Torpedo

I never thought the change in sound on the Rudi had anything to do with phase. IMO it's for additional load. Not sure if the RPX-100 is capacitor coupled though. I think both outputs use the same amplifier section. Rgrds

LOL Dr Mengele's prescription?

Thanks Nate. I don't have detailed pics other than the ones Justin posted at the beginning of the thread. Let's see if Justin shows up later and wants to clarify. Otherwise I can open my unit and try to get some decent pics, or just see for myself if sound quality suffers any changes by plugging a second pair of phones into the other output. On the Rudi this has a very clear impact in the sound. Rgrds

It's not about preserving absolute polarity, which AFAIK is preserved in my system, since listening with phones I can't really say if it's "correct" or not, even less considering many recordings have it completely messed up. My interest comes from knowing if using both SE outputs at the same time I'm loading the same amplification rails, or each phone would be using a rail for its own. As I see it, having each SE output using different phases of the balanced configuration, would be the same as having two separate SE amps, one with opposite signal polarity than the other one. Rgrds

I've tried to edit the post to add a question for Justin, but looks like it's not possible, or I'm too idiot to see how to do it Anyway... Since the amp is balanced and has two single ended HP outs, I wonder if both SE outs come from the same rail of each channel, which I suppose is the "hot" one, or one SE out is using the amplification for the hot side of the balanced circuit, while the other SE out uses the cold one. If this were the case, what SE out is using the hot (preserved polarity) part of the circuit and which one is the reversed? I could investigate this myself quite easily had I an oscilloscope, but I don't have it, nor a reliable meter to check polarity either. My guess is that both SE outs use the same perserved polarity circuit, othewise when using the SE input only one of the SE outs would be working, unless some phase inversion circuit gets activated when switching to SE operation in the back, so both balanced rails get signal. Rgrds PS. Looks like the "edit" button is active right after the message is posted, but I swear it wasn't (and still isn't) there when I tried to edit my previous message.

Thanks mate! The amp arrived about two hours ago. I've plugged it into the system replacing the Rudi, fed it with a balanced signal from my DAC and for first listening I've chosen the L3000. Music: Kenny Barron - Live at Bradley's. Initial impressions are very good. I was expecting kind of more "trendy" sound full of enhanced detail, transparency "uber alles", some agressive attacks, shortened decays and those SS harmonics which aren't very full and natural... the kind of attributes that lead some people to say that some piece of kit is not "musical". Nothing of all that has happened, if anything, attacks are in the punchy side of things, but probably just when the playing is that way. Of course I have to listen to really "audio evaluation suitable" music, and trying the rest of the cans, we'll see how it does with more resolving phones. As for now I'm quite pleased with the purchase so far, this amp shows some potential and intersting features. Thanks to all who have contributed to this purchase Not sure if my "final" amp yet, though an interesting one to own and evaluate. Rgrds

I see...

^ Does she blow some instrument properly or is she just cutie?

Well, the seller took his time to sort out everything, but we've finally closed a deal and I've just ordered payment for that Gilmore Reference Balanced. Hopefully I'll have it here by next Wednesday or Thursday. We'll see how I like it

I own a modified Bidat, a friend of mine owns another one which has external PS transformer, and I had the chance to listen to the modified Melior in my system. They're different DACs, I mean all three, but the Bidats are different animals than the Melior. For some time Bidats were produced using a switching PS too, but they stopped that and got back to the normal PS. It's very possible that Deepak liked the Melior, it's really engaging. It has that kind of "bitstream" sound that also some old Marantz players and Discmans have, but with a bit more of resolution. Regarding the top loaders, I wouldn't dismiss the CEC transports either. The old Sony CDP-X7xx-ES series were very good ones, I still keep a 707 "just in case" Rgrds

Do you mean a Museatex Melior? Nice sounding DACs. Maybe Meitner was more into good sound than into making money those days

LOL BTW those Neutriks look about the same. Any internal difference? Rgrds

Have you tried to get into the chatroom? I can't access for the lack of the plugin. I've been using it today and still has an erratic behaviour. Sometimes it displays pages very fast, like no other, and other times... well feels like frozen. I like some of the features like the spell checker -but being this a Spanish version marks everything wrong while wrting in English- and the ease for copying pics' links. I suppose that when they fix it, add all the plugins and some final version is released, it can be one of the best browsers.

^ My comment was for the passive EQ device, not for their speakers. A single driver has physical limitations which prevent it to deliver low frequencies. Increasing them by EQing is IMHO a no-no situation which most likely will cause the driver to severely distort and screw up the rest of its performance. Rgrds

I wouldn't be much concerned about the frequency issue unless you were to drive a turntable. Most modern electronic devices can work perfectly at 60 or 50Hz without a single problem. Otherwise the thousands of americans travelling to Europe would have fried a lot of laptops and many other electronics, and europeans travelling to USA had done the very same Make sure that Korea has 220V and not 230 or 240, that could cause a higher voltage delivered to the device when a surge happens. In fact getting there a decent surge protector wouldn't be a bad idea. Regarding trannies... not sure what to advice, it largely depends on how many devices he's planning to take and the power consumption they'd add altogether. Rgrds

That sounds to me like but considering I haven't tried it, who knows... And yes, I think Boomana has the Cain&Cain listed on her system.

