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Graham Slee 
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Retired Joined: 11 Jan 2008 Location: South Yorkshire Status: Offline Points: 16298 |
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 Posted: 26 Jul 2022 at 2:18pm |
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John C just read a review of the Era Gold V by a competitor on ASR. When somebody needs to libel another to sell anything, they've got a serious problem. So they think it's an AD817... Anyway, thanks to Shane for pointing out this drivel. Science my arse!
Edited by Graham Slee - 29 Jul 2022 at 10:20pm |
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Graham Slee
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Retired Joined: 11 Jan 2008 Location: South Yorkshire Status: Offline Points: 16298 |
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Posted: 26 Jul 2022 at 4:16pm |
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Anyway, I got to thinking that, well we're the smallest of the well-known's, and that's because right from the start (1998), all the rich guys and the guys in America and the big companies and the hi-fi press and most dealers, did nothing but put us down - even without sampling our products - and that was very true on Head-Fi. (all these can try to take us to court but we retain proof!) The Solo headphone amplifier sounded awful according to a Head-Fi poster, who later admitted he'd never heard one and he wanted to protect his favourite brand from any competition - that's true! The competing brand is wealthy by comparison, and I cannot believe for one moment that Michaelson would condone such subterfuge, so it looks like there are some people who have a serious problem. However, such types have followers who like to echo what their heroes say. As such, we never had any "fame" with the headphone amplifiers until we started getting five star reviews from some in the press. I must also add that technically it was good enough for the US military to buy hundreds for use out in the middle east - or is that an official secret? I never signed the official secret's act so I believe I'm free to share this. As for the Era Gold V that sells in the hundreds (big deal), I can tell you a history about its put-downs too. There are a lot of amplifiers purporting to be high end that are made for older listeners who's upper frequency hearing is shot. Some old reviewers like them too, and due to the weight they carry, younger users are convinced that the screechy bright sound is normal for hi-fi. It isn't. So when I designed the Era Gold V (on my usual shoelace budget) I designed it to have a flat extended frequency response, and when the brightness of such amplifiers is added... well, it didn't bode well, did it? So, I remember the gushing in HiFi Choice for "Timmy's" (RIP) phono stage - and I still have the copy here, so this isn't libel, and the Era Gold V was slammed and given 2 stars. They were kind enough to send it back, so I then sent it to Mr Fremer, who went ecstatic about it. So, by now you might get some kind of impression of envy, and perhaps greed, entering the so-called unbiased reporting? Now, around exactly the same time as the rave Fremer review, the Canadian distributor insisted the PSU1 got CSA or Canadian UL approval, and he'd get my US distributor worried about it to blackmail me into doing it (yes Kurt, I remember the phone call - I made notes as evidence). That put the kybosh on sales and by the time the approval was granted, the impetus had evaporated. Then in 2005 we learned that in 2006 all our non-RoHS containing products would be banned from sale - but the Chinese would be given 2 years grace to comply. Stinks? So I then had to redesign just about everything, because my ears told me that RoHS compliant components sounded sh*t by comparison. Funny how nobody else noticed... And so, not benefitting in any way from anything we struggled on and only cut costs where it didn't matter, so we made the Era Gold V board do other jobs too, and by simply changing the circuitry the board was fitted to other products. That required links and cuts and the manufacturing drawings were produced so we knew what to do. Also, we don't use solder mask (except on the Accession) because we don't flow solder. As for the holes that we supposedly drill, the boards are manufactured by ABL Circuits and they use one of three CNC high speed PCB drilling machines. The reviewer might be referring to the holes that were used as track cuts, but these were drilled using an upstroke optical machine using the same Excellon turbo drills used on CNC's. As for my experience of printed circuit boards, I used to manufacture them, yes, and design them, for Siemens, Cable and Wireless etc. So, I must assume the reviewer is yet another nasty piece of work who wants to put me down. So excuse me for not having any respect for him/her/it.
