KGSS Problem

[RockCity]

Here is the system overview.

http://img202.imageshack.us/i/p1020538y.jpg/

The earspeakers connector.

http://img46.imageshack.us/i/p1020516r.jpg/

http://img39.imageshack.us/i/p1020520a.jpg/

The L/R board.

http://img251.imageshack.us/i/p1020509s.jpg/

http://img577.imageshack.us/i/p1020492a.jpg/

The diodes in question.

http://img4.imageshack.us/i/p1020571h.jpg/

The power supply board.

http://img580.imageshack.us/i/p1020498w.jpg/

http://img40.imageshack.us/i/p1020511i.jpg/

The LM7815 in question.

http://img832.imageshack.us/i/p1020568.jpg/

The power transformer.

http://img189.imageshack.us/i/p1020523q.jpg/

The input selector.

http://img826.imageshack.us/i/p1020519n.jpg/

http://img198.imageshack.us/i/p1020533e.jpg/

http://img849.imageshack.us/i/p1020532.jpg/

Lastly, the AC input connector area.

http://img192.imageshack.us/i/p1020517gk.jpg/

http://img831.imageshack.us/i/p1020528e.jpg/

[kevin gilmore]

I was wondering about all the flipped parts myself, as i have an identical

unit with the same revision of the boards. No flipping on the pins of

the regulator. No crossing of the diodes on the input fets either.

Clearly the +15 is not being regulated with the regulator wired like that.

Measuring that voltage would give you the answer, likely +18 or more

and unregulated and filled with hum.

[RockCity]

Hi Dr. Gilmore, I really appreciate your input and it helps put authority behind these questions. I will do my best to describe my reasoning about what I am seeing. I do not have the least experience in DIY but I am a detail-oriented person.

First, I like to point out that the top cover has been installed backwards. Upon receiving the amp a few days ago, I've noticed that the top four hex screws were not flush against the hood. By looking at the top plate, I've noticed the reverse side had larger bore holes meant to socket the screws. Consequently, the wrong side of the top plate was installed for a long time judging by the minor scratch marks. Conversely, the correct side looks brand new and did not have any finger prints before I laid hands on it. I am reasoning that the amp had not been opened recently because of the side of the scratch marks and also because of the direction of the metal bending from prolonged operations.

Next, I cannot explain the purpose of criss-crossing the diodes but I wish to point out that the short intersection black wires are identical in terms of girth and age to the black wires used in other parts of the amp. Coupled with the twisted regulator, both configurations are out of the norm and custom fitted to fulfill some purpose.

I am not jumping to conclusions but I wish for Justin to disclose me more information about the amp and if certain modifications were requested by the purchaser or if exceptions were made.

P.S. Upon looking at the LM7815 picture, I want to confirm that the all three legs are soldered. The angle makes it look like the first leg is not touching the board.

http://img863.imageshack.us/i/p1020577.jpg/

http://img821.imageshack.us/i/p1020576kg.jpg/

[RockCity]

I will reinforce my previous post with more evidence.

Here is the incorrect side of the plate with faint lines that represent very minor scratch marks.

http://img59.imageshack.us/i/p1020585m.jpg/

Here is the correct side with no discernible wear.

http://img854.imageshack.us/i/p1020584.jpg/

Here is the actual unit itself posted by an attendant of the 02/20/11 meet in NC.

http://img818.imageshack.us/i/fe6480ebimg1810.jpg/

Please notice that the top screws are not flush. Note, I purchased the unit afterward in March and was not at that meet.

[Craig Sawyers]

From what I've seen in the pics it is a wonder that this amp works at all!

[Pars]

If I were you I would make the seller take it back... of course I wouldn't have bought it in the first place.

Edited March 15, 2011 by Pars

[justin]

the issues with the crossed wires for the diodes, and the crossed legs on the +15V regulator were to correct board layout errors -- this was a prototype board. this is likely the first KGSS ever built, sometime around the end of 2003. the build quality is obviously not indicative of a current model. i do not remember if the Alps potentiometers were the original volume controls.

by the way, everyone is always the 2nd or 3rd owner.

a while ago Asr was selling a pair of HD600s, and I think he said he was the 2nd owner. Just for fun I traced the pair's history on the Head-Fi for sale forums. I was able to trace it back to 9 or 10 owners before the trail went cold. And the price was only 10-20% less than a new pair...

Edited March 16, 2011 by justin

[RockCity]

Hi Justin, I really appreciate your response. I saw that the serial no. is 1000 and I assume it may be the first unit produced. Alternatively, there is no way that there can be 1000 KGSS made seven years ago.

