[pedalhead]

Cheers!  It deserves a good repair I reckon..too pretty for a bodge, so I'm gonna look up a decent cabinet maker & see what he/she quotes.

 

[dogwan]

  Hi guys.  Well, my Luxman SQ-507X arrived today.  Unfortunately, it was the victim of an idiotic delivery person.  We'd popped out for a short bike ride & returned to see the box left outside the house, in plain view, in the flippin' RAIN!  Not only that, but the box was clearly labelled "THIS WAY UP".  No prizes for guessing which way it WASN'T up.  Unsurprisingly, there's damage to the wood surround 

...
 
   
 
 
Gutted, as otherwise it looks pretty decent...
 
  
 
I let it warm up a bit & plugged it in...phew, power light comes on.  Then I tried a feed from my Geek Out & plug in some sacrificial ear buds...right channel not working 

.  After a bit of troubleshooting, it fortunately turned out to be the 3.5mm to dual phono cable I was using...phew!  
 
Anyway, a brief listen through my HE-560s...wow...a gobfull of power!  I also had a quick listen through my Sonus Faber Walls...beautiful...although requires the attenuation switch to be enabled or the noise floor is quite high and I can only turn the knob a few mm.  The pots and switches need cleaning for sure as there are some intermittent crackles and balance issues, but I can tell this is going to be rather special...

Lovely amp there!
 
If I were you I would open it up for a visual inspection even if it is working. That broken wood indicates a pretty rough journey. Look for loose boards and especially heavy items like transformers that might have flexed their mounts. I have a Nakamichi TA-3A that arrived doa (not a sale, so no recourse) and it took me a long time to track it down to the small transformer breaking all of its solder pads free. The dent in the back corner should have been my 1st clue. After repairing the transformer it would power up but still no sound. A couple larger resistors on main amp board were stood off the board for heat dissipation and the same thing, they had broken their solder pads free from the force of whatever hit it took. Even so, everything "looked" good from the top. 

 

[dogwan]

How about a little MCS love!
 
Last night I changed things up a little. Normally use my Matrix M-stage w/ Fostex T50rp's in the bedroom for HP listening. But I decided to try my AKG K-400's on the MCS. Don't know why I've never tried this out before. Great synergy and way better bass with the AKG on this little 20w amp than the Matrix.
 
-MCS 3823 integrated amp.
-MCS 3723 tuner (both made by NEC)
-Polk Monitor 4's (early version with Peerless tweets)
-AKG K-400 with custom cable and K-701 pads.

 

[pedalhead]

Lovely amp there!

If I were you I would open it up for a visual inspection even if it is working. That broken wood indicates a pretty rough journey. Look for loose boards and especially heavy items like transformers that might have flexed their mounts. I have a Nakamichi TA-3A that arrived doa (not a sale, so no recourse) and it took me a long time to track it down to the small transformer breaking all of its solder pads free. The dent in the back corner should have been my 1st clue. After repairing the transformer it would power up but still no sound. A couple larger resistors on main amp board were stood off the board for heat dissipation and the same thing, they had broken their solder pads free from the force of whatever hit it took. Even so, everything "looked" good from the top. 

Thanks for the advice. Yes I'll definitely be doing an internal inspection but that'll have to wait a few days as we're moving this weekend so the Luxman is already boxed up & ready to travel. Will be giving it a good Deoxit at the same time. Cheers.

 

[harrinj]

I picked up a Pioneer SA-6800 amp yesterday and matching tuner. This is the most lively amp I've heard and I was surpised how light and narrow it is/was but looks great from the front. The fluorometer is certainly unique. Neat little amp indeed. Now to find a 9800... (he-he) 

 

[Oregonian]

Pic of that Pioneer??????

 

[moodyrn]

Congrats that is a nice amp in both sound and looks, the 9800 is still on my short list.

 

[Skylab]

Congrats that is a nice amp in both sound and looks, the 9800 is still on my short list.

Yup, as it is on mine. Someday

 

[nick n]

  How about a little MCS love!
 
Last night I changed things up a little. Normally use my Matrix M-stage w/ Fostex T50rp's in the bedroom for HP listening. But I decided to try my AKG K-400's on the MCS. Don't know why I've never tried this out before. Great synergy and way better bass with the AKG on this little 20w amp than the Matrix.
 
