thing. I was quite lucky in that my first "real" speakers were a pair of KEF 104aB's which I got second-hand. That influenced all my later choices for Hi-Fi equipment. The only thing I can say is: don't buy a pair of "serious" speakers without listening to them first. And buy the best ones you can afford; speakers are a long-lasting investment, good ones can last 10 years or more.

  • boojum
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Amp question.
Reply #18
FWIW - You can plug any 4, 8, or 16 ohm speakers into that amp.  Most likely they will be 8 ohm.  I also have some KEF 104/B's and have had them since about 1984.  They kick ass, run at 4 ohms, doubling the power output of transistor amps, and can absorb 4,500 watts of power per speaker, a tad more than I can generate.  The sound is excellent.  The Brits make great sound boxes, very possibly the best although the Canadians make some good ones, too.

The US makes glorious electrostatics (Sound Lab).

You will have that amp for a while.  If it ain't broke, don't fix it.

Life is good!     

PS - that 200 watt rating is most likely per channel, a little conservative, and is continuous output.  You may be able to peak at twice that.  This is no reason to push it.  Repairs might be difficult.
  • Last Edit: 30 November, 2006, 09:42:42 PM by boojum
Nov schmoz kapop.

  • HbG
  • [*][*][*][*]
Amp question.
Reply #19
Sorry, i haven't been clear. 200W input power but only 30w per channel RMS (which is quite conservative). That is enough for me though.
It suggests that the amp is quite inefficient but it also runs quite cool. It has an output resistance of .08 ohms, so with 4 ohm speakers i'd have a damping factor of 50, that should be enough, right?

Thanks for the advice on the speakers. What i'm a little worried about is that i'd have to test them with my amp, as being different it could be that speakers that sound good when i buy them may not sound that great with the Marantz.

Quote
Life is good!     

Most definitely!
Veni Vidi Vorbis.

  • cabbagerat
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Amp question.
Reply #20
It suggests that the amp is quite inefficient but it also runs quite cool. It has an output resistance of .08 ohms, so with 4 ohm speakers i'd have a damping factor of 50, that should be enough, right?
Here are two very interesting articles on output impedence that might be worth a read if you have some time:
Effects of Source Impedence on Loudspeakers
Rod Elliot - Impedence
Simulate your radar: http://www.brooker.co.za/fers/

  • pepoluan
  • [*][*][*][*][*]
Amp question.
Reply #21
Simply turning off the amp is not good enough. Unplug the amp and wait for all capacitors to discharge before using any spray inside it. Also make sure you use a spray that does not leave any residues. And do not direct the spray to the trimpots or volume/tone controls.
Personally I wouldn't attempt any cleaning of the innards of your amp, just leave it as is, clean the outside and forget about the inside.
Offtopic, just sharing an anecdote:

I once did an extreme cleaning of a motherboard that my dog pissed on (while the computer the motherboard was in was lying -- totally disconnected -- on the ground). I spray blast the casing and the power supply, then dry them under the sun. The motherboard & CPU I dunk into a bucket of clean water, dry with a special absorbent cloth, then I do additional cleaning spray with the Philips Contact Cleaner, quite liberally (spent a whole spraycan). I let them all dry, assembled them, ... and it runs well up to now. Go figure.

Warning: Your mileage will vary. I am not recommending you do this extreme cleaning unless absolutely necessary.
Nobody is Perfect.
I am Nobody.

http://pandu.poluan.info

  • Gigapod
  • [*][*][*]
Amp question.
Reply #22
...
I once did an extreme cleaning of a motherboard that my dog pissed on
...
I am not recommending you do this extreme cleaning unless absolutely necessary.[/b]

Lol!
I would say this extreme cleaning was... extremely necessary!

  • pepoluan
  • [*][*][*][*][*]
Amp question.
Reply #23
I nearly died of a heart attack... and the dog nearly died of a heart attack due to his hearing of my roof-splitting scream of agony and misery...
Nobody is Perfect.
I am Nobody.

http://pandu.poluan.info

  • gaillard
  • [*][*][*]
Amp question.
Reply #24
Since you guys are talking about amps and impedence, I was wondering if anyone would know why a headroom spokesman told me the line out on the micro dac couldn't be fed into the bitheads analog input.  He said it was a "hot" line.  Isn't it just line level?  Is this any different than a soundcards line level output?

Thanks guys and sorry for being a bit off topic =O)