Re: Early solid state power amps


"Mr.T" <MrT@home> wrote in message
news:43debf80$0$26973$afc38c87@xxxxxxxxxxxxxxxxxxxxxxx
>
> "Trevor Wilson" <trevor@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
> news:43deb218$1@xxxxxxxxxxxxxxxxxxxxxxxx
>> >> The title of the thread is VERY clearly: early solid state power
>> >> amps."
>> >> Can you state that the IC you SEEM to remember was relevant to
>> >> the power amp function? Which other POWER AMPS used "audio amp
>> >> IC's" in the 1960's as you claim?
> <snip>
>> * The DC300A used OP amps in the pre-driver stages. The DC300 did not.
>
> OK, I only owned a DC300A so wasn't sure, hence the question mark.
>
>> * The discussion is about POWER amps, not driver stages.
>
> I'm sorry, I can't see where is says *POWER AMP IC's*, only "audio amp
> IC's"
> used in Power amps.

**Here is the original post:

---
When did decent solid state power amps become available? Were they direct,
capacitor or transformer coupled to the load. Back in the 60's when the
first audio amp ICs became available for battery powered radios and such,
the engineers coupled the output through a transformer! It seemed hard to
wean them off the transformer. Finally in the 70s...
---

Note the reference to a transformer.

> The difference may be too subtle for you?

**Nope. No one denies the existence of ICs used as Voltage amplifiers in the
1960s.

> An op-amp *IS* an "audio amp IC". The driver stage *IS* part of the power
> amp.

**Part of, but not the entire power stage.

>
>> > Both the DC-150 amplifier and IC-150 pre-amplifier did in 1970, for
> sure.
>> **And again.
>
> Ditto.

**Ditto again.


--
Trevor Wilson
www.rageaudio.com.au


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