-MCS 3823 integrated amp.
-MCS 3723 tuner (both made by NEC)
-Polk Monitor 4's (early version with Peerless tweets)
-AKG K-400 with custom cable and K-701 pads.

Always been intrigued by MCS especially that monster receiver of theirs.
 Got some orthos from them, but no "components"

 

[BobG55]

Well my fellow Head-fiers I need your advice, if you don't mind.  I can buy a Kenwood KA-907, in good working condition, for $750.00 CDN.  I will offer $700.00 & see but I digress.
I've read a couple of recent posts about this amp on this thread, saying that it's an extremely difficult amp to service.  On the other hand I also read that it's so neutral that it's the closest amp to the 500C sound wise.  So, what to do ?  Is the price reasonable ?  Since it is a vintage amp it could require servicing in the near future & if it's difficult to service .... There's no perfect answer, I realize that but I'd still like to know what some of you think.  
 
Thank you. 

 

[lithium1085]

 

 

  I have always wanted to get into vintage amps and I am happy to say that I have taken the jump recently. I recently obtained a very well maintained single owner Onkyo A7 from 1977. I intend to use it only as a headphone amplifier at present and I was very impressed with its stepped attenuator volume control and the handy muting switch. I believe it outputs 60 watts at 8 ohm
 
I did notice in my first few days of use that the headphone output is causing a weird frequency response from my low impedance sensitive dynamic headphones. I can however adjust for this using the excellent tone controls and I understand that this likely due to the high output impedance of the amp. I  surprisingly noted that I had to play everything at max volume as otherwise the volume is not enough. I listen at average volumes with a passing fancy for more loudness and I would definitely like to have some more volume.
 
As this is my first vintage, I was wondering if this is something commonly encountered? Do you think tapping the speaker outputs is the best way to go? as always any and all input is welcome. 
P.S- before someone asks/speculates the muting button is functional - I have checked it already

 
 

  No, that's not normal. I'd say that the headphone output should be indicative of how the whole amp sounds. 60W should be plenty to knock your socks off. If I had that happening, I'd first check my inputs. I.E. did I plug a line level input into the phono input or is my input level too low. Next, I'd check the pre-power amp jumpers if the amp is divided. Often you will still get low volume bleed-over even without them installed. Third, some deoxit might shake loose something that was in the way of your music. Finally, consider taking it to a tech if none of these things fix it. Between the frequency response problem and volume problem, something isn't right.

 
 

   
I am using the the aux input at present and the pre power jumpers are in position, I will check if they are loose later today. Thanks for the input PhoenixG...I was very surprised with this as well as my HD 598s are not much of a load at all. I will check about the input levels as well. I really hope to get this working soon.
 

 
I had posted about this issue earlier and was not able to respond as I was travelling. I am happy to report that PhoenixG was absolutely right about more than enough power. The Onkyo A7 is now purring smoothly and I am very impressed with its quality. The bass detail on this fine specimen is mind blowing!
It turns out that the issue was my lack of information and attention to detail.
I noticed finally that the monitor switch was on Tape since the time I received the amp and obviously I still had enough headphone output (with distortions) due to bleedthrough at full volume.
Once I put it to source, the tremendous power output kicked in and now I am using it with the -20db muting switching in place. The distortions in frequency response have obviously disappeared as well. I am putting some pictures now for everyone's viewing pleasure. Thanks again for the Help PhoenixG
. 

 

[PhoenixG]

   
 
 
 
 

 
I had posted about this issue earlier and was not able to respond as I was travelling. I am happy to report that PhoenixG was absolutely right about more than enough power. The Onkyo A7 is now purring smoothly and I am very impressed with its quality. The bass detail on this fine specimen is mind blowing!
It turns out that the issue was my lack of information and attention to detail.
I noticed finally that the monitor switch was on Tape since the time I received the amp and obviously I still had enough headphone output (with distortions) due to bleedthrough at full volume.
Once I put it to source, the tremendous power output kicked in and now I am using it with the -20db muting switching in place. The distortions in frequency response have obviously disappeared as well. I am putting some pictures now for everyone's viewing pleasure. Thanks again for the Help PhoenixG
. 

Glad I could help get it back up and running! Enjoy it!

