Anyone Have A Onkyo M-506RS
- Thread starter Ynow
- Start date
I recently got an M506RS and P306RS (pre-amp) and the amp is excellent.
See if he has the operators manual!!!
From what I have found the 506 was sold in Japan. It is hard to find an operators manual. None of the free sites have them but you can get one for around $30 from a pay site.
Check the lamps and make sure they all work.
Mine needs the VU meter lights and a couple of the indicator lights replaced. From what I have found the VU meter axial lamp is not easy to get. I have worked with AK member dgwojo for the lamps (he is outstanding). If the VU meter lamps are working correctly they should be amber on warm-up then green when the system is ready (10-15 seconds).
See if the seller has the servo cable that hooks the amp to a Onkyo pre-amp.
Onkyo developed their systems to match with a servo cable. These cables are hard to find and only work with Onkyo pre amps developed at that time. I can't tell you exactly what this cable does but my system has one and it sounds great.
If you don't get the servo cable it will work just fine hooking it up to the pre just like any other amp. There was a thread in AK that showed how to make a DIY servo cable if you get an Onkyo pre.
I won't tell you what I paid for my system but I gave the seller $50 more because I didn't thing he was asking enough. The price for yours is in the upper range. I guess if it is pristine, everything is working, manual and servo cable present it would be an ok deal (I gather it is local pick-up and you don't have to pay for shipping that beast). For reference a pre, tuner, and amp went for $500 on the Canadian site recently. Try to work him down a bit.
If you decide to buy the amp your ears will be the real decider. Give it a workout and see what it will do. Take note of what the seller has hooked to the amp. If your speakers and pre are not comparable quality......
Good luck,
lifer70
See if he has the operators manual!!!
From what I have found the 506 was sold in Japan. It is hard to find an operators manual. None of the free sites have them but you can get one for around $30 from a pay site.
Check the lamps and make sure they all work.
Mine needs the VU meter lights and a couple of the indicator lights replaced. From what I have found the VU meter axial lamp is not easy to get. I have worked with AK member dgwojo for the lamps (he is outstanding). If the VU meter lamps are working correctly they should be amber on warm-up then green when the system is ready (10-15 seconds).
See if the seller has the servo cable that hooks the amp to a Onkyo pre-amp.
Onkyo developed their systems to match with a servo cable. These cables are hard to find and only work with Onkyo pre amps developed at that time. I can't tell you exactly what this cable does but my system has one and it sounds great.
If you don't get the servo cable it will work just fine hooking it up to the pre just like any other amp. There was a thread in AK that showed how to make a DIY servo cable if you get an Onkyo pre.
I won't tell you what I paid for my system but I gave the seller $50 more because I didn't thing he was asking enough. The price for yours is in the upper range. I guess if it is pristine, everything is working, manual and servo cable present it would be an ok deal (I gather it is local pick-up and you don't have to pay for shipping that beast). For reference a pre, tuner, and amp went for $500 on the Canadian site recently. Try to work him down a bit.
If you decide to buy the amp your ears will be the real decider. Give it a workout and see what it will do. Take note of what the seller has hooked to the amp. If your speakers and pre are not comparable quality......
Good luck,
lifer70
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If you do end up getting it, I would check the DC offset at the speaker terminals before hooking it up to your nice speakers...just some good housekeeping.
ciaokatz
New Member
Hello! What is DC offset and how do you check it at your speaker terminals? Is this on the amplifier terminals or the terminal on the speakers?
I just bought the combo P306RS/M506RS on Ebay for $595. They are hooked up to Yamaha NS-A1638 speakers. I'm not too crazy about the sound yet. I seem to have lost some of the high end. I'm comparing these to a carver av set up so maybe my ears are off.
I don't have either manual. The amp has L + R levels which I assume mean the output level from the preamp. Where do you set these? I originally set them at 8 and it sounded like loud mud. I now have them at 5. Is there an optimum placement for these? There is also a Meter Range which seems to mean the display increments on your power meters. This has no effect on the sound, right?
If someone has a lead for the owner's manuals, I'd be obliged. I downloaded the service manual for the M506RS but it was not helpful for what I needed.
BTW, this is my first post on AudioKarma. I subscribe but mostly lurk, lusting after all of the equipment...
Ciao! david
I just bought the combo P306RS/M506RS on Ebay for $595. They are hooked up to Yamaha NS-A1638 speakers. I'm not too crazy about the sound yet. I seem to have lost some of the high end. I'm comparing these to a carver av set up so maybe my ears are off.
