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February 06, 2023, 07:02:02 AM

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#1
Guitar News / Blackstar AMPED 2 - Pedalboard...
Last post by joecool85 - February 01, 2023, 06:42:14 PM
Less than 6 months after releasing the AMPED 1, Blackstar has released the AMPED 2.  Like it's predecessor, the AMPED 2 features a 100w power amp to drive your speaker cab loud enough for gigging.  You can flip the attenuator switch and bring things down to bedroom level with ease though, which is quite fantastic.

Honestly, the sounds are pretty impressive.  The price is either a bargain or a total ripoff, depending on which side of the aisle you stand on.  Current MSRP is $649 USD.

PMTVUK does a great rundown: https://www.youtube.com/watch?v=l20VTiROkFA

MusicRadar release article: https://www.musicradar.com/news/blackstar-dept-10-amped-2-pedal-amp-multi-effects
#2
The Newcomer's Forum / Re: Shorted IEC line filter
Last post by mandu - January 28, 2023, 06:40:50 AM
These line filters live for many years.
Probably, the ac supply voltage exceeded more than the rating of some component for too long.

Regards.
#3
Amplifier Discussion / Re: 12w Marshall
Last post by phatt - January 27, 2023, 07:23:46 AM
Quote from here;
https://www.soundonsound.com/techniques/what-class-d-amplification

Under, The limitations of Class D
(near the bottom of page)

"Thirdly — not finally, but enough for now — a Class-D amplifier has a **relatively poor damping factor.** The damping factor is the ratio of the impedance of the loudspeaker to the output impedance of the amplifier (it's a little more complex than that, but let's not get bogged down with details). In simple terms, it's a measure of how well the amplifier can control the movement of the diaphragm of the loudspeaker. A good amplifier doesn't just give it a push and hope for the best; it senses where the diaphragm is from moment to moment and controls its position. To do that, a high damping factor is desirable, and, as mentioned above, a simple Class-D amplifier has a low damping factor."

I think of this much like a Valve Amp where the same power output is delivered to  4,8 or 16 ohm speakers partly because most Valve amps have *Low damping factor*.

So even if you drive an 8 ohm speaker from the 4 ohm tap the power is much the same but freq suffers a little.

Better minds may explain this better but there is obviously a connection.
Phil.
#4
Amplifier Discussion / Re: 12w Marshall
Last post by guzzis3 - January 26, 2023, 07:02:30 PM
Thank you phatt. Does this trickery explain why it's as loud into 16 ohms as 8 ? I just assumed that as you loaded the outpput of the transistors it's decrease power ?

I wasn't interested in distortion, I just wanted something for practise. If I wanted singing distortion in a SS amp I'd build a Lead 12. (see what I did there?)

Hotone have built a floor mount amp with 2 of the models built in. The one I would buy is the Britwind which combines a plexi and AC30 in a 70W package, but they are far too expensive for what they are..

https://www.ebay.com.au/itm/234080413858?epid=3049063806&hash=item368047a8a2:g:nTkAAOSw1T1cAAcz&amdata=enc%3AAQAHAAAAoDwDsL5qWEAqWy%2BJFDrTazBfqLcnXCktk7k87uz%2F9%2BJbxkVpC0AAWRsGFyqkVRuk217VbCghjYJx3D6PJnC%2FNGj%2FK0rzT6OaziCXKqVpurB7aMFa4r4K9vL%2BTe5nXWDvpv4rL2v%2FwEn1uDpgaD8KEiRj%2B1Lpvyb%2FAXgcGmAJcIadN1ETjwXdkk3xshg1%2Ba4kdV2iKERXGTQJ2CX96CN494c%3D%7Ctkp%3ABk9SR9Crroi-YQ

As I say I can knock together a valve amp in some hours mostly from stuff I have laying around, but that was never the problem I was trying to solve.

Anyway have fun!
#5
Amplifier Discussion / Re: Add effect loop to jc120
Last post by joecool85 - January 26, 2023, 10:19:48 AM
Quote from: Tassieviking on January 21, 2023, 09:52:50 PMPhil, unfortunately Enzo passed away in August last year.

https://music-electronics-forum.com/forum/music-electronics/967156-rip-enzo

Thank you for sharing this, I had no idea.  Enzo will be missed across many forums - he was a gem of a man.
#6
Amplifier Discussion / Re: 12w Marshall
Last post by joecool85 - January 26, 2023, 10:14:17 AM
I don't mind as long as the topic goes back to the original - I'm very excited about this 12w Marshall!

