-
Posts
14,495 -
Joined
-
Last visited
-
Days Won
23
Content Type
Profiles
Forums
Events
Everything posted by spritzer
-
Watching the show it took me a while to figure out what that song was. Very good cover...
-
Yes, same math they used in 2006 for the housing market in the US. Moar+moar=MOAR!!!!! Works great... That graph makes me wonder though, does Cavalli not understand it or does he think his potential customers are braindead idiots? I'll start work on ripping this POS apart tomorrow and a new CCS using 2SA1968 it is. New Fairchild output devices as they are in current production and lower the output capacitance more than 10 fold. See if I don't have some J74's of the right IDSS too. Are the LSJ74's shipping yet?
-
I'm a glutton for punishment, that's why I'm modifying it. It was also about time somebody spoke up about this amp once and for all as it isn't normal that something is sold after just one days ownership, by three people. One of the amps out there is fast approaching the tenth owner in a year. Before I begin, here is a picture of the amp in full D800 glory: http://gilmore.chem.northwestern.edu/ll-1.jpg Easy see here that this is just an Exstata with a CCS. Same basic layout except the output devices have their own sinks rotated 90° (there were two on each sink in the Exstata) and the CCS is on those small sinks towards the front. The resistors between the main sinks are now the CCS. Another thing of interest is the bias supply. Just below the transformers in that pic, next to the white caps you can see two CMF55 4.7M resistors. Those are the ballast resistors for the bias and an important safety feature. The CMF55 is how ever rated for max 250V but here it is sitting at 600V. Should be fine when the bias is an open circuit but if it shorts to ground then those resistors are useless. Also notice the small jumper next to them, that selects between high and low bias. Not the best idea to run these at high voltage... What I have to do is to add loopouts to the back of the amp, do something about those Stax sockets and replace almost all of the transistors used in the amp with new BJT's to decrease the distortion by 15-20dB - ditto the output capacitance down to ca. 20pf. I'm also thinking about scrapping the main CCS as it is just fucked. My options would be to go with a BHSE style design or what Stax are already using in the SRM-323S. The latter should be more stable in this circuit and just needs one 2.5" heatsink per phase.
-
I've been the proud owner of a Cavalli Audio Liquid Lightning for over a month now. Now as most will know, this hasn't been exactly a dream of mine but the owner practically begged me to take it and the price was low enough to waste money on it. The normal market price on the Mk1 model has dropped well below half of retail (2400$) at this point and this one was even cheaper. What finally made me buy it is the very unhealthy discussion about this piece and the clear attempts of the manufacturer to kill any negative discussion about it. My views will be questioned because of my history with Cavalli but that's exactly what should be done to any impression that is read. Nothing should be taken as gospel but I've put my money where my mouth is and that's not something you can say about the people who rave about the LL. The main goal of this thread though will be to document just how badly built and designed this amp is but also to document ways of improving is and indeed, making it safe for the user. The circuit has been fully drawn up and analyzed and it will be posted in full later on. Any issues of copyright are blown aside as this is very similar to the Exstata which in it self was a Stax design lifted off the web. Cavalli has admitted to that in the past and the "improvements" make it even more similar to the SRM-323/727. We'll get to that later though when I start the ordeal of making something useful out of this box. Perhaps we should start with some impressions of the sound. First impressions were just how small it is and very light. It's about double the size of the SRM-727/007t but doesn't weigh all that much more. The casework is flimsy but well made. Some plainly odd bits such as the volume knob is painted, not powder coated as one would expect and there is no primer used. Very odd... The switch on the front is neat but the circuit driving it could use a lot of work. As for the sound, well the output capacitance of this amp is about 300pf so it sounds very odd. It's utterly unusable with the SR-003 as they are just 44pf with the cable. Same with the SR-007 and SR-Omega, way, way too much bass, no life at all and the treble is just gone. The midrange which makes these so special has no depth, no height so voices just sit flat on the front of your face. Let's break this down a bit: The bass is by far the worst part about this amp. There is no sub bass output and the rest is both anemic and overblown at the same time. The bass has no power, no heft until it hits a certain frequency range and then it turns into a overblown mess that consumes everything. This is worthy of cheap closed dynamics and is very annoying. The SR-007 when driven well rivals any transducer when it comes to bass impact but here it is just a weak muddling mess. The midrange doesn't have any presence or bite to it, it just sits there. The soundstage has no depth and is pretty much stuck directly in front of the face. Remember those bell graphs... that's how it sounds. Some output low down on each side but almost everything in the center. The HE90/Stax hybrid I have rivals even the Sigma's when it comes to casting a vast soundstage but here it is just dead. The lovely out of head experience of the SR-Omega... completely gone. Voices are separate and not really joined in with the rest of the stage, almost like a bubble directly in front of the eyes. Truly weird and it's there no matter the recording. The top end is highly rolled off, there are no shimmering cymbals here or guitars piercing as they are driven into overload. Nope, just lifeless and inoffensive. I can see people liking the SR-009 with this but it's like taking a sledgehammer to the sound. Instead of gently molding the top end it's just cut off entirely. Now this is the Liquid Lightning Mk1 I have here so how different is it to the Mk2? Well until I posted my findings it was supposed to be identical on the inside, all the same parts used and just some slight tweaking plus the new case. Now suddenly it is massively different and a gigantic improvement. Nothing backs this up, no pictures, no clearly defined part changes and only the testimony of people to who I wouldn't take at their word. Until something comes along that actually backs up these stories of major improvements then I have to assume that they are exactly the same. Same output devices which have a combined output capacitance of 270pf per transducer and the same fucked CCS that kills the top end and fucks up the phasing on the low end. Finally the first steps in improving this pile of fail. I naturally needed to change it to 230V so I was greeted by this: That is not a very professional job to be honest. Two wires are the primary windings of the small standby transformer and the two green wires are the pass through to the large HV transformer. Here is how I did it. Fun fact, there is actually no locknut on that grounding post. There are two lock washers but they are both right next to the eyelet, there is none on the nut which secures the whole assembly. You can see where this is going, fucking amateur hour... To cap this off I decided the blue knob had to go. This is what I had "in stock": Much better and since that is a Headamp knob I hoped that the amp would sound a bit better. It didn't...
