The FU50 seems like an excellent tube, so how does the Sweet Peach FU50 amplifier sound like?
I can't find a review of the sound (or construction!) anywhere!!
It looks an interesting amp - so I'm wondering if it's worth a listen?
Does it go loud enough (my speakers are 88dB/watt)?
Is the bass any good? Midrange? Treble?
Does it favour a particular type of music?
Does it run hot?
Thanks in advance!!
P.S. There is also a rival "FU50 6AK5" amp that looks unfeasibly compact but the same SE deal - I wonder if anyone has tried that either?
I can't find a review of the sound (or construction!) anywhere!!
It looks an interesting amp - so I'm wondering if it's worth a listen?
Does it go loud enough (my speakers are 88dB/watt)?
Is the bass any good? Midrange? Treble?
Does it favour a particular type of music?
Does it run hot?
Thanks in advance!!
P.S. There is also a rival "FU50 6AK5" amp that looks unfeasibly compact but the same SE deal - I wonder if anyone has tried that either?
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I also found the compact weight to be a little discouraging too, tube amps are just heavy and the peach is about 3kg heavier. Mine does not run hot in the least but it will have to work a little to power your 88db speakers.
For what its worth the pc boards appear to be double sided but they are not so you can just jab each of the solder joints with a iron and swap components without removing the boards. I replaced the "Wima" coupling caps with Vishay Roederstein MKP's of the same value, also replaced all the series grid resistors with Vishay Beyschlag metal film. Bicolor, I was going to change the plate and cathode resistors for the 6n1p to favor a steeper load line and bias the tube to a higher idle current but after looking at the 6n6p with the stock plate and cathode resistors I figured I could live with what I saw for a while. Its hard to say how the changes have affected the sound as I haven't had the amp playing for probably close to 2 weeks that and the new pieces need at least a handful of hours to break in, so far sounds fine.
For what its worth the pc boards appear to be double sided but they are not so you can just jab each of the solder joints with a iron and swap components without removing the boards. I replaced the "Wima" coupling caps with Vishay Roederstein MKP's of the same value, also replaced all the series grid resistors with Vishay Beyschlag metal film. Bicolor, I was going to change the plate and cathode resistors for the 6n1p to favor a steeper load line and bias the tube to a higher idle current but after looking at the 6n6p with the stock plate and cathode resistors I figured I could live with what I saw for a while. Its hard to say how the changes have affected the sound as I haven't had the amp playing for probably close to 2 weeks that and the new pieces need at least a handful of hours to break in, so far sounds fine.
In a sense I feel the same way about my amp. I have only changed the stock tubes for russian tubes, and that alone made quite a difference.
I will relax for a while and listen some more. If changing the plate and anode resistors of the 6n1p can make it sound better I am all for it, though it's ok as it is. Also I'll try using a 6n23p
How do you know the schematic of the SoundTrack Amp???
All I can find with extensive Googling was one fuzzy picture of the front
Please share if you have them!
It is lighter and more cramped true, but it would (physically) fit into my system more easily and maybe the wife would not even notice it's arrival?
BTW this amp would be replacing an Usher R1.5 (150W class A) amp driving Usher X708 speakers - so an SE tube is quite a different proposition in sound - what do you think the main difference in sound should be?
(Asking (different questions) on the 'any good chinese amps thread too - sorry for any duplication).
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I honestly know nothing about the 6AK5 except that it is a pentode, I think most would assume it is triod strapped as there is generaly a predjudice against pentodes in the Hi-Fi world, but I agree with Mazuki that the 6n1p and its cousins would probably offer easier/ cheaper tube rolling plus they are already triodes.