My question at this point is do you have any interest in restoring this unit? The unit has a humming issue but both channels are operational and do not have distortion. Secondly, the Alp controls need to be updated with DACT pots because balancing is free-hand. Lastly, The volume knobs are very worn but the overall condition is very good.

I want to know if you have the schedule and interest in doing this restoration because I know you are very busy with your life. I ask for your help because I am not sure if the seller will give it to a third party if I send it back.

If you are interested, please give me an estimate and also a turnaround plan. Thank you.

[grawk]

you can call him DannyB, we know who he is.

[justin]

Hi Justin, I really appreciate your response. I saw that the serial no. is 1000 and I assume it may be the first unit produced. Alternatively, there is no way that there can be 1000 KGSS made seven years ago.

My question at this point is do you have any interest in restoring this unit? The unit has a humming issue but both channels are operational and do not have distortion. Secondly, the Alp controls need to be updated with DACT pots because balancing is free-hand. Lastly, The volume knobs are very worn but the overall condition is very good.

I want to know if you have the schedule and interest in doing this restoration because I know you are very busy with your life. I ask for your help because I am not sure if the seller will give it to a third party if I send it back.

If you are interested, please give me an estimate and also a turnaround plan. Thank you.

How extensive a restoration?

[Augsburger]

Just curious, you won't tell who the seller is yet you ask Justin to give you all the history he knows about the amp. I am confused why the secrecy? Usually if people want something like information or help they generally offer something in return. You on the other hand seem to be here doing nothing but asking for members time and expertise.

[RockCity]

1. It needs to up to spec with the current model. Board differences notwithstanding. Put differently, even if it is a first revision it needs to function and perform the same. I'm not suggesting swapping out the boards just because they have errors. Therefore, I'm betting on that these errors can corrected.

2. Floor noise must be corrected. I had your dynamic amps and they are dead silent.

3. ALPS controls to be replaced with DACT in current models. Replace worn knobs with the current ones.

[justin]

in this case the fastest thing to do is just switch the circuit boards with new ones & install the DACTs. then not only is it fully up to spec but better quality too.

[RockCity]

Augsburger, the reason is because the person is not here to defend his side. It is too easy to be blackballed in this industry, especially when people tend to associate malformed hardware with the treatment of the owner or seller. I'm giving Danny the benefit of the doubt that he knew none of this. I don't want people to blame names because I'm not interested. I just want to know if the problem can or cannot be corrected.

Danny suggested asking Justin about the original owner since he does not know. This only became relevant when people said that the machine may be tempered with.

It is uncharacteristic of me to ask for help. I rarely post in discussions on either sites because I feel people tend to be very emotional about their beliefs. I'm sticking out my neck now because I'm interested in learning about this issue. If Justin or Dr. Gilmore does not care about this issue, I will not pursue it further.

[Voltron]

There's just so much wrong with your position that it is hard to figure out where to start. First, enough with the annoying attempts at secrecy. You or we can "blame names" because DannyB's name is already mud here. If the amp's audible problems are so obvious to you, then how in the hell do you think he didn't know anything about it? I wouldn't doubt that he has tin ears, but come on. Second, what's up with the comment that "It needs to be up to current spec"? According to whom? An 8 year old amp -- the first one produced by HeadAmp no less -- isn't bloody likely to be up to any spec. Maybe you are just saying that is what you would want from a restoration, but why would you want to spend as much or more on fixing this thing than you could just by buying a more current model? Third, why would Justin or Kevin give a damn about this issue? There is no issue other than you bought an 8 year old amp that has had multiple owners, has been shipped multiple times, has had the insides fucked around with, and is simply long in the tooth? They shouldn't care one way or the other. There is no reputation issue here, either, which you keep hinting at in an almost threatening way. Maybe you don't post a lot and maybe you are just awkward and overly cautious, but get a grip. Either return the amp to DannyB for a FULL refund from that gear whore, or figure out a way to get it fixed. There is nothing special here, so just be an adult and move on.

[The Monkey]

We don't give a shit about blaming people (at least I don't), but with amps like the KGSS the ownership history can actually help diagnose the problem. Even if you don't know who owned it before the guy who sold it to you, someone here might. That happened with my own little whore of a KGSS. I've said this all before, so I'll stop.

One last thing, I think your paranoia about disclosing the seller's info is misplaced and a bit weird. We are perfectly capable of determining for ourselves if someone acted honorably or dishonorably in a deal.

