Misternavi Posted June 8, 2018 Author Share Posted June 8, 2018 i love the clear top. is it glass or plastic? 1 Link to comment Share on other sites More sharing options...
PoisonM Posted June 8, 2018 Share Posted June 8, 2018 On 2/06/2018 at 9:23 PM, metal beat said: Why not go the whole hog and buy a fake FM Acoustics amp? https://www.aliexpress.com/store/product/Study-Copy-FM-ACOUSTICS-FM711MK2-power-amplifier-250W-2-8-ohms-about-99-Direct-cloning-amp/1070003_32802913825.html?spm=2114.12010612.0.0.659e3af7z0ZW7Q That's a pretty impressive clone. Some thought must have been put into it since they changed the speaker binding post to normal ones. The original FM post wouldn't be unusable to most. Link to comment Share on other sites More sharing options...
MattyW Posted June 8, 2018 Share Posted June 8, 2018 46 minutes ago, misternavi said: i love the clear top. is it glass or plastic? That's a smoked glass top 2 Link to comment Share on other sites More sharing options...
THOMO Posted June 8, 2018 Share Posted June 8, 2018 Or pre-smoked? Sorry I couldn't resist it! 1 Link to comment Share on other sites More sharing options...
Misternavi Posted June 8, 2018 Author Share Posted June 8, 2018 That's a smoked glass top [emoji4]i want! 2 Link to comment Share on other sites More sharing options...
Volunteer sir sanders zingmore Posted June 8, 2018 Volunteer Share Posted June 8, 2018 12 hours ago, MattyW said: I believe the power capacitors take a week or so to fully charge My knowledge of these things is not great, but that sounds like an awfully long time 1 Link to comment Share on other sites More sharing options...
MattyW Posted June 9, 2018 Share Posted June 9, 2018 4 hours ago, Sir Sanders Zingmore said: My knowledge of these things is not great, but that sounds like an awfully long time My knowledge of the working of these things is pretty well non existent. I was just regurgitating some half remembered part of what a reviewer found on the actual genuine product. There's no telling how this unit will change with burn in Link to comment Share on other sites More sharing options...
MattyW Posted June 9, 2018 Share Posted June 9, 2018 5 hours ago, THOMO said: Or pre-smoked? Sorry I couldn't resist it! Lol. It hasn't gone boom yet. build quality seems really rather good so hopefully it won't. Link to comment Share on other sites More sharing options...
Al.M Posted June 9, 2018 Share Posted June 9, 2018 (edited) 23 hours ago, MattyW said: Ok I recieved my darTZeel NHB-108 copy today. I must say that I've never seen something so well packed before. It would really take a bit to damage it the way it was packed. Took near a half hour to get it unboxed. Weighs an absolute tonne. After first power on there was noticeable hum in the transformer and through speakers which disappeared after 5 minutes or so. I believe the power capacitors take a week or so to fully charge. First impressions were.... Why did I change from the Quad. Another half hour and it is clearly a better amp. Very natural sounding. Sound stage width and depth is entirely reliant on the recording. Sounds like a tube amp in terms of its tonality and presence though has the detail, speed and bass impact of a solid state amp. All up not bad. I don't expect it to be at its best for somewhere between a week and a month. Another 15 minutes have gone by.... This is the best I've ever heard my system, and it's barely begun to burn in. Damn. With many songs it's like I'm just hearing them for the first time. There's details here I never knew existed. Well done, incredible looking clone. As I mentioned in previous post about the cloned Goldmund amp I bought for $700 delivered no regrets, the CAT preamp was quite good but I returned it and received a full professional refund including the postage. On eBay for $800 v1 or $1000 v3 plus delivery is pretty good. Edited June 9, 2018 by Al.M 2 Link to comment Share on other sites More sharing options...
MattyW Posted June 9, 2018 Share Posted June 9, 2018 (edited) Yes, I'm very happy with this unit I have found it has some low level hum if your within a foot of the speakers. Not audible from my listening position though. Edited June 9, 2018 by MattyW Link to comment Share on other sites More sharing options...
