Amp/Preamp Asylum

RE: Nor did we need them to know the difference between passive and active nt

69.118.107.235

Leo loves music

In Reply to: RE: Nor did we need them to know the difference between passive and active nt posted by Ralph on November 08, 2024 at 09:15:36

Usually a preamp with no gain is considered as passive. But this one is special. It has active circuits inside.
In 1991, Motorola rocked.

Edits: 11/08/24

Follow Ups:

Sure, we do. - Kal Rubinson 10:02:23 11/08/24 (5)
A passive component is, simply, one that does not require an external power source in order to function. A transformer is a passive device even though it can provide a voltage gain (albeit cost of current).
- RE: a power supply for motorized potentiometer - Leo loves music 10:24:03 11/08/24 (2)
  w/o any circuit, you call it active or passive.
  Please do not fussy about words. It is meaningless.
  
  Edits: 11/08/24
  - Words have a lot of meaning, just to be clear. - Ralph 10:48:26 11/08/24 (1)
    Let's take the example of what happens if the power supply is disconnected.
    
    If a motorized pot it will still play. An actual active circuit such as the one that is the subject of this thread will not.
    
    Kapish?
    - RE: agree - Leo loves music 10:52:11 11/08/24 (0)
      Words have a lot of meaning. You can build everything on words including bankrupt.
- RE: thank you for education - Leo loves music 10:14:27 11/08/24 (1)
  The whole point of this thread is BUF03 not the passive.
  
  There are many companies went to bankrupt because they voted the wrong CEO.
  - Huh? - Ralph 10:46:31 11/08/24 (0)
    Our preamp has a passive volume control, but has active circuitry after it.
    
    So its considered 'active'.
    
    Just because a regular volume control (which in itself is passive) does not mean the circuit is considered passive if active devices are involved! Kal is correct.
Be fussy about words. nt. - Leo loves music 09:37:49 11/08/24 (13)
.
- There is a difference between class AB and class A - Leo loves music 09:52:39 11/08/24 (12)
  BUF03 perhaps is the only opamp in class A mode on this earth.
  - There are other class A opamps- that's not unique nt - Ralph 10:44:12 11/08/24 (11)
    -
    - RE: There are other class A opamps- that's not unique nt - Leo loves music 17:22:26 11/09/24 (8)
      Do you remember the model number of the class A opamps you mentioned? I am very interested. Thanks a lot!
      - NE5534 ... - Ralph 10:53:35 11/11/24 (7)
        
        In Reply to: RE: There are other class A opamps- that's not unique nt posted by Leo loves music on November 09, 2024 at 17:22:26
        
        -just one, common, example.
        
        RE: NE5534 ... - Leo loves music 11:50:54 11/11/24 (5)
        
        In Reply to: RE: NE5534 ... posted by Ralph on November 11, 2024 at 10:53:35
        
        It is good to know that NE5534 is a class A opamp. Wow!!!
        Which planet are you on?
        
        Edits: 11/11/24
        
        Any opamp can be class A - Ralph 12:02:28 11/11/24 (4)
        
        In Reply to: RE: NE5534 ... posted by Leo loves music on November 11, 2024 at 11:50:54
        
        see link.
        https://tangentsoft.com/audio/opamp-bias.html (Open in New Window)
        
        RE: Any opamp can be class A - Leo loves music 12:11:21 11/11/24 (3)
        
        In Reply to: RE: Any opamp can be class A posted by Ralph on November 11, 2024 at 12:02:28
        
        Good point so you can use any cheap opamp in your products.
        
        The class of operation has very little to do with how they sound. - Ralph 12:17:40 11/11/24 (2)
        
        In Reply to: RE: Any opamp can be class A posted by Leo loves music on November 11, 2024 at 12:11:21
        
        Things like gain bandwidth product affect it more. Nice to have low noise too.
        
        RE: The class of operation has very little to do with how they sound. - Leo loves music 12:23:26 11/11/24 (1)
        
        In Reply to: RE: The class of operation has very little to do with how they sound. posted by Ralph on November 11, 2024 at 12:17:40
        
        Very true. When all the people on this planet get used to the sound of class D. They do not miss class A a single bit.
        
        ========================================
        There are two kind of liars. Blink eyes/ do not blink eyes
        
        RE: The class of operation has very little to do with how they sound. - AbeCollins 10:46:12 11/12/24 (0)
        
        In Reply to: RE: The class of operation has very little to do with how they sound. posted by Leo loves music on November 11, 2024 at 12:23:26
        
        I didn't miss Class A way before I started auditioning Class D amps. The Class A amps I had seemed rather smooth, polite, and dynamically challenged. I owned better sounding Class AB amps. To be perfectly honest I don't think it's a "Class" thing. There are good and bad sounding amps in all Classes.
        
        I've had several different Class D amps in and out of my system over the past 25 years. Class D has improved incrementally over time and I find that there are a number of outstanding current generation Class D amps. I've been running a couple with excellent results for the past 5 years.
        
        RE: NE5534 ... - Leo loves music 11:41:23 11/11/24 (0)
        
        In Reply to: RE: NE5534 ... posted by Ralph on November 11, 2024 at 10:53:35
        
        Wow, an old friend.
        
        AI Overview
        Learn more
        ...-
        The NE5534 is a low-noise, single operational amplifier (op amp) that is not specific to a particular class of amplifier. However, class AB amplifiers are a combination of class A and class B amplifiers that can be more efficient than class A while having less distortion than class B.
    - True. But most can't.... - AbeCollins 15:29:13 11/09/24 (1)
      From what I've seen most opamps operating in Class A or one leg of the output biased Class A (single ended), can't dissipate much power. I suppose one can add a transistor buffer at the output - a FET or even an old school bipolar darlington configuration.
      
      Edits: 11/09/24
      - BUF03 can do 1W - Leo loves music 17:12:04 11/09/24 (0)
        
        In Reply to: RE: True. But most can't.... posted by AbeCollins on November 09, 2024 at 15:29:13
        
        and output impedance down to 2ohms. Is that enough?

Post a Followup:

FAQ

Post a Message!

Forgot Password?

Moniker (Username):
Password (Optional):
	Remember my Moniker & Password (What's this?) Eat Me
E-Mail (Optional):
Subject:

Message:	(Posts are subject to Content Rules)

Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:	Automagically notify you when someone responds.

To view your new posting or follow-up, click on the RELOAD or REFRESH button on your browser.

This post is made possible by the generous support of people like you and our sponsors:

VH Audio