[The Monkey]

Oh, and what Al said.

[justin]

i'm pretty sure I know who the original owner of this amp is. and the original price was $1k.

[RockCity]

Hi Voltron, there really was no secrecy. In fact, I stated on page one that this amp was from the 02/20/11 meet. It's easy to figure out who brought the amp to that meet.

On the second page, I didn't give out the name at first because you and several others began criticizing the components in the amp. Subsequently, Monkey asked for the owner's name. I felt people decided that the problems had a relationship to the owner as opposed to the build quality. Also, I felt that the mixed components was a separate issue to the humming; people were just criticizing anything wrong they can find in the amp. If you want the truth, I think no one fucked around in the amp. It was Justin's work. I am not a DIY but a basic detective can tell that the amp had not been opened and that these features were workarounds in a preliminary design. I already explained this as simple as I could in my posts.

Justin, I will be rescinding my request since the your suggestion is more extensive than I imagined. When I looked at the stock images of the production KGSS it not appear visibly different therefore I thought a maintenance was possible. Thank you for answering my questions.

[justin]

i thought you said the amp had been opened because the cover was put on upside down? not a mistake i would have made, i had been using that brand of enclosures for a while

while it may not be too difficult to figure out what is causing the hum and replace a part, i wouldn't want to send it back to you unless everything was up to current standards.

[RockCity]

I am stating that the cover was upside down for a long time. The age and conditioning match the rest of the unit. What this means is that had the amp been opened, it would be have been opened when it was in new condition and a long time ago. The correct side of the panel is in remarkable shape. Furthermore, there is not a single fingerprint or on the correct side meaning there is a chance that it was never installed the right side up in the first place. If it were passed around and opened as frequently as Voltron suggests, someone would have noticed the mistake and also touched both sides of the cover.

[justin]

I am stating that the cover was upside down for a long time. The age and conditioning match the rest of the unit. What this means is that had the amp been opened, it would be have been opened when it was in new condition and a long time ago. The correct side of the panel is in remarkable shape. Furthermore, there is not a single fingerprint or on the correct side meaning there is a chance that it was never installed the right side up in the first place. If it were passed around and opened as frequently as Voltron suggests, someone would have noticed the mistake and also touched both sides of the cover.

the bottom side always has scratches on it, even on a new enclosure.

[RockCity]

Correct, none of the products I received whether it was from Singlepower, Woo, or Eddie Current were free from cosmetic defects. There were always signs of workmenship and assembly. However, the condition on one side is conclusively better than the other. All audio components display their age from basic touching to racking or user abuse. Meaning most if not all of its age was shown on the wrong side. Furthermore, the metal has a curve from heat expansion to suggest this was the configuration for a while.

[swt61]

Nobody else has mentioned this, and maybe nobody else would care about it, but IMO having one of, if not 'the' first KGSS Justin built would be worth something in it's own right. I'd consider that a collectors piece, and would want to retain the early workmanship. Of coarse if you only have funds for one amp that might be different, in such a case I'd ask the seller for a refund and buy a new or newer KGSS. It's a simpler solution, and I doubt that Justin needs the headache.

The first headphone stand I ever built (Duggeh's) is not the prettiest, or my best work, but it still has a significant meaning for me.

[Voltron]

Fingerprints? Age and conditioning match? Basic detective? Look, Rockford Files, your comments have proven exactly what I was saying. You have been convinced since the beginning that Justin is "to blame": "I think no one fucked around in the amp. It was Justin's work." This belief is irrelevant, but also inconsistent with your detective findings. Although you are wrong that I suggested the amp was opened multiple times, it is clear that somebody opened it after Justin shipped it because there is zero chance he would have shipped it upside down and backwards. Zero. That means it was opened at least once and nobody knows what was done, what might have failed in 8 years, etc. None of this shit matters to anybody but you.

If I were to attribute an ulterior motive to your actions here, I would suggest that you suspected this amp was early work by Justin that didn't look up to his current standard and that if you posted pics and insinuations then he might be embarrassed into updating it for you for free. I'm not saying that was your goal, but given your belief that this is Justin's work, all you had to do was send him a PM or email with the pics and ask him if those conditions were in the original amp when he shipped it 8 fricking years ago. That would be a straightforward way to get answers and perhaps find out if he were interested in checking it out and/or updating it for you.

Instead, you went through all of this hoopla and drew a lot of attention to your alleged plight. You're not going to get any traction here, or any free work, or anything else. Just decide what you're going to do and do it.