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Blackstar HT-5 Schematic?


ehedwr

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I think they're keeping the schematic secret so that people won't figure out that it's actually a hybrid solid state/tube amp and not all tube. Not that there's anything wrong with that. The amp sounds great. It's just that you can charge more for an amp if people think it's "all-tube"

 

My guess is that it probably has a solid state phase inverter and most certainly uses solid state rectification. There's also probably some op amp chips along the signal path boosting and shaping things too.

 

I own this amp and love the high gain sounds. Makes way more sense to me compared to buying an expensive all-tube amp for the home and using an expensive attenuator with it to get the same sound (maybe worse) at home where the amp is getting use 90% of the time. Cheaper maintenance too. Just don't plan on modding one when you get it more than swapping out tubes. It's ain't that kind of amp.

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Judging by the gut shots, the phase inverter is indeed SS. If the design is anything like in HT series of pedals (like they claim it is) there's actually quite a lot of solid-state amplification and signal shaping in there. If you ever seen insides of this thing it's pretty evident. There is also a solid-state diode soft clipping gain stage on each channel preceding the tube gain stage(s). Cab sim is a bunch of solid-state active filtering circuits too. etc.

 

I think they didn't have to use switched mode power supply in this one like they did in the HT pedals. Looks like an ordinary linear supply.

 

I can make a schematic out of this thing if people can provide me high quality, detailed gut shots of both sides of the PC boards (something from which I can see component values and see the PCB traces) as well as some overall shots of the internal wiring to tube sockets and switches.

 

Also, if you are swift enough to work on PC-boarded amps you can mod this thing like any other solid-state amp. Modding has never been exclusive to all-tube amps. The mods may not be similar as in tube amps (e.g. change cathody bypass cap) but they are perfectly sensible for anyone familiar with basic OpAmp and analog circuits.

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Judging by the gut shots, the phase inverter is indeed SS. If the design is anything like in HT series of pedals (like they claim it is) there's actually quite a lot of solid-state amplification and signal shaping in there. If you ever seen insides of this thing it's pretty evident. There is also a solid-state diode soft clipping gain stage on each channel preceding the tube gain stage(s). Cab sim is a bunch of solid-state active filtering circuits too. etc.


I think they didn't have to use switched mode power supply in this one like they did in the HT pedals. Looks like an ordinary linear supply.


I can make a schematic out of this thing if people can provide me high quality, detailed gut shots of both sides of the PC boards (something from which I can see component values and see the PCB traces) as well as some overall shots of the internal wiring to tube sockets and switches.


Also, if you are swift enough to work on PC-boarded amps you can mod this thing like any other solid-state amp. Modding has never been exclusive to all-tube amps. The mods may not be similar as in tube amps (e.g. change cathody bypass cap) but they are perfectly sensible for anyone familiar with basic OpAmp and analog circuits.

 

 

 

Yea it's just out of my league. Not just the problem of dealing with traces and PC boards...but the whole theory as to how you would mod it without a schematic. I think it sounds fantastic as it is as far as the voicing goes and I really can't think of a way to improve on the sound for what it is anyway.

 

My experience in modding amps is basically dealing with simple Fender amp circuits. Modifying the tone stack caps, changing the cathode bypass caps and resistors, treble bypass cap modding the controls, altering the negative feedback loop, altering the input resistor values, swapping out tubes and speakers, maybe substituting the rectifier for solid state, maybe also just following mod suggestions people have posted online or buying "mod kits" and trying them in amps I own.

 

I have an awesome sounding tweed Champ clone that I modded heavily. It actually has fantastic clean sounds now. I achieved it by trial and error modifying the cathode bypass caps and resistors at every gain stage and at the power tube, using a bypass cap at the volume pot, changing the input resistor at input 1, disconnecting the negative feedback loop, swapping out the speaker for 10" Weber. It's a one-of-a-kind amp now. Instead of just being a one-trick-pony that only sounds good with the volume on 12, it has great tone everywhere and goes from wonderful cleans to great overdrive. Takes pedals great too.

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I don't get what those zener diodes are doing. I don't think they're for clipping. Think any of these are for clipping ?

 

 

The Zener diodes are indeed for clipping but only for the sake of protection, limiting the input signal below their zener voltager so that, for example, static voltage spikes can

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hi friends, i need help to find a diagram or schematic (circuits, etc,) of a 50 ht club blackstar head, or similar. i need to fix this amp, and put in a tung sol tubes. if black satr dont suply that schematc what can i do???. i buy in e bay this amp in november or dicember last year. the problem begins with a strange noise and also the am start to get very hot, then one day when a turn on the amp just doesnt do a sound, now when a change tubes the sound was very intermitent no hig volume. i need to fiz this but the only thing i need to find is the diagra, or schematic. i dont know, what can i do here?? im in sonora mexico. where i can fix this think. thanks for your atention friends.

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