[RE-wrenches] Sound Equipment Inverter

[Ray]

Hi Jay;

Another great question, that I can't answer.  The continuous watts would 
probably meter at 100 watts or so, but the transient peaks can be quite 
a bit more. How much more, depends on how fast your meter capture is, 
but the ear can hear up to 20 kHz, and my meter can't catch transients 
anywhere close to that.

Having a power supply that can handle those musical transients is 
important, even if I can't measure it.  The power supply can cause some 
compression of the sound.  I've already run into that, with transformers 
on the tube amps, inverter sizing, battery sizing, and Vac.

As Dave mentioned, the AC voltage can really matter to these amps, and 
to bring EVH (rip) again into a seemingly unrelated industry, Eddie used 
a Variac to feed his Marshall amps lower voltages, to operate at lower 
volume to get his "Brown sound".

All that aside, I'm thinking an Exeltech XP1100 might be plenty, and is 
a known, high quality waveform.  But then I'd have to add a separate DC 
charger with its own possible noise issues.   I've used Samlex very 
little, but seen their inverters survive serious abuse in others' 
installs, so I look forward to hearing more about Bryan's studio build, 
too.


Ray Walters
Remote Solar
303 505-8760

On 10/22/20 5:29 PM, Jay wrote:
> Hi Ray
>
> How many watt do you need?
>
> Jay
>
>> On Oct 22, 2020, at 4:42 PM, Ray <ray at solarray.com> wrote:
>>
>> Hi All;
>>
>> I've just had an inquiry on building a portable sound stage and recording setup.  Traditionally we've always used Exeltech, as they've had the cleanest output, with background buzz on tube amps being lower than grid power.  Modsine were horrible, Old Trace SWs were pretty intolerable, Magnum's were usable, but still noticeably more buzz than grid.  I think THD is roughly associated with the background buzz, but there might be certain harmonics that are particularly problematic.  I haven't gotten into looking at the separate harmonics relative to what induces the most noise in these old vacuum tube circuits.
>>
>> This is a 48 v application that also needs a built in charger with transfer switching.  Exeltech does not appear to have anything in that department.  Any other choices?  How are Samlex?
>>
>> As always, thanks in advance for your time and expertise,
>>
>> -- 
>> Ray Walters
>> Remote Solar
>> 303 505-8760
>>
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