[andrzejpw]

nice amp, congrats? Is that a pactec case?

 

[Kal525]

thanks for all the comments guys.

. Quote:

Off-board wiring those panasonic pots is a bitch, no?

You have no idea, wiring the pot the way you see there was probably the hardest thing to do, especially since i was working on it by myself. I'd have to hold the wires onto those tiny leads and just as it got hot enough to melt the solder my fingers would burn and i'd move the damn thing so that it was soldered on top of a different wire, such a pain in the ass, but i finally got it working, although one of the leads did snap off.........next "investment", blue velvet pot

Quote:

Oh, what size is your amp? It's hard to tell in pics.

The case you see is a pactec LH57. I actually got the idea for it from you, andrzejpw. I liked the way yours came out. It's kind of big, but that's not a big deal since it's not going anywhere. I'll take a picture of it with some reference so you can compare and see how big it is.

Quote:

Good looking amp. Some big caps in there.

Thanks, i don't think they're actually that big though, they're 470 uF 25 v caps and they fit perfectly in the pcb, not a tight fit at all, not like some of those offboard caps i've seen pictures of. I wonder what difference getting bigger caps would have made......

Quote:

From Digikey- search for KILO

Part no. ML-75-1-6MM

Quote:

and the locking 1/4 would be nice

part no. 568-NJ3FP6C



I'll post some more pics tomorrow, normal size for those bandwidth impaired

 

[Maxvla]

Quote:

Originally posted by Kal525 Part no. ML-75-1-6MM part no. 568-NJ3FP6C

thanks

 

[Voodoochile]

quote:
--------------------------------------------------------------------------------
You have no idea, wiring the pot the way you see there was probably the hardest thing to do
--------------------------------------------------------------------------------

Heh... actually, I do have an idea

, hence my remark. I have mounted that same pot in most of the cmoys I have built (serpac cases). The first one was a real drag... the second went better, and only easier since then!

 

[Kal525]

ok, after the past few days of trying out my new project, i can't figure out why i can't tell the difference between my sound card headphone jack and the amp and it's really starting to piss me off. Maybe my ears are just untrained or something, but i thought that i would hear a major difference, but i'm just not hearing it. Do you think it's because of my source or what i'm listening to, i just can't figure it out. The amp is hooked up to the back of a Game Theatre XP via RCA jack outputs, so i'm not being stupid and amplifing the headphone signal. Is it possible to have built something wrong so that i just get sound but not the best sound, something just doesn't add up. I mean the amp does sound good, but when i plug into the headphone jack on the sound card and listen to the same song, i can't tell a single difference....maybe a miniscule difference on some songs. Is there something i'm doing wrong??

 

[Maxvla]

i bet its the source.

 

[was ist los?]

are there 1/8" locking jacks?

 

[antness]

I used to have a Game Theater XP, and it's headphone output isn't too bad. I never was able to get the box completely open without destroying it to examine the amplifier circuit.

However, if you are listening to MP3s, that may be the reason you can't tell a difference. Also, the source is a major factor, a Game Theater XP is a pretty poor source. Try any dedicated CD player and you'll be blown away. You can probably hook up a dedicated CD player to the Game Theater XP to compare the headphone outputs that way.

 

[Voodoochile]

I also have the GTXP, and although it's pretty nice in the realm of PC sound, it's still PC sound. MP3s sound really nice through my monsoon comp speakers, but I hooked the laptop up to my Integra amp one day to listen to some of the rips, and WOW, it sucks the big one. I increased the bitrate quite a bit as an experiment, but there is still quite a difference. It is, after all, a lossy compression scheme, and it's not too hard to hear it.

I have seen threads where people want to hook up their Klipsch PC speakers in the livingroom to make a "bitchin' stereo system". They may sound nice on the computer, but in the livingroom, there are a LOT of other speakers that will sound much, much better.

Plug a standalone Cd player or DVD player into the META and give it a listen, as compared to hearing it play through your headphone jack. I'd be surprised if the difference is not quite pronounced, unless you happen to own mostly Mark Levinson stuff or some other high-end hardware.

Another thing that was a real learning experience for me was to construct a healthy but simple cmoy for the purposes of listening to different op-amps, as Tangent describes in his website. Mine has 1uF film and foil polypro coupling caps (so I can use it with any source, regrdless), and the PS has the divider resistors replaced with a railsplitter and a pair of BUF634s. There is the extra cap upstream of the BUFs per BDX's supply, and the last pair on the PSU box are non-polar. The boards for both the PSU and the amp are mounted on top of the enclosures, with the wiring inside running to the pot and jacks. No buffering or second op-amp output stages- all you hear is the op-amp. Being able to listen/kill power/swap chips/repower/listen makes even the suble difference between chips noticible, firsthand. And no, I don't even own HD600s. I have a pair of 497s, a pair of 570s, and a pair of SR80s.

