Amp tinkerers and people who aren't afraid of 700 volts or so in here....

Moderators: Slowy, Capt. Black

#855801
Hi guys!
My first post, not a native speaker, be kind =)

I was wondering why so many manufacturers are using class D amps in bass amplifiers these days.
It turns out that one of the main suppliers for Fender, GK is the Danish company ICEPOWER (Bang and Olufsen branch).
They make fantastic ICEpower50ASX2(SE) modules you can find on Aliexpress (visually the same) for 100 NZD: power supply included, no radiator, wow.

I had Warwick Pro Tube IV 400-Watt bass amp to compare. 1x15+2x10 cabs. TUNE active 4 str bass (fast asf).
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I wired ICEpower50ASX2(SE) as BTL module for the bass preamp with a relay and shove it into the used rack unit.
The simple tube Alembic preamp (with my favourites 6SL7) +icepower totally blew away fancy German manufacturer. Wow.
It's like a 10 times lighter and does not heat up.
Moreover, this 170W module was actually LOUDER than 400W Warwick. I think this is due to nice breakup of icepower.
In any case, it was more than enough for a loud drummer.
I added two 5v fans because it fell into protection mode due to overheating during a long and loud rehearsal, now it's cold as a corpse.


After that I added dirty channel based on Diezel VH4 circuit (to compare it with my tube head).
And blended them together, damn that's a bomb!

I'm still trying new things in the scheme(out of curiosity, I just can't stop) but at this point I am completely satisfied.

I also use this amp for my Hi-Fi system (with the tube preamp switched off and switched to SE mode, 2x50W).

I compared the dirty channel with the same in my tube head, and the tube poweramp sounds much sweeter but softer at the bottom. I prefer it for the guitar 100% but I'm sure Blackstar and others experienced companies can handle it.

If you have a modern class D bass amp in Christchurch I'm looking forward to compare them.

NOTE, the circuit is messy and still under construction.

I wrote this post to encourage anyone who wants to try it.
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#855938
weight is the important thing here, having hefted the vibroverb around with chassis and speaker.... I'm lucky I didn't get a hernia.
#856064
Daniel_T wrote:Thanks, guys. Appreciate it.
The first time it was like


Mk1, in about 30 years time people will be wanting it so badly :lol:
#856150
Bg wrote:Mk1, in about 30 years time people will be wanting it so badly :lol:

In 30 years they will stare at it as at dinosaurs shit! Smart watches will be able to mock mesa, mind my word.

Kris wrote:did i read the spec sheet right that these can be run @170w mono/4 ohm?its probably well above my skill set but ive been thinking of grabbing one or more of something like this for ages.


Yes, 170W at 1%THD, but it's 220W at 10%THD! Breakup is really pleasant so I'm not sure what THD I reach at the rehearsal. It can be 50% and nobody will know =)

This module is plug-n-play with heaps of protection, don't worry.
I blew it already, haha, the input stage has dissapeared in the blue smoke. Chinese speaker connectors colors were not matching the module +/-. So I shortened the output to the ground. Stupid mistake but it was easy to fix.
Come on in.
#856152
Daniel_T wrote:
Bg wrote:Mk1, in about 30 years time people will be wanting it so badly :lol:

In 30 years they will stare at it as at dinosaurs shit! Smart watches will be able to mock mesa, mind my word.

Kris wrote:did i read the spec sheet right that these can be run @170w mono/4 ohm?its probably well above my skill set but ive been thinking of grabbing one or more of something like this for ages.


Yes, 170W at 1%THD, but it's 220W at 10%THD! Breakup is really pleasant so I'm not sure what THD I reach at the rehearsal. It can be 50% and nobody will know =)

This module is plug-n-play with heaps of protection, don't worry.
I blew it already, haha, the input stage has dissapeared in the blue smoke. Chinese speaker connectors colors were not matching the module +/-. So I shortened the output to the ground. Stupid mistake but it was easy to fix.
Come on in.

doesnt happen with olde fenders and Marshall, keep it just in case! look at the teary eyed people here who get emotional over old bottle based amps ;)
#856181
What?! Gearfest?! And anyone can play anything?
That's awesome!
My second tube head is stuck in Europe :(
And this amp should be remade.
But I have curious experience with different tubes to share
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