Volunteer sir sanders zingmore Posted June 9, 2018 Volunteer Share Posted June 9, 2018 53 minutes ago, MattyW said: Yes, I'm very happy with this unit I have found it has some low level hum if your within a foot of the speakers. Not audible from my listening position though. There goes my idea of trying one. Darts are meant to go well with horns but hum is a killer Link to comment Share on other sites More sharing options...
MattyW Posted June 9, 2018 Share Posted June 9, 2018 48 minutes ago, Sir Sanders Zingmore said: There goes my idea of trying one. Darts are meant to go well with horns but hum is a killer I'm going to try testing with a DC trap, also a 240 to 220v step down transformer. Might be something like that. I've had that with other gear before. Heck, might even be self interference. My version doesn't have the internal metal walls to stop each section (power, left and right channels) interfering with each other Link to comment Share on other sites More sharing options...
Addicted to music Posted June 9, 2018 Share Posted June 9, 2018 1 hour ago, MattyW said: I'm going to try testing with a DC trap, also a 240 to 220v step down transformer. Might be something like that. I've had that with other gear before. Heck, might even be self interference. My version doesn't have the internal metal walls to stop each section (power, left and right channels) interfering with each other Try basic things first, although it looks impressive, it’s not doing it a lot of favours having a glass top. Then you place it next to a TV that is heavily using regulated SMPSU. Move it on the floor for process of elimination and try a metal plate on top. Also if your using RCA alternate and used the XLR. The hum via the transformer on switch on is normal as the those massive filter caps are discharged and represent a short to the mains. After switch on it should take more than a few seconds to subside. If it’s taking 15 mins it’s too long but that will depend on the idle current and the bias set. Link to comment Share on other sites More sharing options...
Al.M Posted June 9, 2018 Share Posted June 9, 2018 The CAT clone preamp I had sounded very good, easily as good any mid to upper level preamp, but there were several minor issues that made me decide to return it: 1. Transformer hum audible slightly from about 3m, at 30cm distance the hum was about 3dB above background noise. I didn’t try a DC blocker. My house is quite old and my system setup often also has noise issues with equipment. 2. There was a cosmetic manufacturing fault in the casing from warped base casing. 3. The casing wasn’t designed that well to ventilate heat. 1 & 2 might have been addressed easily but 3 needs a casing design change by having vent slots or grill at the bottom of the casing. For $700 delivered I doubt any commerical retail preamp would have sounded as good. It may have run in if I kept it longer than 2 weeks but the sound was also too bright for me. 1 Link to comment Share on other sites More sharing options...
MattyW Posted June 9, 2018 Share Posted June 9, 2018 There's no way I'm sending this back. After an extra day of use I've never heard anything quite like it. Even if I can't sort out the low level hum, I can live with it. This thing is nothing short of spectacular 4 Link to comment Share on other sites More sharing options...
MattyW Posted June 10, 2018 Share Posted June 10, 2018 Interesting. I put a DC trap before the amp and I've no more hum. We've some light industry in our area. I'm guessing DC current feeding back from electric motors through the power grid. It seems these copies are sensitive to DC current. If I put my ear right up to a speaker there is still the faintest little bit of hum there. I suspect they've used transformers for 220w mains rather than 240v. If I could be bothered I'd source a 240v to 220v step down from TorTech. With these speakers though it really is unnecessary. If I were using 100+db sensitive speakers though it would be a different story. 1 Link to comment Share on other sites More sharing options...
Al.M Posted June 11, 2018 Share Posted June 11, 2018 (edited) On 10/06/2018 at 9:16 AM, MattyW said: Interesting. I put a DC trap before the amp and I've no more hum. We've some light industry in our area. I'm guessing DC current feeding back from electric motors through the power grid. It seems these copies are sensitive to DC current. If I put my ear right up to a speaker there is still the faintest little bit of hum there. I suspect they've used transformers for 220w mains rather than 240v. If I could be bothered I'd source a 240v to 220v step down from TorTech. With these speakers though it really is unnecessary. If I were using 100+db sensitive speakers though it would be a different story. I regard some small residual hum up close to a speaker is acceptable and normal, especially a power amp at full with no volume control on it. Its possible to come across used 240v to 220v transformers around the place for $40, I used to have 3 of them but gave my last one away with gear I sold. Edited June 11, 2018 by Al.M 1 Link to comment Share on other sites More sharing options...
