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Hoffman Amps Forum image Author Topic: SS_VersionII  (Read 6308 times)

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Offline shooter

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SS_VersionII
« on: July 31, 2018, 12:04:12 pm »
stuff quit breaking for a day so I got a start on this version
I'm putting one of the 10w stereo's in with a 60W mono

version I is getting some attention, but millennial's don't have any more money than starving musicians  :icon_biggrin:

 
Went Class C for efficiency

Offline sluckey

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Re: SS_VersionII
« Reply #1 on: July 31, 2018, 04:22:44 pm »
Is this an electronic project or another art masterpiece? The art kinda reminds me of my first color TV!   :icon_biggrin:
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline shooter

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Re: SS_VersionII
« Reply #2 on: July 31, 2018, 08:26:04 pm »
Yes  :l2:

I hope it will be a poor man's killer front channel.  version 1 is driving a pair of bose 10.2, the fidelity of both the rca amp n speakers gets really close to the best I've heard.
Version II will drive, same bose, and mono will drive either 2 jbls pro series, 15" n horn, or voice of theater 15 n jbl horn.

I do art like most of you do music, so meld the talents, or lack of :laugh:
I am aiming for a hipster, millennial audience, and possibly cash, or not  :laugh:
Went Class C for efficiency

Offline shooter

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Re: SS_VersionII
« Reply #3 on: August 05, 2018, 04:46:09 pm »
doing the gatorclip testing;
the PT I have is shy some volts, but works for now.  My split rail is 56vdc, ideal 80.
.3vacrms puts it a volt low of clipping at the speaker, math there shows 33.6Wrms

I don't have volume controls so driving the mono and stereo amps equally the mono wins!
it'll be awhile to free up parts money to get pieces.

I drove both the Bose and the Altec  a, gotta say the RCA wins for fidelity, the mono wins for lower freqs, gets into full bass while the RCA starts about mid-bass.  which is sorta what I was designing for.
Went Class C for efficiency

Offline shooter

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Re: SS_VersionII
« Reply #4 on: August 24, 2018, 07:41:45 pm »
still experimenting
I've got a meter across the 1 ohm R, measures fine, 'sept idle has about 50mV through the 1ohm, so the meter is at 1/2 scale already.  the winding ohms ~~ 100ohms.  do I put a shunt R, or series R to make 50mV = 0.  It's a really nice meter and I don't wanna crash the needle tooo many times

 
Went Class C for efficiency

Offline PRR

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Re: SS_VersionII
« Reply #5 on: August 24, 2018, 10:59:32 pm »
You can't make 50mV=0 with such a simple circuit.

If you leave the meter in circuit and play audio loud, the meter WILL bang.

What are you trying to meter? Idle current? Why?

Offline shooter

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Re: SS_VersionII
« Reply #6 on: August 25, 2018, 09:57:01 am »
Quote
You can't make 50mV=0
ya, I figured that out later when the fog lifted  :think1:

I'm aiming for "visual" effects, that might actually be useful.

I figured my 2 options, keep it analog, but use  optical coupled, then "re-scale", or digitized 8bit (since the meter dial is 0-250), scale the digital then D/A it back to the meter.  1/2volume range from my fluke is ~ 60 to 90mV, with 50mV idle no signal, hope to have full volume values tonight.
Went Class C for efficiency

Offline PRR

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Re: SS_VersionII
« Reply #7 on: August 25, 2018, 07:03:15 pm »
mA meter, full wave bridge, 5K resistor, directly across the speaker terminals. Will dance to the music, which is probably what you want.

 


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