An amp can help with a PC setup (especially fi you use high-impedance cans, but you have to ask why), but the benefits are not as likely to be so pronounced, IMHO. Frequently, the added resoulution only serves to magnify the shortcomings of the source.

 

[Kal525]

thanks a lot for the input guys, i'm gonna try a few of the things you mentioned and post back here with the results. I think you are both probably right in saying that it's my poor source and the media i am listening to. Since you have both owned GTXPs i now know for sure this is the case. It's such a shame though, the GTXP sounds great with my......klipsch promedia 5.1 setup

I guess i'm slowly realizing the cost of transitioning into hifi, $400 speakers just won't cut it, and neither will a crappy source. I guess my collection of mp3s is a waste then huh? Is there any sound card you know of that lets out a good signal? I mean it must be possible to listen to cd quality mp3s from a pc. The GTXP does definitely have it's problems though, apart from the fact that i can't differentiate the sound. There is a very annoying hiss at high levels of vlolume, which after doing some research i have learned that i would basically have to live with this hiss as there is no cure.

I have tried hooking the amp into a receiver downstairs, but did not try comparing it to the headphone jack. I am guessing the headphone jack will sound really good as well, as it is housed inside the superwoofer. I tried it in this jack before i had built the amp and it sounded pretty damn good, far from underpowered. I will definitely play around with that though, and i will try to hook up a source to the GTXP and listen through a DVD player to see what the difference is.

What do you guys use as a source? Is there ANY way to listen to mp3s on my hd with a good source?

Thanks again for the input.

 

[Voodoochile]

I'm certainly not the MP3 king, but I think it's partially due to the lossy encoding.

Another thing, the computer is a hostile environment for a soundcard. Even though there is an external breakout box, the main card is still inside the PC, the box is principally I/O stuff. Don't feel too bad about your Klipsch setup- it's pretty awesome for computer use, no doubt!

Perhaps someone here has used one of the network-attached playback nodes that fit in with your stereo equipment, leaving the computer in another part of the house. I have seen one somewhere. It just streams the data to the small box, which then connects to your amp (or headamp). That would help isolate any interference, but I think the quality issues are more likely with encoding. (I'm probably wrong on this, but someone who can make a better rip can step forward and tell how).

I really like the idea of the hi-fi node, but don't have the dinero right now. I have a server running in the basement workshop with a pile of MP3s as it is, which I map out to the computers upstairs.

In your example the HD in combination with the GTXP IS the source. I have a Kenwood PCDP, and a regular Luxman CDP for sources.

 

[Kal525]

ok, i just tried listening to different stuff through a dvd player and my amp and then attatched the dvd player to the GTXP and listened to the same stuff through the GTXPs headphone jack. The result again has me pissed off that i can't hear a difference. Either the GTXP has a really good headphone jack or my ears are just too untrained. I don't understand what i'm listening for. I've tried to pick a specific instrument to see if it's improved, and i've also tried to just listen to the "big picture." I still can't tell any difference though. I'm gonna go out right now and buy a mini to rca cable so that i can at least comfort myself that the amp makes an improvement with portable audio..........even though my amp isn't portable, damn it.

 

[Kal525]

do you think it could be my interconnects? I'm using plain old generic ICs. I wonder if they could be the weakest link in the chain. I really hope that it's something fixable, cause i'm really starting to think that i must have done something wrong in the construction........but then i should be getting no sound right?

I am now set back a few notches. I need to figure out how to get the amp sounding like it's worth $200 and i need to find a usable source/IC. I'll take any suggestions/comments.

oh, and Happy New Year everyone, let it be a safe and fun one......i'll be in Avaland with Ron Jeremy

 

[andrzejpw]

Just try listening to your META setup for a while. Just listen to it for a week or two. Then let us know.

To be honest, I used to have the same problem. I just couldn't tell! These days, I just can't help but think things such as "Ugh, no bass, and lack of treble extension."

 

[Kal525]

I think you're right. I'm gonna give it a while to break in. My headphones aren't even broken in yet so it could be a lot of things that are affecting the sound quality. I think the ICs have something to do with it though, along with my source. My next problem lies in finding a good source and RCA interconnects to use the amp with as my previous plan of using it with my sound card seems doomed to failure. Anyone have any ideas, wheather it be for a cheap standalone cd player, a sound card with a good source, or good interconnects ( i think i'm returning the monster ICs i purchased from Best Buy after doing some searches on this forum). Hope everyone had a good New Year.