Ahh yes, they used resistors on pots between the wiper and ground as a law faking resistor. When used with a high value linear resistor pot say 100-200Kohm and you use say 10-22K resistor it allows better left to right matching and acting as a Logarithmic type. It was a trick used in 70's-80's as a result of poorly L-R matched Logarithmic types.
Here resistors are straight between input and ground. So these are in paralel with entire pot - unless pot is applied differently than usually... So what is the sense for that? No idea!
That was the only explanation I could see. It just doesnt make any other sense and it looks like last stage unexpected addon. But the pot is really cheap and its really, really linear and thus BOOOOORING.
You are very humble and yet, you are and awsome reviewer. Well structured, great content. Still waiting for your chart that you could have on a website linked to your channel like I've seen for other content type.😊 Thx for considering that.
Thank you! That's actually a very good idea! I'll think that through, should be easy, the problem is that Q3 is always hectic in the office and I'll have some free time only just a few days before Christmas. But this definetely goes on my list!
This review was indeed a pleasure. Apparently, there is a place for AI. That is in determining the genre and characteristics of a song about to play and amp-switching to the correct one based on rock, choral, dynamics, bass, etc. That can be your next project! Thanks for the recommendation of Sylvia Hotel, Human and Baba Yetu (the Lords Prayer, see also diff version by Aquabella). Great job!
@@EvenHarmonics I was thinking about doing a video on tracks that I use for my tests, as I could explain what to look for in them and why these are IMHO great as benchmarks. And they are great music too:)
Very nice video... thank you..... if we are not talking about money... just about quality of sound and soundstage overall - which one from those you reviewed up until today, you would prefer or choose most of the times for all day listening? jazz, blues, ambient electronic music.. no heavy metal and similar
@@annebokma4637 thats coming but I need to review all of them, the worst thing would be to do a ranking and then insert something in the middle or at the top later on (id expect crowds with torches and spikes at my door then)
For those, I guess something like FM300A, E405 and - low power! - MF A1, JLH1969 (the one I tested!) or this baby. The others are faster, harder, more 3d maybe, but these will shine in everything mid range. The most relaxed and probably best match would be E405 - most expensive of the bunch!
@@k4syx nobody complains about the hot 100 and that changes all the time 😁 besides your work will never be done. And a running indication of your preference (and specially disliked) can give someone who wants to buy now a valuable resource. Just my 2 cents , keep up the good work 👍
Very cool! 😁 A friend of mine bought a Dart Zeel amp clone from LHY. It's heavy as hell and the parts and casework are top shelf. LHY charges considerably more for their version ($1600/$2100 shipped) but it sounds superb.
Another very insightful review. Great! :) I have two questions: 1. So the Marantz clone is more refined in sound (detailed) thane Burmesters clone after removing those resistors? 2. Will you also remove a volume potentiometer from JLH 1969 circuit , so making it a true power amp? What can bring this to the sound? I am thinkng to try with mine amp, but I am not an electrician. But there are some specialists for hi-fi...
@@majtextwriter1794 Thank you! Yes I think Marantz clone is more refined, 933 is wilder, so the music genres play a role here too. I wasn't thinking about bypassing volume pot on 1969 as I thought that it may be handy in such a small desktop amp. I'd have to take a look inside of that's something as easy as it was with Musical Fidelity A1 clone
This one reminds me of old Heed/Naim shoe-box amplifiers. I received my FM255 clone preamp yesterday by the way. Dead silent background and it sounds awesome. Looking forward to your review as the design of mine is not exactly the same as yours.
@@k4syx it is my hobby but this is not all .. I want the best but I have limited budget and time ..I was satisfied with the vintage gears but the TPA informed me the technology change and market change .. We all know $250 is nothing in this hobby .. but will I put half a million to buy the ultimate unit .. no I will get a better return from buying a rental house to create cash flow ...still I have limited budget and time .. I will still get the best ultimate unit or units for myself ..
Again, thank you for your effort! Just curious about some of those caps. They don’t look new. Do you know where the manufacturer is scavenging those parts from?
No these look fine actually, but yes, in Musical Fidelity A1 clone and 1969 Hood they definetely used some recycled caps. Which is fine by me, Id rather take recycled EPCOS than brand new Sangxwa (or any other of many very very cheap caps)
Price I guess! you can get these in DIY with mono PCBs, but fore ready made device 2 monos = 2x chassis, 2xpower supply so the price goes significantly up. And then going with two monos would also beg for best possible quality parts because if not, then theres no sense in going this way anyway :D
Is there any value in getting a second set of ‘fins’ for the left side from the manufacturer, as the amp is not too large, or would that not help significantly in the heat dissipation.
@@EvenHarmonics No I dont think so, the other side is quite cool, its far from power transistors. I think rotating the ampand heating to get them to topside may help. Gotta try that over the weekend!