 

[captouch]

  Well my fellow Head-fiers I need your advice, if you don't mind.  I can buy a Kenwood KA-907, in good working condition, for $750.00 CDN.  I will offer $700.00 & see but I digress.
I've read a couple of recent posts about this amp on this thread, saying that it's an extremely difficult amp to service.  On the other hand I also read that it's so neutral that it's the closest amp to the 500C sound wise.  So, what to do ?  Is the price reasonable ?  Since it is a vintage amp it could require servicing in the near future & if it's difficult to service .... There's no perfect answer, I realize that but I'd still like to know what some of you think.  
 
Thank you. 

 
Well, I'm not familiar with that model, but here are the considerations I would think about:
 
If it's original/unrestored, it will require servicing at some point since the caps are >35yrs old.  If you can do the work yourself and it's a reasonably easy unit to access boards to do the work, that's not a big deal.  But if you say it's  an extremely difficult to service, you either better be good/experienced to undertake the servicing, or willing to pay a fair amount of dough to get it serviced.  If you're not going to service it yourself, be prepared to add another $300-400 to your purchase price.  Then the question becomes: is the unit worth $1000-1100 to you?
 
Now, you can use it as is until something actually does go wrong, but you just have to hope that when something does go wrong, it doesn't take expensive headphones or speakers with it.  And then you'll have to make that decision then whether to invest $ to fix it or sell it for parts/repair.  Likely, if you want to fix it, you'll have to invest more than the $300-400 you would have had to spend to restore it while it work working.  Because once something goes wrong, you have to find out what went wrong, fix the root cause and all other components that might have been taken out by the component that failed (such as output transistors or other transistors that wouldn't normally fail on their own), and then maybe recap the rest to avoid it all happening again.  If you're paying someone to do that, you'll be paying for the troubleshooting time as well.
 
This model appears to be a monster integrated with 150W.  Are you planning on running it with lower efficiency speakers or wanting to get to extremely high volumes?  If so, then maybe you need that power.  But if you're just planning on running it with headphones, it's pretty safe to say you don't need that kind of power and you can get by with a lower model and lower price.
 
Also, once you're getting into that kind of money ($700 untouched, or $1000-1100 restored), you're in the territory where you can actually get a 500C if that's what you're really looking for.  Tube units like the 500C ARE generally easier to service yourself. because it's point to point assembled and you can trace the connections visually (vs buried traces in PCBs that become harder to digest).  And on the tube units, there are fewer things to actually have to replace (some can caps, some coupling caps, maybe a selenium rectifier).
 
Plus, a 500C or similar would likely be easier to sell if you wanted to move on to another piece later.
 
So if it were me, I'd only consider it if I really needed the power, were capable of restoring the unit myself, and liked the sound of this particular model.  I've never spent more than about $250 for a solid state receiver for the above reasons, but have spent $300-400 on tube units because I have confidence I can get them where they need to be reliable and resell them relatively easily.
 
Just food for thought.  Good luck in your decision.

 

[Zulkr9]

Can anybody tell me how vintage recievers sound compared to the modern headphone amps and which models are good, I was looking at yamaha cr620 and the cr820. Not sure if they are any good but they are pretty cheap and look good ! 

 

[MinedSafe]

It all depends on the model make and year. Over the years I did restored few. Usually most of them need to be recapped completely. Pots, usually source selectors are a big trouble and sometimes very hard to get as well. Some of the Vintage amps suffer from high THD and noise levels. Some of them might have the transistors taking a last breath and in most of the cases there are unavailable. While u can get the similar ones it wont be the same amp any more. Once u get a good one u can be very happy with a sound. Say I have Sansui A101 witch is a simple and efficient construction for headphones. Easy to modify and easy to fix. I always play with resistors on the headphone out, the lower the resistance the higher the noise, depending on the headphones.
 
When it comes to sound:
 
It be either thin and not to spacious or quite warm and not to airy. Generally u can always modify the sound to suit your tastes but it does take time and money changing cables and capacitors, straightening the paths and disconnecting useless stuff ( loudness ) Most of them are not worth the money just to power the headphones. Look for cheap but well regarded lower models for headphones at the beginning. I can recommend Sansui and Proton. This will get u started and it might be end of the game, as for me. I very happy with my AU101 sound its transparent and well balanced at this stage. Sounds 3 times  better than say Fiio 12 or any other Chinese tube amp within the price range. Can power any headphones as well I never passed 9oc on the volume pot.