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Hotone Heart Attack

Posted: 23 Feb 2016, 20:39
by J0K3RX
WTF is inside these little Legacy Nano amps? I will buy the heart attack since they are so damn cheap! $139 and it comes with an 18v power adapter! I hope it's traceable and not all cock blocked!! Really want to see what the power amp section is utilizing and of course the preamp section is killer sounding... It says all solid state transistor based but that could be all sorts of weird shit...





I actually like the sound of the heart attack better than the Mesa!

Hotone Nano Legacy Amps - Heart Attack

Posted: 27 Feb 2016, 18:11
by J0K3RX
I have one ordered, should be here in a couple days. In the meantime I found these pics on the web, looks somewhat promising other than the fact that they have sanded off the tops of the IC's.. The power amp section shouldn't be too hard to figure out.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 27 Feb 2016, 20:52
by karul
J0K3RX wrote:The power amp section shouldn't be too hard to figure out.
It's a five legged chipamp, probably TDA2003, if not, then TDA2030, TDA1875, or something similar.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 02 Mar 2016, 05:48
by J0K3RX
karul, yeah I spotted that 5 pin chip amp right away... Should have some answers, as soon I get my hands on that dirty little Ho :twisted: I ordered one from SamAss.com and they promptly charged my card then canceled the order 2 days later for some shit about my billing and mailing address (which are identical). The damn charge is still pending on my acct and I am pissed! In any case I ordered another one from prymaxe.com today and they shipped it right out, 2nd day priority mail, got a tracking# and delivery date of Thursday. Never did like SamAss anyway...

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 03 Mar 2016, 20:31
by J0K3RX
karul wrote:
J0K3RX wrote:The power amp section shouldn't be too hard to figure out.
It's a five legged chipamp, probably TDA2003, if not, then TDA2030, TDA1875, or something similar.
Yup... You guessed it right on your first guess, it's a TDA2003. :wink:

I knew this thing was small but it's even smaller than I thought!! The knobs are so small they are like aspirin tablets.. :D

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 04 Mar 2016, 09:08
by J0K3RX
Alrighty then... Sorta good news, the IC's in the one I got have not been sanded :thumbsup There are 4 of the JRC4580's and one TLC2262. There is a 78L09 voltage regulator and of course the TDA2003. There are 5 other transistors all SMD and a combination of through hole and SMD resistors and caps... The input jack is totally shielded which is a good idea on this thing cause the gain is through the roof but, it's very noise free.. Guess that shield does it's job. I will start getting the values of all the parts soon and then start connecting the dots. This thing is totally traceable.. :wink: I will tare this thing down to the bone if needed. :twisted: I already know I am gonna have to remove the SMD cap to get a good read on them. Probably remove the jacks also for better access.. Hi-Res pics will follow.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 09 Mar 2016, 14:26
by marmaliser
Can't wait to see this one. I have an early 80's Marshall lead 12 Stack that I think this would be cool in (make a new chassis for it whilst i refurbish the lead 12)
If i can be of any help just shout up. I can work my way round diptrace and don't mind ordering boards

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 09 Mar 2016, 18:05
by notnews32
J0K3RX wrote:Alrighty then... Sorta good news, the IC's in the one I got have not been sanded :thumbsup There are 4 of the JRC4580's and one TLC2262. There is a 78L09 voltage regulator and of course the TDA2003. There are 5 other transistors all SMD and a combination of through hole and SMD resistors and caps... The input jack is totally shielded which is a good idea on this thing cause the gain is through the roof but, it's very noise free.. Guess that shield does it's job. I will start getting the values of all the parts soon and then start connecting the dots. This thing is totally traceable.. :wink: I will tare this thing down to the bone if needed. :twisted: I already know I am gonna have to remove the SMD cap to get a good read on them. Probably remove the jacks also for better access.. Hi-Res pics will follow.
Awesome! I can't wait to see your pictures and your trace of the circuit. The demos of this little guy DO sound great.. I've been looking into building a small amp lately, something in the vein of the Superfly submini tube amp or the Ruby-Q (the ROG Ruby + Mr. EQ in one), something with lots of quality tonal capabilities in a small package. This Hotone Heart Attack sounds like it fits nicely into that category of small versatile amps for sure!

I'll be checking back often. Thanks again!

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 09 Mar 2016, 21:30
by J0K3RX
marmaliser wrote:Can't wait to see this one. I have an early 80's Marshall lead 12 Stack that I think this would be cool in (make a new chassis for it whilst i refurbish the lead 12)
If i can be of any help just shout up. I can work my way round diptrace and don't mind ordering boards
They were correct in using the word Nano! This little beast has some tiny ass EIA-96 resistors and I am having to use a jewlers glass to read them...
This little program is coming in handy for deciphering the value codes!
http://www.schematica.com/resistor_colo ... istor.html

There are a couple parts that I have not seen before :scratch: They look like little capacitors perhaps panasonic smd metal film capacitors but I am not sure..

they look alot like these but still don't know for sure.. Perhaps knowing where they fit in the circuit will give a better idea.
Image
notnews32 wrote: Awesome! I can't wait to see your pictures and your trace of the circuit. The demos of this little guy DO sound great.. I've been looking into building a small amp lately, something in the vein of the Superfly submini tube amp or the Ruby-Q (the ROG Ruby + Mr. EQ in one), something with lots of quality tonal capabilities in a small package. This Hotone Heart Attack sounds like it fits nicely into that category of small versatile amps for sure!

