high power, class a/b and, heavy metal - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 9th April 2005, 07:12 AM   #1
RogerG is offline RogerG  United States
diyAudio Member
 
Join Date: Apr 2005
Location: Atl, Ga
Default high power, class a/b and, heavy metal

My first post about a high power mono block went well. Thanks to all. It did help. But I have to ask a few more questions.
I know that 500wrms@8ohms is a load of power. But it's done everyday by many. My moto is, If it's man made, this man can learn to do it!
Some local hifi techs that I know suggest taking a working amp design, maybe 300w/8ohms and altering it for the power I'm looking for. The names Marshall and Peavey have come up.
This seems like a good idea to me. If I know anything here it's that I don't know enough to start from scratch. But reengineering a working design has got to be tricky.
Also, I'm trying to figure in to all this that I listen to heavy metal. The music is distorted, low frequency and, should be played loud!

Do any of you think it's better to mod a working design?
Does the circuitry class matter?
If so, why?
Does my choice in music affect the design?
Any info helps, so please share it with me.
Roger
__________________
It's only dumb if you don't ask!
  Reply With Quote
Old 9th April 2005, 07:44 PM   #2
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
go classAB, some others might recommend the new classes for a bass driver.
Do not consider ClassA- too hot and at your voltages you must keep the output cool so you cannot go Hi Bias either.
The SOA of the output is seriously affected by transistor case temperature forcing ultra heatsinks into your design. Probably fan cooled, the fan noise might not be a problem after a couple of nights. You will have gone deaf by then.
good luck
__________________
regards Andrew T.
  Reply With Quote
Old 9th April 2005, 07:55 PM   #3
diyAudio Member
 
Join Date: Dec 2003
Location: Munich
Hi Roger!

I guess that in most comercial designs you would need to change the
power supply..... transistors with required voltage rating (input and VAS) and higher voltage rating + power in the output stage....
power... adjust all bias settings accordingly....
...adjust frequency compensation....

One convinient point:
You can use the mechanical set up and may be some protections as
delayed speakers relay ....

But by the way: For your ears the difference between 300W and
500W is just a small step. Just 2.2 dB. Not worth much efforts!!

But you could pick a working amp which delivers 2 x 300W into 4 Ohms and bridge it to a mono 600W/8Ohm mono block...

My
....be careful, you might loose some fun after hammering your ears to deafness....

By Markus
  Reply With Quote
Old 9th April 2005, 08:00 PM   #4
diyAudio Member
 
Join Date: Dec 2003
Location: Munich
@Andrew:
... I see you had the same concerns about Roger's health...
...overlapping answers...
  Reply With Quote
Old 10th April 2005, 02:22 AM   #5
RogerG is offline RogerG  United States
diyAudio Member
 
Join Date: Apr 2005
Location: Atl, Ga
Quote:
Originally posted by ChocoHolic
@Andrew:
... I see you had the same concerns about Roger's health...
...overlapping answers...
Thanks for the health advise, guys. Do you handle bad backs, too? Obviously kidding!
Really, the input is great. A/B class did seem to have advantages. Less heat being one of them.
I posted about this when I first joined the site. For ideas on what it take to do it. I know that 300w will be nearly as loud as 500w. And I'm kicking around another suggestion that I go with 400w/8ohms. I'm just trying to match my driver ratings as close as I can.
I am worried about my choice in music. I need an amp I can lean on pretty hard without hurting it. But it must be able to reproduce what I put into it. Which will be very heavy and distorted anyway. Will my love for metal make an amp design impossible?

Roger
__________________
It's only dumb if you don't ask!
  Reply With Quote
Old 10th April 2005, 02:38 AM   #6
diyAudio Member
 
Join Date: Jun 2004
Location: Knoxville
I would think that you might need some headroom with that type of music. I would suspect also a faster slew rate would help keep up with the harmonics (or distortion)generated in Metal music. This distortion is specific and can be easily "distorted". Faster slew would certainly keep up with the high freq.'s better. Too much freq. compensation and it may sound muddy.

I would buy an amp that will not blow the speaker drivers, i e rated less. Speaker diaphrams don't move linear after about 60% anyway. Might even under-rate the speakers a little for these tunes.

Avid Tool listener...

Chris
  Reply With Quote
Old 10th April 2005, 03:01 AM   #7
RogerG is offline RogerG  United States
diyAudio Member
 
Join Date: Apr 2005
Location: Atl, Ga
Quote:
Originally posted by cunningham


Avid Tool listener...

Chris
Thanks Chris! BTW check out At Gun Point from Chattanooga. Great local metal act and very cool guys.
Roger
__________________
It's only dumb if you don't ask!
  Reply With Quote
Old 10th April 2005, 11:24 AM   #8
diyAudio Member
 
darkfenriz's Avatar
 
Join Date: Jun 2004
Location: Warsaw
in HM you have plenty of distortion of guitars, sometimes bass and even vocals and it can 'mask' the distortion of your amp at cliping level. Remember to use speakers with high-power tweeter to avoid distortion-induced breakdown. Sorry for hurting language.
  Reply With Quote
Old 10th April 2005, 12:10 PM   #9
diyAudio Member
 
demogorgon's Avatar
 
Join Date: Jul 2004
Location: Behind you.
Send a message via MSN to demogorgon
hmm, your imense power requiremets got me thinking, Mr.Elliot has some nice projects out on his page, this being a 500W sub amp, but there is nothing that keeps you from using this as a fullrange amp..

http://www.sound.westhost.com/project68.htm

the output devices used are fairly fast devices from on semi, i see no reason for this amp not to have a decent slew rate..

it may be a possibility?

-marius

(immortal - Wrath from Above)
Metal Roxx
  Reply With Quote
Old 10th April 2005, 01:03 PM   #10
diyAudio Member
 
Join Date: Jan 2005
Location: Østfold
What about a good tube amp?

Tubeamps sounds absolutely fantastic on heavy metal.

Regards,
Peter
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Heavy Metal berkshirejd Music 65 4th February 2011 06:55 PM
So what's Your Heavy Metal name? pinkmouse The Lounge 18 20th June 2006 08:38 PM
heavy metal, low power guitar amp? inforce Tubes / Valves 13 26th October 2004 03:17 PM


New To Site? Need Help?

All times are GMT. The time now is 02:36 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2