-
Well yes but one goes hand in hand with the other. They are only there under fault situations though.
-
It was on Y!JP but you have to know where to look. No way that the transformer would survive driving the ECC99's. It's run on the edge as it is. You can put the output resistors directly on the socket. They are simply there to limit the output voltage should any of them short to ground.
-
The schematics will be posted and some measurements but don't expect some fancy AP graphs like the one on the Cavalli site which break the laws of physics. One thing off the top of my head, the PSU has 20 times the noise of the KGSSHV unit and drifts all over the place. That's the good part of the amp though... I was changing the amp to 230V yesterday and decided that horrible knob had to go. That one I got from Justin... I do think that this issue deserves a new thread so I'll probably start one later. I'll also include new impressions based on some time with the Omegas, SR-X Mk3 Pro and the SR-003. The last one was not a pleasant experience. The output capacitance of the amp is roughly 7 times that of the headphones. Edit: I've also found one major safety issue with the LL. Complete fuckup and goes to show how clueless these idiots are. Think ballast resistors rated at max 250V running at 600V. Under normal conditions this isn't a problem due to the open circuit but if the bias shorts to anywhere this is your only safety mechanism. Also, no output resistors on the amplifier. Not a good idea... I never bothered to draw it up but this is what it looks like: http://www.op316.com/tubes/schema/image/stax-srm1.jpg Just fill in the values. Stax never did packages back in the day. Some distributor may have bundled something together but the first official combo was the SR-5NB/SRD-7Mk2 in a cheap plastic container. 1N4007 works just fine, nothing eating up 1A of current in there. I would double up for a full bridge but that is optional. Those are the output caps btw. and I always replace them. In vintage Stax news I bought that SRA-7S in Japan. A lot work to repair it but a perfect match for my SR-1's.
-
I don't think I could sell this one to be honest. It's just too bloody bad...
-
T1 is just mehhhh. Not good... not bad... it just sits there but not in a good way. The 727 is not doing the 009 any favors though. Pretty much the same as the steaming pile of fail on the top of the rack here... So when I'll make it useable, should I change the color of the power button and the knob? I'm thinking silver with amber led's... Frank Zappa - Dinah-Moe-Humm is utterly unlistenable on bass light transducers. Nothing but out of control bass...
-
That's a lovely box you have there. Good point. We need Kevin to start work on some stronger, non conductive screws...
-
Haven't touched it after the initial mod. Not sure if anything can be done with it to be honest. Steaming pile of shit that one... I anybody knows about a good BJT that is 800V or more in a DPAK package I'm all ears. Low output capacitance is a must have.
-
Repair and restoration of my STAX SRA-12S
spritzer replied to Quad's topic in Headphone Amplification
Ohh so true. Give me BJT's or give me death!!! -
Ok, I think I've found a good set of earpads for these and they were dirt cheap, the Brainwavz HM5 pads. They were a bit too small so some force is needed to attach them but the material is quite nice and they are very comfy. The sound seems to strike the correct balance so lively yet about as neutral as they can be. The really good bit... they cost 17$ shipped for the pair.
-
Repair and restoration of my STAX SRA-12S
spritzer replied to Quad's topic in Headphone Amplification
Well the schematic being wrong doesn't surprise anybody, this is Stax after all. They always leave errors in the schematics. This amp was also in production for a long time and during that time semiconductors came of age so to speak. Ohhh and you can still buy the design today.... it's called the KingSound M-10 and is fucking awful. -
Happy Birthday!!!
-
Most excellent as I just got way too many of these boards.
-
Yup, that and the - voltages all over the datasheet means PNP.
-
This shit is like tuberolling, people want to do that on the fly as well.
-
No, scrap that. I was working from the second oldest version of the PCB and it didn't have these changes. Now I see what Kevin did... All the parts labeled A should not be used with IXYS parts.
-
Not sure why that LED in the corner is labeled A... shouldn't be. Uninsulated diodes on the HV are not recommended. I'd remove them and fit the correct ones, the ones printed on the PCB. Ohh and one more thing, never... ever try to change the feedback with the amp running.
-
Time for an update. The well worn SR-007 pads were an upgrade but made the bass too anemic. Distance from the driver and the chamber size being the most likely culprits. It's more linear but just... too bland. Today I got the W3000ANV pads and they are lack a bit in comfort compared to the 007 pads but I can live with it. Mmmm leather... The sound is better with them too, bass has a bit more bloom and the top end is smooth. Still these have serious issues and that echo/phase issue hasn't been resolved. I'll probably have to take the drivers apart which is not something I look forward to.
-
Well my MSB is not DSD upgradeable so this would work for me. That said if I'd care about DSD one bit...
-
They are optional so feel free to leave them out. The smaller layout is completely the same as the bigger boards.... just smaller.
-
Yeah,,, missing 20K units would make no sense as it sets the output voltage. 3900pf should be 1000V or more.
-
Could be worth a shot to ask these guys: http://www.garrard501.com/