OK... so now Señor Pass sort of knows my face... so if I grow a beard and show up as a janitor sent by the HOA to clean the stables and the house from all those "cheeps".... "Buenos dias, señor Nelson... ".
Or maybe we rent a Suburban with NV plates in San Rafael... you get something with BIG pockets.. I'll drop you off at the end of the drive way and pick you up two days later? We can do this a couple of times... spend a night in between drinking good IPA in Petaluma.
After a week, we swap cars back to my hidden high performance SUV and high tail it out of NorCal. I'll put you in a plane at LAX, non stop to Milan.
We lit out from Santa Rosa, we was trailed by twenty hounds
Didn't get to sleep that night 'til El Segundo came around
Set out runnin' but we'll take our time
A friend of Tony is a friend of mine
If we get to the airport before daylight
Just might get some SITs tonight
50-50... chance.
Oh wait! shoots... does El Papacito read these forums?
The stereo XA252 SIT has two SITs and two pucks in each chassis and properly ventilated runs reasonably cool... so going mono for the BBB SIT, each unit should still only have two SITs and two pucks.... so unless you've done something truly crazy with the bias... and if only running both channels symmetrically ( balanced )... why would you need the extra cooling of the 500 chassis?
Another thing... will the BBB SIT need to use balanced inputs to get it's full power of will you have some FE circuit that allows the SE input to drive both sides? Will such a set up make the balanced inputs the "purer" path?
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Well it makes music. Iq set at 180mv? Is that right, or 200mv? Sounds amazing, even the wife commented. No idea on temps yet. Running the SET version. Slight hum from toroids, but no noise through the speakers. 30 volt secondaries ended up being 42 volts(damn active bridges) under load at the boards. Played for about 3 hours and nothing popped yet.
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because I was cheapskate in all my past lives, same as in this one, and I did learn something from all that cheapskating - sometimes is cheaper long term if you pony-up in advance
as chaps from origin of your wobblybobbly ttable are used to say - I'm not rich enough to buy cheap
it will, if you leave that small box (preamp?) on top
it's imagined having balanced input, which can be driven in SE fashion, as usually grounding neg input leg (XLR short in 1&3, cable to RCA)
and, as usual, there is slight difference when driving all/any bal input stage in one way vs. another, balanced being better strictly in academic meaning ..... and with proper ones that diff isn't big
just to be shure: BigBadaBoom requires 2 SITs and 2 pucks per channel (f.e. THF51S and the same pucks as in the XA252)? Matched?
yup for 2 SITs + 2 Pucks per channel
nothing needs to be matched
nirvana, eeh?
I really hope that my individual existence doesn't expire yet,
and I wouldn't really like to be freed from reincarnation either
and I wouldn't really like to be freed from reincarnation either
Quick question. I may have missed the answer somewhere in the thread.
I am setting the bias and wondering what the role of JP1 is? Is there an explanation for 'dummies'?
I am setting the bias and wondering what the role of JP1 is? Is there an explanation for 'dummies'?
during setup procedure, having inputs shorted to GND, JP1 open and no load at output, you go first to fiddle with Iq setting
after getting with Iq in ballpark, you need to set output DC Offset
now, with JP1 open, neg leg input isn't firmly grounded in DC domain , so servo function of amp's FE is dominating DC behavior, whatever position of P1 is
put jumper on JP1 (close it) and then neg leg input becomes firmly grounded in DC domain too, so now you have all conditions met to fiddle with P1, set DC Offset at output, that way manually dialing higher level of DC symmetry in input LTP
now - you can leave JP1 open, no pops and no nastiness during power on/off while existence of cap in signal leg can bother your dreams and result in sudden waking in nightmare screams
or you can put JP1 jumper in place, having all DC coupled, still no pops and nastiness
your choice
after getting with Iq in ballpark, you need to set output DC Offset
now, with JP1 open, neg leg input isn't firmly grounded in DC domain , so servo function of amp's FE is dominating DC behavior, whatever position of P1 is
put jumper on JP1 (close it) and then neg leg input becomes firmly grounded in DC domain too, so now you have all conditions met to fiddle with P1, set DC Offset at output, that way manually dialing higher level of DC symmetry in input LTP
now - you can leave JP1 open, no pops and no nastiness during power on/off while existence of cap in signal leg can bother your dreams and result in sudden waking in nightmare screams
or you can put JP1 jumper in place, having all DC coupled, still no pops and nastiness
your choice
Thanks for the swift reply and explanation. That makes good sense, even to me.
I prefer sweet dreams and no nightmares, but will of course be fiddling with the jumper.
At the moment, the amp is making music on some small speakers. So far so good!
I prefer sweet dreams and no nightmares, but will of course be fiddling with the jumper.
At the moment, the amp is making music on some small speakers. So far so good!
my amps are not choosy regarding speakers....... so small ones are as good as big ones, as long you have wide green
Cheers. These speakers would literally fit inside the amp/chassis...and won't do justice to anything but a 90s mini-stereo-system.
Anyway, I should soon have the courage to hook up the amp to 'larger' speakers.
Anyway, I should soon have the courage to hook up the amp to 'larger' speakers.
Here it is. Still planning to add speaker protection. It warms up the chassis quite nicely 🙂