Another great review, thank you! I'd love to hear some reviews on other clone monoblocs if you get the chance - I was really hoping this one was available in mono configuration
Not yet. I need to review two preamps more that I have in line. But so far, both Cary and JC2 would be very good choices as this Marantz clone is neutral. Maybe with a little nudge towards Cary (you can get it in silver) as you may scale it with tubes later too.
@@k4syx Audioholics: MartinLogan Motion 35XTi Bookshelf Speaker Review Minimum impedance: 5.5 Ohms at 180 Hz. True 88.2 dB/2.83V/1m sensitivity. Easy to drive. 🤔 [ The above graphs show the electrical behavior of the MartinLogan 35XTi speakers. MartinLogan characterizes these as 4-ohm speakers, and I find that to be a very conservative rating. They could easily have specified these to have a 6-ohm nominal load, and I would not have argued. The minima occur at 180 Hz at just a hair under 5 ohms, but that is with a not-terrible phase angle. Most amplifiers, even cheap ones, should be able to drive these speakers just fine. This might be a tough load for a cheap amp to push at a high drive level for a long time, but other than that, it’s not something to worry about (not that anyone is going to use a $1,300 speaker set with an entry-level amplifier). Port tuning looks to be a bit above 60 Hz. I measured the 35XTi speaker’s sensitivity at 88.2 dB for 2.83v at 1 meter which is lower than MartinLogan’s spec of 92 dB for 2.83v at 1 meter. That is a fairly significant difference, but 88.2 is still a bit above average for bookshelf speakers in this class. ]
Thanks! The current one looks like laser engravement, you'd need to sand the whole panel to remove that. Doable. And you can add your thing the same way.
Much enjoyed, but hope you don't mind my asking a few questions: 1. What class is this amplifier? 2. Do I understand you correctly that this amp uses only a little more power than an old 60W incandescent light bulb did? If so, that's not at all bad - about the same as my class A preamp. 3. Again, and just to be sure, to get the best out of this amp, is essentially the main thing to cut the two resistors you mentioned? Incidentally, they won't deliver to the UK from the shop you link to, but other shops on Aliexpress will.
The old Marantz was an AB, if I remember correctly. With 300w I can't imagine it being any other kind. This clone is based on that and doesn't get hot or use a boatload of power, so AB too
Its AB, though I've found some info that orignal (and maybe this one too) was biased to be in class A for lower output power. Yes its quite efficient when it comes to power requirements (with my listnening levels). Yes cut them and loose them :)
@@k4syx now that class A with lower power would be very interesting. I didn't get what estats you have. It is a bit heavy for the ESL 57 and a bit light for the acoustat x.
@@annebokma4637 he has Martin Logan Ascent Electrostatic speakers he is hoping to drive well on this journey. I have ‘Theos’. Others, please comment if you have electrostats
Ouch thats a very tough question. Monos are faster, a little more detailed, but this one has better imaging. And monos require better opamps to sound best. But they also use less power and are smaller, and cooler. A good one, I will have to compare them head to head. I am planning to do summaries for amps in the same or similiar price brackets so something like that is coming here.
The Chines makes an error by construction: The Speakter Protection-Board must to the Backside and the Transformer to the front, so the cable ways will be very shorter and the sound will be bether, too.
I'm enjoying your video's,I primary building Amplifiers,Power Supplies along with DACs while experimenting with SMPS over Linear. Using separate boxes change everything PreAmp, Amps,DACs all have top performance with separation from heat & EMI and common mode noise. Input matching is problematic in Audio.. and example is matching a water hose with running water into another without a spilling
Are they trying to lower the input impedance to stop noise or keep it from varying dependent on the volume setting, or if you directly connect it to the power amp board there will still see a load.
@@k4syx Could be some weird hf/r.f oscillations without it. They must have needed it, perhaps for reasons that are not immediately obvious. 47k would be easier to understand.
@@johnshaw359 yes I was going over it again and again and I cant get to anything better than making pot logarithmic. Everything works fine without them and it sounds waaay better too.
Yes choosing the right word is tricky here. These are not 1:1 copies (with some exemptions) but they are based on original designs: just with redesigned PCBs to fit DIY build and sometimes modifications based on experiences of the guys that have built them. These are mostly floating (schematics) over diy forums. This one has lower power output: some output power transistors pairs were removed leaving just two per channel
😢😢😢Apologies for this comment on this review but I thought it would have more chance of being ready . Well it finally arrived my MF A1 despite the tracking saying it was going back and forth between NL then UK then back to NL. I never thought it would arrive but it has and unfortunately it doesn't work, well it half works!!! The right channel sounds good already but no sound from the left channel. When switched on both LEDs flash, relays click and the amp is good to go but only one side of the chassis. The RHS gets warm not hot my V3 mono's get significantly hotter when using RCAs. But alas the LHS stays stone cold. Already the soundstage width is impressive, it's just a shame its mono!! When switching off the LHS LED flashes a lot longer than the RHS. If anyone can offer solutions that would be great. It's beautifully built and robust and although it was well packed in it's box complete with RCA cables, I also ordered a BRZHIFI L1 preamp which was again packed well. However both amps were packed in a larger box with no padding so would have moved around a lot in transit which may have caused the problem. I'm gutted as I've been so looking forward to receiving it. What should I do now? Do I raise a complaint with AliExpress and it's then up to them to resolve the issue with the BRZHIFI Official Store. How do disputes normally get resolved? This is only my second issue buying from AliExpress. By the way the BRZHIFI L1 class A preamp is working beautifully with the V3 monos and hopefully when I replace the NE5532 opamps with OPA828 it will work even better. Any advice would be gratefully received.
