Note:
I don't think I've ever seen a class-D amp implemented with anything other than MOSFETs...
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New ampeg speculation - A true B15 Reissue? part 2
- Thread starter john turner
- Start date
Note:
I don't think I've ever seen a class-D amp implemented with anything other than MOSFETs...
Ya see, this is where I get lost.
D-class, MOSFET, terms I've heard plenty of times, but I really don't know what they mean. Anyone care to give a quick and easy explanation as to what they mean to an old techno-illiterate bassist?
D-class, MOSFET, terms I've heard plenty of times, but I really don't know what they mean. Anyone care to give a quick and easy explanation as to what they mean to an old techno-illiterate bassist?
@aborgman: You must be right; You probably've never seen a class D amp with anything else but Mosfets, but there've been a few though.
From Wikipedia:
The main advantage of a class D amplifier is power efficiency. Because the output pulses have a fixed amplitude, the switching elements (usually MOSFETs, but valves and bipolar transistors were used) are switched either completely on or completely off, rather than operated in linear mode. A MOSFET operates with the lowest resistance when fully-on and thus has the lowest power dissipation when in that condition, except when fully off. When operated in a linear mode the MOSFET has variable amounts of resistance that vary linearly with the input voltage and the resistance is something other than the minimum possible, therefore more electrical energy is dissipated as heat. Compared to class A/B operation, class D's lower losses permit the use of a smaller heat sink for the MOSFETS while also reducing the amount of AC power supply power required. Thus, class D amplifiers do not need as large or as heavy power supply transformers or heatsinks, so they are smaller and more compact in size than an equivalent class AB amplifier.
From Wikipedia:
The main advantage of a class D amplifier is power efficiency. Because the output pulses have a fixed amplitude, the switching elements (usually MOSFETs, but valves and bipolar transistors were used) are switched either completely on or completely off, rather than operated in linear mode. A MOSFET operates with the lowest resistance when fully-on and thus has the lowest power dissipation when in that condition, except when fully off. When operated in a linear mode the MOSFET has variable amounts of resistance that vary linearly with the input voltage and the resistance is something other than the minimum possible, therefore more electrical energy is dissipated as heat. Compared to class A/B operation, class D's lower losses permit the use of a smaller heat sink for the MOSFETS while also reducing the amount of AC power supply power required. Thus, class D amplifiers do not need as large or as heavy power supply transformers or heatsinks, so they are smaller and more compact in size than an equivalent class AB amplifier.
Congratulations Ampeg, you have done it again! I've been grumbling for quite awhile now that I need a smaller amp for smaller gigs (something that can run either 4 or 8 ohms). My beloved SVT-CL and 410HLF is just WAY too much for small gigs...but I haven't found anything that I liked sound-wise that was small enough to easily lug around and match with a simple, single 8ohm cab, but still powerful enough to be a 4ohm backup for my SVT-CL. I was just about to buy a Genz Benz shuttle (which I'm not at all in love with tone-wise) when I saw the FB post about these amps... I can't wait until March to try it out! I have a feeling it will be WELL worth the wait! I'm really excited now! Thank you!
I really hope that Ampeg didn't go and design a class-d power amp.
They should buy the modules from a major manufacturer, but for these prices I don't think it's going to be B&O
Yes - Ampeg should design and build the pre-amps - that's where the tone comes in.
They should buy the modules from a major manufacturer, but for these prices I don't think it's going to be B&O
Yes - Ampeg should design and build the pre-amps - that's where the tone comes in.
+1, ready and waiting. Guess you and I will be doing reviews for everyone! hehehe
Wish it was sooner of course, but I guess that'll make a nice birthday present to myself!!!
heheheWill they go up for preorder? Also, any word on how readily available they'll be when they DO release? I assume they won't be as limited as the Heritage B-15, right?
5sg.
Yep, seems to be the best in order of need for power and the smaller heat sink for the Mosfets, thus keeping the whole package smaller.
+1, ready and waiting. Guess you and I will be doing reviews for everyone! hehehe
Wish it was sooner of course, but I guess that'll make a nice birthday present to myself!!!
Will they go up for preorder? Also, any word on how readily available they'll be when they DO release? I assume they won't be as limited as the Heritage B-15, right?
5sg.
I would assume that any reputable dealer would be able to offer a pre-order. These are going to be in large-scale production. Everyone who wants one should be able to get one.
AmpegUSA said:
Good answer!
Now... I don't really need to know when, but... just tell me that at some point you guys are going to make some form of all tube head for these new Portaflexes.
*shrug* Had to try.
lol5sg.
One thing that I'm finding frustrating,,,
Combining this exclusive and high price ticket and not disclosing a clear price,,meaning expected street is really sticking it to the "might be able to justify and swing it guys"
IE if lets say there is a group of people who say to them selves Ok if this was 2000 (street) I 'd buy it... If it was in fact 2800$ they might "justify" over a bit pondering and scrimping. If it was say 3500 and they still chose justified and scrimped it would take them longer to scrimp up that scratch. Combining no dis-closer on price with limited numbers means that once they find out that price,, the amount of time before the run sells out is less inspiring to make that effort.
But the truly wealthy waits and throws down the cash as needed,,timing wise.
Hope that made sense in written form.
Aj
Combining this exclusive and high price ticket and not disclosing a clear price,,meaning expected street is really sticking it to the "might be able to justify and swing it guys"
IE if lets say there is a group of people who say to them selves Ok if this was 2000 (street) I 'd buy it... If it was in fact 2800$ they might "justify" over a bit pondering and scrimping. If it was say 3500 and they still chose justified and scrimped it would take them longer to scrimp up that scratch. Combining no dis-closer on price with limited numbers means that once they find out that price,, the amount of time before the run sells out is less inspiring to make that effort.
But the truly wealthy waits and throws down the cash as needed,,timing wise.
Hope that made sense in written form.
Aj
Custom amp builder in Michigan... That sounds like it could possibly be Bruce Egnater (although he's most known for guitar amps, not bass amps). Does anyone know?
Also, if those prices posted earlier in this thread are anywhere close to being right for the heads, I'm in for a 500 Watt version! ESPECIALLY if it sounds as good as the Micro VR heads.
- Jun 25, 2006
- 3,226
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- Disclosures
- Owner, Pike Amplification & 3Leaf Audio
It was mentioned in the last thread that they're being built by George Metropoulos of MetroAmp.
So I was at the Ampeg display at NAMM today looking at these new Heritage B-15s when up comes Jess Oliver -- the guy who invented them! A few guys demo'd one for him and he seemed to enjoy seeing his legacy continue. There were some cameras and video so maybe it will pop up on youtube, but it was cool seeing Jess.