I think we are at least a little biased (he he) in our opinions of the Sweet Peach VS XX because we own them. As far as power goes, I too was a little concerned that a pitiful 13watts could compete with my mamoth Onkyo or AMC amps but the GU50's effortlessly power my B200/HI-VI ribbons to painful levels. The amp is brutaly honest so the gentle background hiss from older recordings is exposed, lousy recordings sound lousy, good ones sound spectacular. Movies sound excellent, I never was a surround guy but I find using a tube amp for films is great because of all the midrage content. I researched different Chinese amps for months before pulling the trigger on the Peach so I understange your desire to make a prudent decision. I was also considering the Soundtrack FU50 but at 8kg(?) it was just to chintzy and the form factor followed the trendy "narrow but deep" look, the Peach was more conventional and I find that this pragmatic, tasteful attitude is consistent throughout the design, no stupid wooden cheecks or gaudy blue LEDs hidden beneath the tubes, just an ebarrassing name
I think we are at least a little biased (he he) in our opinions of the Sweet Peach VS XX because we own them. As far as power goes, I too was a little concerned that a pitiful 13watts could compete with my mamoth Onkyo or AMC amps but the GU50's effortlessly power my B200/HI-VI ribbons to painful levels. The amp is brutaly honest so the gentle background hiss from older recordings is exposed, lousy recordings sound lousy, good ones sound spectacular. Movies sound excellent, I never was a surround guy but I find using a tube amp for films is great because of all the midrage content. I researched different Chinese amps for months before pulling the trigger on the Peach so I understange your desire to make a prudent decision. I was also considering the Soundtrack FU50 but at 8kg(?) it was just to chintzy and the form factor followed the trendy "narrow but deep" look, the Peach was more conventional and I find that this pragmatic, tasteful attitude is consistent throughout the design, no stupid wooden cheecks or gaudy blue LEDs hidden beneath the tubes, just an ebarrassing name
Thanks that's useful info. The FU29 amp you suggested looks interesting too!
Does it really do MM phono? If so have you tried it?
What's the biggest difference in sound between your mammoth Onkyo and the Sweet Peach?
And most importantly - which amp do you prefer to listen to?
BTW I think I found the Soundtrack amp here, made by Guangzhou Zhuo Sheng Electronics Factory, late november last year.
Net weight stated is 9kg in the summary and 8kg in the text!!, so that is either 1kg or 2kg lighter than the Sweet Peach, which is more believable. Only has 8ohm outputs I think too.
So I found it but I'm no wiser
Does it really do MM phono? If so have you tried it?
What's the biggest difference in sound between your mammoth Onkyo and the Sweet Peach?
And most importantly - which amp do you prefer to listen to?
BTW I think I found the Soundtrack amp here, made by Guangzhou Zhuo Sheng Electronics Factory, late november last year.
Net weight stated is 9kg in the summary and 8kg in the text!!, so that is either 1kg or 2kg lighter than the Sweet Peach, which is more believable. Only has 8ohm outputs I think too.
So I found it but I'm no wiser
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The mm phono input of the Sweet peach is nearly useless, the sound quality is horrible so it is best to hack out the phono stage and wire it through as another auxilliary input. My Onkyo is fairly powerful but completely uninvolving, micro details are almost nonexistent. The Sweet Peach is the best amp I have , depending upon the source the weight is between 10 and 12kg. Seems to me you have your heart set on the Soundtrack, give it a shot, it can't be that bad.
Thanks for the info. I didn't see the phono on the schematic so I guess it is solid state?
Tending more towards the Sweet Peach actually, I was worried about the size but it seems quite compact and looks far better for DIY mods.
I like the FU50 tubes too and do not want to spend too much, I have external phono so I can bypass the built in one. Just one more question: What is the bass and punch for rock like on the Sweet Peach?
Tending more towards the Sweet Peach actually, I was worried about the size but it seems quite compact and looks far better for DIY mods.
I like the FU50 tubes too and do not want to spend too much, I have external phono so I can bypass the built in one. Just one more question: What is the bass and punch for rock like on the Sweet Peach?
Yep, the phono stage uses literaly a no name opamp based circuit, very low end. I wish I could give a better assesment of the bass but I have mine paralleled into the high impedence inputs on my sub but subjectively it seems deep and punchy, my sub is not exactly a star performer though and this arrangemnt is not optimal by any means. The tube compliment is as economical as it could possibly be, soviet replacements are good quality and very cheap.
Oh an op-amp phono, I have one in a Revolver Phono2 that sounds extremely dull, but I may update that for a decent chip.
I have an external tube phono stage arriving however so if I get the Sweet Peach (SP) I'd clear that out straight away.
I guess it needs the usual re-biasing, anode fuse fitment etc. that cost of Chinese amp demands?
The minimal tube count is interesting as the SP top-plate looks like you can make your own and fit it - i.e. DIY interchangeable driver sections! I have mullard ECC88s coming out out of my ears here, from an old tektronix scope.
Understood about the sub, lets hope someone reading has tried it with rock into average (88dbish) speakers. I figured (based on listening tests with a voltmeter verified by an SPL and calculations) that I need 9W RMS for music here, so in power terms this SP amp should suit me fine. I guess I'm really asking if the SE topology + the supplied output transformers are up to the job - but at this price point I may be asking for too much
I have an external tube phono stage arriving however so if I get the Sweet Peach (SP) I'd clear that out straight away.