The Hotone Nano's sound neat, but I also have only heard them on the Tube.  Any time more good-sounding SS gear is out there, it's a good thing.  It gets people to play, and with modern gear.
#7
Guitar News / Re: Boss releases updates to K...
Last post by joecool85 - January 26, 2023, 10:06:44 AM
Quote from: phatt on January 23, 2023, 06:27:23 AMI've heard these at gigs and not so impressed,, very sharp and too much bandwidth to really nail the classic sounds but the young ones seem to like this stuff.
I guess I'm showing my age here  ;)
I have noticed a lot of these Kats come up for sale on gumtree in my part of the world,, humm which suggests to me that they sell on novelty which wares off in a short time.
Phil.

This is my take on it as well, but who am I to argue with the masses?  As far as new gear goes that I want to try, Orange Super Crush 100 is at the top of my list!
#8
Amplifier Discussion / Re: 12w Marshall
Last post by phatt - January 26, 2023, 06:29:02 AM
In answer to Guzzis3 previous Q, Class D  are a switching amplifiers which use a Pulse Width Modulation system.
 They switch so fast that very little heat is generated thanks to mosfet teck, so no need for big heat sinks. 

C0mplikated to ezplain but some info here might help;
https://www.howtogeek.com/792135/what-is-a-class-d-amplifier-and-what-are-they-useful-for/

The Hotone circuit tricks, after a little bit of analog at input the rest is most likely all done in the digital realm using IR's  (Google *Impulse Response* for clues on that)
Hence each one is programed with a different flavor. ALL the shape and grit is done in the digital chip while the D class output would run clean.

The one I liked most was the "Mojo Diamond" gives a good balance between clean and drive but I've only heard them on the tube.
I'd be waiting till they realise they can make a unit with 4 or more different modes in the one unit but the Diamond would work well with my existing pedal setup.
hope that helps, Phil.
#9
Amplifier Discussion / Re: 12w Marshall
Last post by Tassieviking - January 24, 2023, 12:17:06 PM
Guzzies3, have you considered trying to build some of BajaMans Pre-Amp pedals from https://www.freestompboxes.org ?
Some of those can work well in front of an amp I believe.
He has made Amp sims for several different amps as well as speaker sims etc.
They all have vero board layouts for them.
I made up some of them as PCB's but I havent had time to make any yet.

As far as hijacking a thread goes, I don't think Joecool85 minds it happening, at least I hope he doesn't.
As long as it is in a friendly manner and it keeps this site as a friendly forum where like-minded people can have a chat and share ideas and stuff.

Michael


#10
Amplifier Discussion / Re: 12w Marshall
Last post by guzzis3 - January 23, 2023, 07:50:19 PM
Ebay. The seller is in Australia and the power supply is correct. It's very clean, no distortion at all but I think it must have some shape to the response curve, probably drop off at low and high like a valve amp. $71 and some cents.

Getting into ambiguous terms. I don't have a spectrum analyzer so I can't be precise, but it sounds a bit warm or creamy or something, not cold and precise like say a hifi amp with the impedance fixed to accept a guitar in. By comparison the 2 valvestates and the vox pathfinder sounded "glassy" clean with a lot of top end. I usually like bright amps but they are just too much. It doesn't help that I don't understand the knobs..

https://www.ebay.com.au/itm/354057429136?epid=11018833546&hash=item526f77a090:g:egsAAOSwBetduoCR&amdata=enc%3AAQAHAAAA4HKJlVQx7uUaNQIt8AGhA7TBtNdUv29YBnUT9FCBwOVqBppfGQy5AjCNyFU3tVj5WSZIjNTOvKjRG16ctokT6mXr2G6JJYqrPMrm%2BjxLhitv0gmNxP9c9s40xNj9v8M7R14Q%2BFIL3zgdtiZ57NQJOHf%2BNzP3%2FkbFtzOdQ5RGinp69nIe4DA4uxUc%2F2ObpdIW3W7KCGtpwrtdOaHSXWN9w5e4XNt3KPCneqVlmbxPb2%2BpfH6OibzvQ9wMxMTQt%2Fbri7su7LyhJfiY48p0wPAGRpTMaOifYe9K18VqcRU3duHA%7Ctkp%3ABFBM8I3Lk7xh

There are lots of clips on ewtube but they seem to exaggerate the distortion. For want of a better reference it sounds like a really nice fender clean.

Well if we are drifting off topic I have a question if I may. The amp says "class D". I don't know what that means. Normally a SS amp is less loud into 16 ohms than 8 then 4. This seems not to be the case. I am running it into a 4x12 (8 ohms) wired as 2x2x12 at 16 ohms. Plug in one and flat out it's about right for practice. Plug in both pairs in parallel it should be seeing 8 ohms but there is no discernible increase in volume. I don't understand this. The speakers are chinese celestions.

As I say I've a second coming. With the GT8 and the 2x2x12 it should give some pleasant stereo chorus etc sounds if I want to play with that.