I don't have either manual. The amp has L + R levels which I assume mean the output level from the preamp. Where do you set these? I originally set them at 8 and it sounded like loud mud. I now have them at 5. Is there an optimum placement for these? There is also a Meter Range which seems to mean the display increments on your power meters. This has no effect on the sound, right?
If someone has a lead for the owner's manuals, I'd be obliged. I downloaded the service manual for the M506RS but it was not helpful for what I needed.
BTW, this is my first post on AudioKarma. I subscribe but mostly lurk, lusting after all of the equipment...
Ciao! david
ciaokatz
Go to the following link and read the post provided by EchoWars on DC offset.
http://www.audiokarma.org/forums/showthread.php?t=5634
If the link did not work right go to the solid state forum and it is the second sticky post.
With that said, I have tried to adjust the offset on my 506 and am not sure I did it right. In fact I am not sure you can adjust DC offset on this type of amp. From what I have read some type of power amps use a circuitry that doesn't allow DC offset adj.
The service manual has idling current adj., Distortion adj, meter adj, meter zero adj, meter offset adj, and meter level adj but no DC offset adj.
I run my power amp settings no higher than 12:00. I am running some Speakelab WA6's and a pair of ADS L-520. To me the amp sound wonderful.
Not sure if you are familiar with cleaning the voluume, balance, selector, etc. pots and switches with De-Oxit. Do a search and you will find information on how this is done. Cleaning pots, etc. will fix a lot of problems in vintage gear and should be the first thing you do when having sound quality problems.
Do the simple stuff first - recheck you hookups, try a different set of speakers, recheck all the dial settings, etc.
BTW, the meter range only affects reading on the VU meters.
Good luck, if you find an owners manual post it on the digital documents section.
lifer70
Go to the following link and read the post provided by EchoWars on DC offset.
http://www.audiokarma.org/forums/showthread.php?t=5634
If the link did not work right go to the solid state forum and it is the second sticky post.
With that said, I have tried to adjust the offset on my 506 and am not sure I did it right. In fact I am not sure you can adjust DC offset on this type of amp. From what I have read some type of power amps use a circuitry that doesn't allow DC offset adj.
The service manual has idling current adj., Distortion adj, meter adj, meter zero adj, meter offset adj, and meter level adj but no DC offset adj.
I run my power amp settings no higher than 12:00. I am running some Speakelab WA6's and a pair of ADS L-520. To me the amp sound wonderful.
Not sure if you are familiar with cleaning the voluume, balance, selector, etc. pots and switches with De-Oxit. Do a search and you will find information on how this is done. Cleaning pots, etc. will fix a lot of problems in vintage gear and should be the first thing you do when having sound quality problems.
Do the simple stuff first - recheck you hookups, try a different set of speakers, recheck all the dial settings, etc.
BTW, the meter range only affects reading on the VU meters.
Good luck, if you find an owners manual post it on the digital documents section.
lifer70
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markolino72
New Member
m-506rs
i've got one
for me is as good as beautifull
i dont have the pre
its driving my infinity kappa 8 pretty well (tight bass)
the sound has something lovely.
i have try it with a nad 3020, a sansui au-9500 as a preamp its sounds wonderfull, connected directly to my bifrost uber too,
this power amp with right and left levels is very versatile!!!! (no need to have a pre amp)
large soundstage, instruments well defined, tight bass, good harmonics on the mids,it have a big weighted sound if you find one go for it they seems to be rare on sale, 1979 but still in excellent condition in its original state
very good and solid amp.
i've got one
for me is as good as beautifull
i dont have the pre
its driving my infinity kappa 8 pretty well (tight bass)
the sound has something lovely.
i have try it with a nad 3020, a sansui au-9500 as a preamp its sounds wonderfull, connected directly to my bifrost uber too,
this power amp with right and left levels is very versatile!!!! (no need to have a pre amp)
large soundstage, instruments well defined, tight bass, good harmonics on the mids,it have a big weighted sound if you find one go for it they seems to be rare on sale, 1979 but still in excellent condition in its original state
very good and solid amp.
James Harco
Well-Known Member
I picked one up a few months ago. Disappointed that all of the front panel lights were out. So i bought red and green LED replacement bulbs on ebay, very nice replacementl. (recommend amber for start and green for all clear). When I opened it up to replace the bulbes? I noticed half them were fine. One broken fingernail later, after flicking the center solenoid a few times? the bulbs worked again. An hour of soldering later? all the bulbs replaced with LEDs and it looks awesome. I was told by a repair tech that the LED bulbs would be too bright, but the ones I found on ebay are absolutely perfect. I would put this up against McIntosh amps any day of the week. DC offset when I measured it is well below 2vdc per channel. And just an FYI, this is NOT the same as the m-504. It has 8 matched output transistors (instead of 4), 88,000mfd power supply caps (instead of 72,000), damping factor of 180 (instead of 140) and THD rated at .002%, (compare to .003%). Subtle, but noticeable differences.
