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Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 08 Nov 2017, 15:25
by Ichabod_Crane
Hi, J0K3RX. When you have looked the board can you take some pictures or tell us the technical specifications of the PSU.

I'm waiting. :wink:

Thank you!

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 09 Nov 2017, 18:00
by J0K3RX
Ichabod_Crane wrote:Hi, J0K3RX. When you have looked the board can you take some pictures or tell us the technical specifications of the PSU.

I'm waiting. :wink:

Thank you!
The power supply is an 18v DC / 1.5A... The pic is the exact make/model WT1801500

inside the pedal the 18v power from the power supply goes directly to the TDA2003 power amp and also splits off to a 78L09 voltage regulator going to the preamp.

Did anybody happen to see these? :twisted: Looks like they have ENGL Savage, SLO 100, Friedman BE 100, Bogner Shiva and the 5150 now!
http://www.hotoneaudio.com/products/nanolegacy/

They replicated a fukin Bogner Shiva over the Uberschall? Wtf is up with that? :evil: and they named it Siva Boogie...? stupid ass name...

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 09 Nov 2017, 21:07
by Ichabod_Crane
Thanks!

The 78L09 for the preamp is the thing I was considerng for my project, maybe a 78L12.

Do you get the value of the component of the TDA2003 section? Or if the schematic is a bit different than the TDA2003 datasheet.
I know it's tricky, but you know... you are the only source. :wink:

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 09 Nov 2017, 23:41
by J0K3RX
pretty sure it's correct...

Re: Hotone Nano Legacy Amps - Heart Attack  [traced]

Posted: 10 Nov 2017, 19:18
by Ichabod_Crane
You're really great!

I added the components's name following the original schematic of the TDA2003 from the datasheet.

C6 is pretty large.

What about R0 and C0? Something concern the loop fx?

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 11 Nov 2017, 00:53
by J0K3RX
Yeah.. R0 and C0 are the only components in the fx loop that come into play when you go into the fx return to bypass the preamp... I can probably get a reading on C0 with my meter.. It's one of those super small surface mount caps so I figured I would trace it and then circle back and measure the cap... Then my lazy ass kicked in and I said fukit... lol. I will get it and i figured I might try to get the complete fx loop also.. Not to many parts so I should be able to get it. It's using a TLC2262 opamp and just a few other components..

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 11 Nov 2017, 02:27
by J0K3RX
Oh yeah, I almost forgot there is a protection diode on the power.. nothing special so it was omitted.. Actually, I just forgot about it.

I was looking at the new nano legacy amps and one thing really turned me off! Actually a few things bugged me like the stupid ass names they came up with for one but, I can let that slide... What I can't let slide is the youtube demos!!! I don't know who this cock washer is in the demos but, Hotone needs to pull those off of youtube and get somebody who can compliment and properly demo the product. It doesn't have to be Ola or Lasse everytime but this guy just makes me ill!!! He may not be the worst player in the world (damn close!) but his overall presence in the videos combined with his horrible playing makes me want to stage dive into my glass coffee table and lay there until I bleed out!!! Somebody please take the 7 string away from this douche lord and bludgeon him with it!!! :evil:

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 11 Nov 2017, 11:41
by phatt
J0K3RX wrote:pretty sure it's correct...
Err?? Unless I'm mistaken,,, the inputs are marked wrong way round. :scratch:
Phil.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 11 Nov 2017, 12:54
by J0K3RX
phatt wrote:
J0K3RX wrote:pretty sure it's correct...
Err?? Unless I'm mistaken,,, the inputs are marked wrong way round. :scratch:
Phil.
You're right.. I used diptrace and the 2003 was rectangular instead of the standard triangle so I used some other audio amp and didn't pay attention... Normally I hide the function and just show the pin number. Thanks for the correction!

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 12 Nov 2017, 18:22
by bmxguitarsbmx
Thanks for your hardwork J0k3RX! Which is better, the hotone or the AMT tubecake?

J0K3RX wrote:Oh yeah, I almost forgot there is a protection diode on the power..
A diode to protect the ic from C4 discharge when power is removed?

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 12 Nov 2017, 22:13
by J0K3RX
I don't have a tubecake but I have played through one and I wasn't overly impressed with it. It may have been the cab that the dude was running into but it sounded muffled and didn't get very loud... The hotone sounds killer running into my 2x12 with Celestion greenbacks!

The diode is in series with the +18V right after the power switch. It's smd and I haven't looked at the markings on it yet but probably a schottky my guess..

@Mr.Crane - since you have this built can you at least tell us how it sounds using the schematic/values I provided? An audio demo would be even better but I will settle for a yay or nay...