I guess it needs the usual re-biasing, anode fuse fitment etc. that cost of Chinese amp demands?
The minimal tube count is interesting as the SP top-plate looks like you can make your own and fit it - i.e. DIY interchangeable driver sections! I have mullard ECC88s coming out out of my ears here, from an old tektronix scope.
Understood about the sub, lets hope someone reading has tried it with rock into average (88dbish) speakers. I figured (based on listening tests with a voltmeter verified by an SPL and calculations) that I need 9W RMS for music here, so in power terms this SP amp should suit me fine. I guess I'm really asking if the SE topology + the supplied output transformers are up to the job - but at this price point I may be asking for too much
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Yes - there appears a big disparity with the schematic voltages!
Yours is (400-210) = 190V across 47k = 4.04mA
So the grid voltage is -4V, which may work with a 6N1P but not with an ECC88 which would need -6V at 200V and 4mA.
Yes you are right - that's the ECC88 out then. The 6n23p is 300V, Doh!
I have looked at the 6n1p and the 6n6p datasheets and they do not seem to match that well with the 200V anode either.
The ECC82 seems a nice fit if you double the cathode resistor however, although it looks perhaps even better with a CCS in place of the resistor. Must be something wrong with it though - perhaps the gain?
Why do the 6n6p and the 6n23p sound better than the 6n1p? I'm puzzled!
ETA: This link suggests that 47K and 1K give the lowest THD, but of course the actual harmonics matter to us rather more than the total. So I'm puzzled why this is sub-optimal!
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Got my Sweet Peach today, with what look like FU-50s for it. Looks nicely built actually, and the FU50's look very solid. I notice the FU50s can install at 180 degrees too, but I guess the raised glass bar faces toward the transformers.
It's marked for 230V and I have 220 and 245 available - any preference?
Also I'll need to bias the FU50s - I'll check the thread but I got zero instructions with mine so thats my only thing to check!
It's marked for 230V and I have 220 and 245 available - any preference?
Also I'll need to bias the FU50s - I'll check the thread but I got zero instructions with mine so thats my only thing to check!
I'm really happy you got it home in one piece, quite quick delivery!
And you are correct about the output tubes, mine have the glass bar facing the transformers.
I have not biased mine, as I am not all that comfortable with high voltages and I also lack experience. Only amp I have ever biased was a pair of Dynaco mk3's.
I hope you will be happy with the peach after making some changes to it.
So far my amp has been modified with changing all the tubes to russian. One 6n6p, two 6n3p and two GU50. Other than that, I followed S.Spielbergo's advice and replaced the 0.1uF wima coupling caps with better quality mkp coupling caps.
6n1p, 6n23p, 6n6p... there are options that's for sure... I am still thinking about changing the anode and cathode resistors and trying the 6n1p again. But not right now, I kind of like the signature it gets with the 6n6p.
Oh and I also replaced the blue LED and it's resistor (think it was a 47k) with a regular white LED behind a green lens to give it a nicer appearance. The voltage there was quite high, 18-20V if I remember correctly.
To get it to light up properly I did not calculate and measure voltages, I simply took various resistors until I was pleased. I went with 1,2k. (with the same LED I use 470 ohms for 12V).
And you are correct about the output tubes, mine have the glass bar facing the transformers.
I have not biased mine, as I am not all that comfortable with high voltages and I also lack experience. Only amp I have ever biased was a pair of Dynaco mk3's.
I hope you will be happy with the peach after making some changes to it.
So far my amp has been modified with changing all the tubes to russian. One 6n6p, two 6n3p and two GU50. Other than that, I followed S.Spielbergo's advice and replaced the 0.1uF wima coupling caps with better quality mkp coupling caps.
6n1p, 6n23p, 6n6p... there are options that's for sure... I am still thinking about changing the anode and cathode resistors and trying the 6n1p again. But not right now, I kind of like the signature it gets with the 6n6p.
Oh and I also replaced the blue LED and it's resistor (think it was a 47k) with a regular white LED behind a green lens to give it a nicer appearance. The voltage there was quite high, 18-20V if I remember correctly.
To get it to light up properly I did not calculate and measure voltages, I simply took various resistors until I was pleased. I went with 1,2k. (with the same LED I use 470 ohms for 12V).
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