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Just got a 506rs last night. Looks like one of the lights is out. Haven't opened it up yet. How many bulbs are there? 4 green and 4 red? It looks like without opening it one green is out. Barely noticeable, just one meter is dimmer. Which LEDs on eBay did you get? I see one guy selling a set of four red and green, did you get two of those? And how much brighter are they then the originals you had? Mine is under my TV right now and don't want it super bright. I see some original style green tinted bulbs on ebay right now, thinking of maybe just getting two of those and replacing the dead one and the matching one on the other meter just so there isn't a brightness difference. I see plenty of pics of the 504 internals but not the 506. And I don't really want to unhook mine just to look, rather wait till I need to for replacing bulbs. Oh and besides the minor bulb issue, LOVE this thing. Got the matching p306rs with it, haven't hooked that up yet.
James Harco
Well-Known Member
I bought these, http://www.ebay.com/itm/282182508515, and the matching red (Originally white for relay on, green for all okay). For me? the amount of light is perfect. Can't tell if on during the day, a bit of a soft green light at night. And FYI, you should replace all of them at once. Incandescent and LED don't play well together on the same circuit or so I've been told. It's worth it to replace all of the bulbs at once. Saves you taking it apart again later. Normally the incandescent bulbs will last between 2-3000 hours while the LED's should last 100,000 or more. Also, make sure the LEDs are facing "down" towards the meters. (yes, 4 safety relay on, 4 normal power).
Perfect, thanks for the info.
This is a quote from a different web site-"These use Onkyo's proprietary 'Super Servo' circuitry (with included special patch cords) to (as I understand it) send a difference signal to the output to ensure it doesn't add any distortion from what is received. What I can tell you without reservation is this is the quietest amp I've ever owned and facilitated my selling of my McIntosh MC-7300."
James Harco
Well-Known Member
Haven't been on AK for while, so an update on my Onkyo? it's been 2 years, on full time, 24x7x365, except a few hours while I was in the basement with it during a tornado warning. There are a couple of reasons I leave it on. I can stream to the source over the internet from anywhere in the hope it might keep "bad guys" guessing. I can listen to it at night or in the the morning without having to get out of bed. And ages ago, a tech had told me that most wear and tear on components? comes from the powering on and off, including thermal expansion of the PCB (not the same for tubes, which are more like lightbulbs). Fingers crossed, two years later and it's one of the best amps I've ever owned.
James, would you happen to know if the side panels on a M-504 and M-506RS are interchangeable?
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Thanks for the help. I had a M-504 before and I always regretted selling it; I don't think it has the amber lights like the M-506RS has because I did have to replace the bulbs once and I only saw four green bulbs. I actually like the green better than the blue so I ordered 4 green LED replacements not realizing that there were also 4 amber bulbs that need replacing so I ordered 4 more red LEDs as I didn't see any amber LEDs on Ebay.
I just bought a M-506RS on Ebay for $575; seems like they keep getting more expensive every year. I was a little leary about buying the M-506RS as I really liked the sound of the M-504; I just hope it sounds as good, but I do like the level controls on the M-506RS. It is really hard to find any direct comparisons between the M-504 and M-506RS, so I'd really like to hear from anyone that has owned both of these models to let me know how they compare and hopefully reassure me that I made a good decision to go with the M-506RS. These are the differences between the M-506RS and M-504 that I have been able to find:
M-506RS has four filter capacitors 22,000 uf each total 88,000 uf; the M-504 has eight filter capacitors 9,000 uf each total 72,000 uf
M-506RS has a dampening factor of 180; the M-504 has a dampening factor of 140
M-506RS has Total harmonic distortion: 0.002%; the M-504 has Total harmonic distortion: 0.003%
M-506RS has Signal to noise ratio: 122dB; M-504 has Signal to noise ratio: 120dB
M-506RS has twice as many output transistors as the M-504.
M-506RS has Power output: 150 watts per channel into 8Ω (stereo); M-504 has Power output: 165 watts per channel into 8Ω (stereo)
M-506RS weighs 20.5kg; the M-504 weighs 22.5kg
But I haven't been able to find any comments on how the M-506RS sounds compared to a M-504.