Yes contact the seller and describe the issue. Which shop was that one from? The one I recommended? Explain the problem, maybe record and send video and go for refund. In case of problems ask Ali to step in (it's all very easy actually and semi automatic when you open dispute). But before opening dispute just contact the seller. Ahhh and if you have any experience in the area remove the top lid and look for obvious problems like something disconnected, these sometimes have rough times in shipping
Hi. Thank you for your response. I will contact BRZHIFI Official Store first to see what can be done. I would really like a replacement as I think the A1 is a great amp and I have been running it in anyway and I love the sound as the soundstage is very wide and I'm starting to hear things I hadn't heard before in my auditioning tracks. My biggest concern is the cost of returning it to China and the length of time to get a replacement. If they agree I will open up the A1 to see if there is an obvious loose connection. Many thanks for your recommendation, my first impressions of the A1 is that it is beautifully built, despite the fact that only half of it works, and it's sound will only get better. Keep up the great work you are doing you are gaining followers all the time and the Chinese clone producers must be very pleased with your channel and recommendations. Have a great weekend.
I'm looking at purchasing this amp now. one question, I plan on putting it on a wifi plug so I can power it on and off remotely and leaving the amp switched on. I understand powering the amp on and off like this by cutting the power could/will shorten it's life, but I this price I can live with that assuming I can get some years of enjoyment out of it. what are your thoughts on that? thank you sir!
I do the same thing using Tuya smart sockets. It doesnt matter for amps etc that have mechanical switches because you're doing exactly the same thing as switch and in arguably more controlled way :D
@@k4syx excellent, I'm planning on purchasing a wiim ultra streamer and running it into the inputs for a basic office system. so power consumption it's basically 6 watts idle and approximately 35 to 60 watts based on volume?
Make sure your wifi plug can pass 1.5A current minimum. If power transformer is rated 300VA, by 230V mains, you may draw up to 1.3A current when it plays loud and orchestra play tutti!...
@@rainham1 no when it's idle it's 60 and when playing it's 61-62. It's still low for an amplifier, but not so low that I would leave it on all the time. The switch on the front plate cuts the power completely. It will be a great office setup!
@@k4syx It is 41.49. Just interesting, I see other reviewers adding some sample of playing musing on the amplifier. Is it interesting for viewers on your opinion? Or on RU-vid you won't get any difference? BTW - exceptional review and very interesting model. It is also might be interesting a power consumption between idle and average load.
@@ruslanmulyk8601 Thank you. When its noticable I am giving numbers on load/idle, here it was like 60 vs 61.5W so nothing significant. That amp is FM801 clone thats currently burning in - the chassis is the same as for DartZeel clone but this is FM clone. As for music samples. I am working on a set that would be able to record anything with acceptable quality, I already have ADC and I am waiting for matching pair of instrument microphones. The problem here is that mic (a good one) will have like 80dB SNR, ADC is 96dB here, and both of them have a frequency response thats not exactly flat (mic especially). Getting that flat would require EQuing the recording, which would make the whole process moot. And on top of that I'm trying to get recorded differences between amps having 0.005%THD and SNR in range of 120dB. I will try, as its fun and much to learn, but my brain whispers to me that it will be pointless because the mic will always be bottleneck and common denominator for all amps here: that what you will actually hear will not be traits and qualities of amp itself but the microphone. But Im not giving up!
Overall, yes. Closely followed by few others, depending on your music tastes some may be slightly better in some areas and slightly worse in others. I'd say that this Marantz reminds me of DartZeel in general sound presentation.
In a way, these are originals too. This is not a 1:1 copy. Its based on ideas and scheme of Marantz but its repurposed to be smaller, stereo, less output power and CHEAPER.
The shipping will vary by the country, I've seen that. Wait for some coupons - 11.11 is quite soon, and if you're EU based check the actual final price just before the payment as at that stage the price gets reduced by 23%VAT - in my case it usually covers while shipping fee all in all.
Good question that I've answered somewhere in the comments already :) I think this one has better 3d, TPA monos are on the other hand slightly faster and more detailed. But if you want them to sound this analog way as this Marantz clone, you need to invest in some class A discrete opamps and then it gets pricier. All in all I'd say these are trading blows here as equals. No clear and obvious winner by knockout.
@@igoryakunin685 oh I thought you were asking about tpa monos I was reviewing in my channel earlier. If youre asking about A70-like amps this beats them with no sweat. different league (at least for now, I strongly believe in d class future)