Edited by Graham Slee - 26 Jul 2022 at 4:17pm |
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Ash
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Joined: 18 Mar 2013 Location: Dorset Status: Offline Points: 4334 |
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Posted: 26 Jul 2022 at 7:37pm |
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That is the biggest load of bollocks I've ever read. It's so false that I consider it slander. Perhaps I need to properly review your Bitzie/Solo/Majestic/Proprius on head-fi with all my photos of HD540II, HD800, K1000, MySphere 3.1 and Mark Audio drivers, to shut those dishonest pretentious clowns up. I tend to spend my time enjoying listening to music rather than embarking on the time-consuming process of writing lengthy reviews but if you would like me to challenge false information on your behalf with my name and photo, lemme at them. I will show no mercy to anyone who puts your products down without any kind of justification. When I do eventually double DAC-amp, I will be able to take some more photos and say "Look at my Slee electronics; it's all so crap, I bought two of everything!!"
 Edited by Ash - 26 Jul 2022 at 7:56pm |
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We do not see things as they are. We see things as we are.
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Fatmangolf
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Joined: 23 Dec 2009 Location: Middlesbrough Status: Offline Points: 9001 |
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Posted: 26 Jul 2022 at 8:26pm |
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Thanks Graham. We need someone to demystify the nonsense about op amps, showing how to develop the circuitry and fine tune the sound for music not just s/n stats.
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Jon
Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC. |
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Graham Slee
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Retired Joined: 11 Jan 2008 Location: South Yorkshire Status: Offline Points: 16298 |
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Posted: 26 Jul 2022 at 9:37pm |
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Since then, Head-Fi have not caused anymore trouble. It's the new kid on the block's forum and his members...
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That none should be able to buy or sell without a smartphone and the knowledge in how to use apps
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Graham Slee
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Retired Joined: 11 Jan 2008 Location: South Yorkshire Status: Offline Points: 16298 |
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Posted: 26 Jul 2022 at 9:57pm |
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A lot of it becomes intuitive after a while, like the example of the "imaginary resistor". It appears in parallel with a negative feedback RIAA filter, and so alters the calculated response. The simulator blows the gaff. After all, it's a master mathematician! Then again, you make what the simulator says and then measure it in real life and it's still someway out, and that's because of device tolerance, and the sub-circuit only has one set of "typical" values. But they put all their faith in op-amps, don't they? Then there's noise gain which is nothing really to do with noise, but states that gain = 1 + (Rfb/Rin), yes, even in inverting mode! But they can't see that Rin inverting is to ground in noise measurement mode. But then again, that's true of non-inverting op-amp application, but the point is the 1 of 1 + (Rfb/Rin) is an error. Therefore the Rin gain switch used in so many op-amp RIAA stages, results in two different EQs, with one being perfected while the other can't be, and so either MM or MC EQ is out, and it's often the case that the MC was favoured. And so I make fixed gain RIAA stages, and they even scoff at that. The ignorance on show would be shameful except that the customer is usually blissfully unaware. |
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That none should be able to buy or sell without a smartphone and the knowledge in how to use apps
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Graham Slee
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Retired Joined: 11 Jan 2008 Location: South Yorkshire Status: Offline Points: 16298 |
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Posted: 26 Jul 2022 at 11:11pm |
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Shall we study the LF411? you can obtain the datasheet here: Single op-amps are the type we can get inside. Dual op-amps don't have balance pins. If you understand what balance pins do, then you know they affect open-loop gain, which is how to swing the differential input one way or another to null the output. That's a very good clue to what else they can do. One DIYer, Walt Jung, was interested in playing around with op-amps - after all, he designed a lot of them! I only know what I do because I studied things, and I think that's how education works, Jon? So for now, take a good look at the detailed schematic, and perhaps compare it with the designs of a modern dual-rail power amp. Then take a look at the bode plot and the open-loop frequency response and familiarise yourself with the semi-log graphs, the frequencies and the gain at those frequencies. By the way, to convert dB to linear gain, divide dB by 20, and take the antilog (base 10 that is). Try 40dB, 40 / 20 = 2, and the base 10 antilog is 100. |
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