I'll be checking back often. Thanks again!
I think if a person were to sit in a room and do a blindfold test using this thing plugged into a 2 X 12 or 4 X 12 cab you would see some shocked faces when the blindfolds are removed! It really does get surprisingly loud and the tone is thick with a lot of low and mid range and the attack is sharp and precise! Flat out KILLS with a tube screamer in front of it!! :twisted:

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 10 Mar 2016, 14:20
by Frank_NH
Interesting thread. I see Hotone have a whole series of these miniamps. I'd be very interested in the British Invasion (here's a demo link):



Probably similar inside to the Heart Attack save for the preamp circuitry.

I have to agree - these units are REALLY small. I'd preferring building my own only because I could make the rig a little larger (certainly the knobs should be! :shock: ).

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 20 Mar 2016, 16:45
by J0K3RX
Sorry, haven't had time to start picking at this thing much yet. I did play around with it a couple times and I managed to run a few of my high gain jfet preamps through it and WOW! The Tight Metal and Tight Rock are the best in my opinion, probably better than the Nano/Rectifier circuit..

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 11 Apr 2016, 11:23
by 287m
hei J0K3RX

in search of TDA2030, i found this
[youtube][/youtube]

what you think?
source : http://www.paulinthelab.com/2012/05/tda ... board.html

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 25 Jun 2016, 14:52
by J0K3RX
Been a while... :roll: Had a lot of shit on my plate lately so, this had to take a back seat for a while. I have a shitty camera but I managed to get some pics, some are blurry and some are clear.. not all that great but, at least you can see what I am dealing with here.. To get this thing traced I am gonna have to remove some caps, the jacks, heatsink etc.. Shouldn't be a problem, I'm sure I can do it without inflicting damage to the board or parts...

https://www.dropbox.com/sh/a7x1w9q7bv50 ... QsGta?dl=0

I was thinking... :hmmm: If a person was to get 3 or 4 of these they could have a nice little 3 or 4 channel amp/preamp with some minor switching work. Maybe re-house them into a small head or rack. :scratch:

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 25 Jun 2016, 16:27
by Ice-9
I have the British invasion nano amp. You are right Jok3rx, they are tiny. Sounds great through my EVH 2x12 and quite loud for the output. I stuck one of my boosters in front of it for a good bit extra dist.

The British invasion is the AC30 model. 8)

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 16 Oct 2016, 13:29
by Ichabod_Crane
Hi guys. Waiting for some news about this amp. :)

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 04 Nov 2017, 10:29
by Ichabod_Crane
Bump!

I tried to build a power amp section with the TDA2003.

Image

Schematic come from here, I taken off the input stage.
http://www.redcircuits.com/Page145.htm
Just one mod. A 50k replace the 100k pot.

Powered with a 12v I got noise, but it could be the cheap PSU. Oscillation if I don't shield it. With a 9v battery I got mush less noise.
The speaker is a 8" - 8 Ohm - 15w.

The problem is that i got ditostrion too soon, already at half volume set. I expected it was clean.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 04 Nov 2017, 15:48
by J0K3RX
Best to follow the datasheet, a lot of info for design specs, test circuits, operating conditions, distortion vs. frequency, distortion vs. output power etc..

http://www.mouser.com/ds/2/389/stmicroe ... 206353.pdf

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 05 Nov 2017, 08:06
by Ichabod_Crane
Thanks, J0K3RX!

There's no suggestion about the pot to use, some schematic use 50k, or less, I don't know what it change the thing about distortion and volume. My TDA2003 is loud like a Noisy Cricket (LM386). No how I expected from a 5w. :roll:

The input cap should change just the noise at switch On/Off, reading the datasheet. Then, the value of the Cx is not really recommended, I guess, but I'll search anyway a 39nF. (What does mean: "Lower bandwidth", "Larger bandwidth")
My C12 (2200uF) in the original schematic is a 100uF, but even this is not really recommended. It should be a noise reduction trick, isn't it.

I think the mods I used aren't not so critically. Rather, maybe I can act on R1 220R in the original schematic. The datasheet says "Setting the gain", "Smaller - Increase of drain current". What does it mean? GGG, in its PCB show a second resistor of 470R to swap the 220R.

Listening other version of the Nano Legacy the amps seem very clean, and the volume not acts at all in the gain or distortion. See the Hotone Diamond. My version encrease the distortion at higher volume set.

Is there some chance to draw at least the power section of the Heart Attak?

:thumbsup

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 05 Nov 2017, 18:47
by J0K3RX
Yes, I actually have it all apart still and I was just looking at it about an hour ago. I will see if I can get that later today maybe tomorrow.

Re: Hotone Nano Legacy Amps - Heart Attack

Posted: 05 Nov 2017, 21:39
by Ichabod_Crane
Great! :wink:

Thanks.