The Zu Druids along with some Audio Note models are quite sensitive for not being horn designs, but any of them would be way more expensive than your budget even used. I haven't any direct reliable reference of the sound of these but for a bit more of your budget they could be an interesting "experiment". Rgrds

JJ tubes were produced upon the factory that Tesla tubes once were made, and had a very good quality, for built and for sound quality, but as long as their sales have been increasing, it's said they moved to a bigger facility. Maybe they outsourced production of some parts to China, who knows. The fact is that their quality has been going down with time. In the last two years I haven't had a E34L quartet that lasted for more than 1200 hours. Most of them fail for one of the pins losing connection to the inner wires, and can't be fixed by filling the pin with soldering. Once one of the tubes fails, you need to change all four in my amp for its fixed bias design. Maybe using other brand tubes for this experiment yields different results. In my experience, cryoing JJ E34L is not a good idea. The ones that the manufacturer sent for cryoing were some from an old batch, probably made in the late 90s or early 2000, and were compared to tubes of that same batch. It hadn't been smart comparing "better made" tubes cryoed to some of recent production ones, which we knew had lower quality.

The cryo treatment was performed by a company that does that for Hovland and other electronic parts manufacturers using cryo treated components. I don't know if they know their bussiness, but I'm prone to believe they do.

Yep, the high sensitivity and affordable speakers market is full of compromises. Even of the big very expensive ones is. My advice is that you tried to listen to a few ones with your amps and took the ones you found more satisfying for your taste and priorities. Rgrds

We had already done that. The tubes after cryoing (the power tubes) not only sounded different, but also measured different after treatment. Measurements were taken -the manufacturer told us and I have to believe him- right after the tubes got to him, then he burnt them for about 24 hours and repeated measurements. I don't recall the exact figure, the manufacturer told us that they had lost some power delivery which hadn't recovered after that burn-in. In our experiment the tubes were used already burnt-in by the manufacturer. This was less significative on the small signal tubes (6922) and while the sound was different, it really wasn't "that" different. Justin, I won't get into the statistics discussion about how many trials give significance to a test, nor how to make a proper DBT, please consider that I'm a MD involved in clinical research. We made this more than two years ago just to help the manufacturer to decide if it was worth cryoing the tubes he included with his amps. We didn't pretend to make a scientifically 100% valid test, nor I'm claiming this is even close to "true science". IMHO the test is good enough, and as far as I was involved in the listening, I'm pretty sure the tubes sounded different, especially the cryoed power ones. Rgrds

Oh yeah, Happy Bday mate!!!

No, not easy at all, specially in the first assessments when the cryoed and un-cryoed very hot EL34 had to be swapped. The guy used the gloves to take hot trays off the oven. We were afraid of the tubes being damaged for hot swapping, but they stood well.

This was a long "experiment" and we worked on 4 different scenarios: - Cryoed input 6922 using non-cryoed power EL34 - Cryoed input and cryoed power tubes. - Normal input tube and cryoed EL-34 The reference for the DBT was a set of normal tubes and we carried it only to compare the cryoed 6922 + normal EL34, because it was this combination the only one that offered small and not so clear differences. All the other combinations involving cryoed power tubes sounded so different for everyone attending the test, that we decided it wasn't necessary spending much time on a DBT. We had two sets of cryoed tubes and two sets of normal tubes, but only needed one set of each, all measured by the amp designer-manufacturer and matching within 99.5% before the cryo treatment. We had two amps, one used just to keep the tubes warm driving a resistive load and the other for the listening. The trickiest part was swapping tubes while they were hot Obviously the test wasn't strictly double blind since the pal swapping tubes knew which ones he was plugging, and it wasn't immediate A/B, but none of the listeners knew if the cryoed or un-cryoed 6922 was on until the end. We were 4 listeners, plus the manufacturer who was swapping the tubes. I'm not sure now how many trials we made, something between 6 and 8. Two of us spotted the tubes used right in all of them. I've made other blind tests using tubes, but none as thorough as this one and none invoving cryoed tubes. Rgrds

We used tubes from the same manufacturer, which were measured by the amp's manufacturer before being sent for cryoing, and also after treatment. The power tubes were matched as quartets. They were JJ 6922 and JJ E34L. For sound and measurements, it's as though cryoing had aged the tubes. The DBT was carried quite seriously, the manufacturer of the amp was really into knowing if the cryo treatment was worth the expense and the hassle. Using the same procedure, but without being able to DBT, is how the cryoed and uncryoed caps were used. Two identical amps measuring the same, using the very same tubes, one with cryoed caps and the other with normal ones. We made it twice, one in my place and the other at one of my friend's. Despite the non-DBT I think the results were consistent.