MattyW Posted June 11, 2018 Share Posted June 11, 2018 Yeah, I'm just going to stick with the DC trap I think. Sounds great to me Link to comment Share on other sites More sharing options...
stevoz Posted June 12, 2018 Share Posted June 12, 2018 (edited) Post edit.....wrong thread! Edited June 12, 2018 by stevoz 1 Link to comment Share on other sites More sharing options...
MattyW Posted June 12, 2018 Share Posted June 12, 2018 1 hour ago, stevoz said: Post edit.....wrong thread! Lol. I've done that a few times Link to comment Share on other sites More sharing options...
Guest Muon N' Posted June 12, 2018 Share Posted June 12, 2018 (edited) @MattyW If you remove the cover on that power transformer you should see if it's 220vac , 230vac or 240vac, should be labeled. Edit: but be careful of the big filter caps in case they are holding a charge. Edited June 12, 2018 by Muon N' Link to comment Share on other sites More sharing options...
MattyW Posted June 12, 2018 Share Posted June 12, 2018 I'll be staying out of the insides of this thing.... I'd like to live a few years yet Maybe in 10-15 years I'll get it recapped though that will be it Link to comment Share on other sites More sharing options...
MattyW Posted June 17, 2018 Share Posted June 17, 2018 She's a lovely thing to look at 1 Link to comment Share on other sites More sharing options...
mocenigo Posted August 7, 2018 Share Posted August 7, 2018 (edited) On 17/10/2017 at 11:08 AM, stevoz said: ....vs the knock off: Laughable really. Actually, not. The actual boards of the original and of the clone have been compared in several fora (esp in Italy on the Melius boards where there is an ongoing attempt to upgrade the amp by allowing more current, stabilisation, and separate power supply for the input stage of the amp) and they have been found to be really 1-1 the only difference being the output devices of the MJL4* series instead of the arguably better MJL3* of the original. The difference is small and it is easy to replace them. The front boards are for thermal and safety circuits (which are replaced by simpler ones in the clones) and also contain the circuitry that makes the "eyes" glow in rhythm with the music - I do not care if the clones do not contain them! At the back the original NHB-108 has a board with a Neutrik unbal transformer to convert the balanced signal to an unbalanced one - these are missing from most clones (together with the BNC 50Ohm circuit) and the transformers are the same that are contained in some very cheap D shaped adapters from Neutrik. The biggest significant differences are thus in the power supply. Some models have a lot of smaller capacitors, the intermediate ones have two big (34000 pF) cans or 4 of the same cans of the original (which has 6, with gold (!) moon shaped bars to connect them). There is always debate on much capacity you need. However, the chinese manufacturers can provide also versions with 2 x 800VA transformers, 6 cans per channel with gold plates pure copper connections bars, XLR input with Neutrik 1:1 line transformers and even some self brewed circuitry to make the eyes glow in rhythm with the music. But apparently the reviews are in for the intermediate models with 2 larger cans and no XLR input, and they are very good. Ethical or not, many choices in audio design have diminishing returns (such as increasing filtering capacitance) and leaving these off can still give you an excellent product. Also, when a design is 20 years old any IP on that has expired – and the reason patents do not last forever is to guarantee that nobody has an eternal monopoly on their ideas. Edited August 9, 2018 by mocenigo Fixed a couple of typos, added a few additional comments 2 1 Link to comment Share on other sites More sharing options...
mocenigo Posted August 7, 2018 Share Posted August 7, 2018 On 21/11/2017 at 3:31 AM, aasza said: I find it hilarious that Apple and Samsung are always taking each other to court over patents and arguing over who designed what tech first considering.... THE GALAXY AND iPHONE ARE MADE SIDE BY SIDE IN THE SAME FACTORY IN CHINA.... And? Link to comment Share on other sites More sharing options...
Recommended Posts