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 13 Nov 2017, 08:29
by Ichabod_Crane
I was a bit busy. I still have my original board.
The difference with my board and the Heart Attack are:

C6
Mine: 2200uF
HA: 4700uF

Cx
Mine: 39nF
HA: 4.7nF

Rx
Mine: 39R
Ha: 220R

R2
Mine: 2.2R
HA: 12R

This is the "instruction" on the datasheet:

Cx
Purpose: Upper frequency cutoff
Larger than recommended value: Lower bandwith
Smaller than recommended value: Larger bandwith

Rx
Recommended value: ≅ 20 R2
Purpose: Upper frequency cutoff
Larger than recommended value: Poor high frequency attenuation
Smaller than recommended value: Danger of oscillation

R2
Purpose: Setting of gain and SVR
Larger than recommended value: Degradation of SVR
Smaller than recommended value: ---

About some of these parts I'm not sure what exactly they do at the sound.
Anyway, I have to try a psu at 19v (laptop), but now at 12v I get distortion when the volume pot is over the halfway.
Could those mods to be the reason to make the Hotone Nano Legacy sound "cleaner"? Or even them are not?
I need a transparent master volume for my amp model. (Of course it will have preamps in front).

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 13 Nov 2017, 12:17
by deltafred
J0K3RX wrote:What I can't let slide is the youtube demos!!! I don't know who this cock washer is in the demos but, Hotone needs to pull those off of youtube and get somebody who can compliment and properly demo the product. It doesn't have to be Ola or Lasse everytime but this guy just makes me ill!!! He may not be the worst player in the world (damn close!) but his overall presence in the videos combined with his horrible playing makes me want to stage dive into my glass coffee table and lay there until I bleed out!!! Somebody please take the 7 string away from this douche lord and bludgeon him with it!!! :evil:
I'm sort of getting the impression you are not keen on this guy's playing. :lol:

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 13 Nov 2017, 21:31
by Ichabod_Crane
Ichabod_Crane wrote: [...]
at 12v I get distortion when the volume pot is over the halfway.
[...]
Is C0 and R0 a way to reduce the input signal level and so the distortion? (But even the volume, I guess.)

I know the TDA2003 is not really fit to get the guitar signal: on the datasheet "Input saturation voltage: 300mV".
Nevertheless, the Hotone sounds really good. I can't understand.

Sorry, maybe I'm still not so good to read the datasheet. :slap:

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 13 Nov 2017, 22:13
by FiveseveN
Ichabod_Crane wrote: R2
Mine: 2.2R
HA: 12R
Well, you have 5 times more gain. Increase R2 to set the input sensitivity you require.
Also pins 1 and 2 are swapped (mislabeled) in J0K3RX's schematic.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 14 Nov 2017, 07:51
by Ichabod_Crane
Thank you very much!

With a larger R2 the risk is the degradation of SVR. I got it's something about the power supply, but what is the risk? Just to know it. :wink:

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 16 Nov 2017, 00:30
by bmxguitarsbmx
Ichabod_Crane wrote:Thank you very much!

With a larger R2 the risk is the degradation of SVR. I got it's something about the power supply, but what is the risk? Just to know it. :wink:
Increasing gain decreases the amplifiers ability to reject power supply noise. Check figure 13 in the datasheet.

Your power supply may not be noisy, or you could improve power supply regulation if you need more gain.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 16 Nov 2017, 08:33
by Ichabod_Crane
So it's ok to have R2 bigger, concerning the noise and the unwanted overdrive.

For the new schematic (the original Heart Attack) I have a 4700uF eventually, and 220R, too. But just 10R for R2. For testing I should try 10R + 2.2R. But I am busy in these days.

About my noisy PSU, it is 12v, and now I know I want absolutely a 18v. By the way, I need a good PSU 18v, at least 2A (my amp will have more thing than the Heart Attack). I'm looking for in the laptop PSU range, but I afraid of the switching noise o kind of. It is like a lottery!

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 16 Nov 2017, 11:12
by phatt
Hi Mr Crane,
You can get around Smode noise issues but requires filters on both the AC input as well as DC output,,and ideally all in a metal case.
Basically Smode psu's bleed noise back onto the mains as well as on the DC output and can be a real PITA.
As I found out when I plugged my Korg Keyboard into a very large wide bandwidth PA system which produced a high pitched whine out the Hi Freq horns. Buggered up my day I can tell you. :evil:
Some Smode supplies are not designed for audio (i.e. computer psu's) so you have to add filters.
Rather than me trying to explain how I got around the issue this chap worked out a solution.
http://ka7oei.blogspot.com.au/2014/08/c ... power.html
I used his idea to solve Smode noise on my diy guitar pedal board as well as my Korg Keyboard,, worked a treat. :thumbsup
Phil.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 16 Nov 2017, 12:02
by Ichabod_Crane
Good to know it, but honestly, I prefer work around this problem a little less, I can't spend too much money in this project, it's more than the simple mini amp as the Hotone. I'm trying to build a two channel preamp, buffer in front, a swapping before/after booster in the high gain channel, loop fx, and a remote footswitch (with relais) for clean/distortion channel and boost on/off.
I'm working in an amateur way, I still not so expert and this is my biggest project ever.
The best thing would find a good and ready psu. Though I know it could be hard, too. Do somebody know this? https://www.thomann.de/it/rockpower_pow ... _19_eu.htm

Thanks a lot, anyway! :)