[Silent One]

 
 What receiver do you have?

I have the diminutive 

 Sansui G-22000
Sadly, it's been in storage the past few months. Along with 

 the rest of my gears.
 

Silent One has the most amazing Sansui G-22000 monster receiver.............

You are kind. 

 

 

[moodyrn]

  I'm offered Kenwood KA-907. Anyone used this beast? Does it have "unobtainiums" ? Planning to get HE-6. Wondering about synergy with Kenwood. Heaphone out adequatelly strong or speaker taps?
Now listening to recabled HD650's on Yamaha Cr-600. I love this combo except of hiss which i get with my sennheisers. Other than that, it trumped my Schiit Lyr on all corners..
 
Thanks,
minionas

 
I did own this lovely beast for a while. And yes it is conservatively rated. That 150 wpc rating comes in at an extremely low distortion(.0005 if I remember correctly). And at around .05% distortion, it will have no problem hitting over 200 wpc rms. One owner compared the drive capability to his sx1980. I can't confirm if that's true, but it is a powerhouse! Sonically speaking, don't expect it to warm up or color the music in any way. This is one of the most neutral amplifiers I've listened to and it's a true "wire with gain" amplifier. In that regard it reminds me a lot of my fisher 500c. It's also brutally revealing, and super detailed, and the ultimate truth teller. I will have to respectfully disagree with Claybum on the drive capablitity of the headphone output. It's plenty powerful enough to drive the he6 to moderate levels. But as you increase the volume, they will began to looes their composure a bit. But on other hand, the preamp is just outstanding. It's as good as a stand alone preamp. This thing has to ability to drive sensitive iems while providing an extremely quiet background at the same time; still having decent range on the volume knob. That is quiet a feat when you look at it's powerful enough to drive the he6 to moderately loud levels. So there's no need to ever have to use the -20db button to lower the gain.
 
This also mean you can drive the he6 using the speaker taps with an equally black background, and still have a good range out of the volume knob. The volume knob itself is also impressive. It can be used as a murder weapon literally. It's a solid heavy piece of milled aluminum and probable weighs a few pounds by itself. Like Claybum also stated, the build quality is just second to none. Overall it easily surpasses the sx1250/1280 in the sound department which is no small feat.  But it is extremely hard to work on, and most don't even want to touch is. So finding someone to restore it will be extremely difficult.

 

[AWP3888]

 

   
I was just wondering that as well.  Looking at a rather aged schematic for this amp for example, I think it's using 680R 1w resistors to the headphone socket.

 
In theory you would use the same resistor that is in the amp now (only better quality).  You could just pop the top and read the color codes or measure.  I don't even think you should have to lift one end to measure, as the jack end should be open without phones plugged in.

 
 
To that: it seems that the SX-580 has some noise floor issues above 50% volume (output from the Headphone jack).
 > Is that something that might be resolved, in-addition to the sound quality, by replacing the Resistors ?
 
I do plan on preforming a full DeOxit cleaning on the controls and the internals before I put this into "production" but if anyone has some good Ideas on addressing the noise floor issue that would be appreciated.

 

[CJG888]

I'd also stick to the stock values. At the time this amp was current, headphone impedances varied widely (from 8 ohm Japanese models with cone drivers to 600 ohm Sennheisers and Beyers).

Oh, and I'd also check the PSU reservoir caps before powering up. It's an old amp, and electrolytics can leak or dry out over time....

 

[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

 

[PhoenixG]

  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.

 

[lithium1085]

  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.

 

[417457]

   
I did own this lovely beast for a while. And yes it is conservatively rated. That 150 wpc rating comes in at an extremely low distortion(.0005 if I remember correctly). And at around .05% distortion, it will have no problem hitting over 200 wpc rms. One owner compared the drive capability to his sx1980. I can't confirm if that's true, but it is a powerhouse! Sonically speaking, don't expect it to warm up or color the music in any way. This is one of the most neutral amplifiers I've listened to and it's a true "wire with gain" amplifier. In that regard it reminds me a lot of my fisher 500c. It's also brutally revealing, and super detailed, and the ultimate truth teller. I will have to respectfully disagree with Claybum on the drive capablitity of the headphone output. It's plenty powerful enough to drive the he6 to moderate levels. But as you increase the volume, they will began to looes their composure a bit. But on other hand, the preamp is just outstanding. It's as good as a stand alone preamp. This thing has to ability to drive sensitive iems while providing an extremely quiet background at the same time; still having decent range on the volume knob. That is quiet a feat when you look at it's powerful enough to drive the he6 to moderately loud levels. So there's no need to ever have to use the -20db button to lower the gain.
 
This also mean you can drive the he6 using the speaker taps with an equally black background, and still have a good range out of the volume knob. The volume knob itself is also impressive. It can be used as a murder weapon literally. It's a solid heavy piece of milled aluminum and probable weighs a few pounds by itself. Like Claybum also stated, the build quality is just second to none. Overall it easily surpasses the sx1250/1280 in the sound department which is no small feat.  But it is extremely hard to work on, and most don't even want to touch is. So finding someone to restore it will be extremely difficult.

 
Hi moodyrn,
 
Thanks, for very informative post! So i think temporally HD650 are super match for such detailed neutral amp..my yammy is also more detailed than my recently sold Lyr and i like it a lot.
Will see how it goes with the seller, what condition it is.. price is ~720USD..

 

[moodyrn]

That's a decent price. Given it's rarity, prices seem to be all over the place on the rare occasion one do come available. I've seem them go for as much as 1400 and as little as 600.00(very beat up for that price though). So if it's in good condition, that's not too bad. And yes, it should really be a great match for the hd650. I hope all goes well with the seller. I would like to own one again to test my skills at doing a restore since I've become halfway decent at it since selling mine.

 

[pedalhead]

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...

 

[Magick Man]

I need another receiver/amp like I need a hole in my head, but I found a Pioneer A-27 integrated in Florida recently. It seemed to work fine but I had it shipped directly to my electronics guy for him to check out thoroughly. When I told him about it he became more excited than I was (which is saying a lot).

 

[Oregonian]

I need another receiver/amp like I need a hole in my head, but I found a Pioneer A-27 integrated in Florida recently. It seemed to work fine but I had it shipped directly to my electronics guy for him to check out thoroughly. When I told him about it he became more excited than I was (which is saying a lot).

Congrats!  Can't wait to see the pics of it..............

 

[Oregonian]

  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...

 
Congrats!  That's a beaut...................

 

[pedalhead]

   
Congrats!  That's a beaut...................

 
Thanks mate. It is indeed lovely...even more so in the flesh.  The seller has agreed to a £50 refund to cover the damage, which I hope will cover a decent repair (I paid £235 for the amp).  Cheers.

 

[moodyrn]

Congrats on getting it mostly intact. From the pics it looks like a fairly easy fix. It is a really nice looking amp though.