Mods? How crazy do you want to get? Add caps to the power supply? Swap transistors in the front end? Rebuild it as an X? (Don't take me up on that last one. I've got too many projects on my plate already.)
The amp can be bridged by inverting the input to one channel and using the positive outputs <i>only</i>. Leave the negative outputs alone. The power will be x4 until you exceed the available current; it's a good idea to stick with 8 ohm loads so that this dosn't happen too quickly.
I've got two of the original S-500s. They make good low frequency amps. The mids and highs are a little cloudy, but still match or exceed a number of the units on the market today. Ditto for imaging and detail retrieval.
Grey
The amp can be bridged by inverting the input to one channel and using the positive outputs <i>only</i>. Leave the negative outputs alone. The power will be x4 until you exceed the available current; it's a good idea to stick with 8 ohm loads so that this dosn't happen too quickly.
I've got two of the original S-500s. They make good low frequency amps. The mids and highs are a little cloudy, but still match or exceed a number of the units on the market today. Ditto for imaging and detail retrieval.
Grey
I have a nice fix for that: new front end and higher bias.
I believe I've already posted the last (never to be produced)
front end for the Stasis series, delivered as I walked out
the door.
If you can't find the reference, let me know and I'll repost it.
It was remarkable for being totally DC coupled with almost no
drift at all and was improved in every respect over its
predecessors.
I believe I've already posted the last (never to be produced)
front end for the Stasis series, delivered as I walked out
the door.
If you can't find the reference, let me know and I'll repost it.
It was remarkable for being totally DC coupled with almost no
drift at all and was improved in every respect over its
predecessors.
Nelson Pass said:
I cannot open that file can anyone help!
mike m said:I cannot open that file can anyone help!
Attachments
Yep, I was walking out the door about then, and this would
be the last piece of schematic I left, along with my white
paper "IGBT's: Threat or Menace"
Yeah, I know, I really amuse myself with that kind of humor.
I believe this schematic made it into some updates, but not
production. Its primary virtue was that there was almost
no thermal drift, as all the temperature coefficients of each
component were carefully measured and calculated and the
circuit was designed to null the PN junction drift throughout.
be the last piece of schematic I left, along with my white
paper "IGBT's: Threat or Menace"
Yeah, I know, I really amuse myself with that kind of humor.
I believe this schematic made it into some updates, but not
production. Its primary virtue was that there was almost
no thermal drift, as all the temperature coefficients of each
component were carefully measured and calculated and the
circuit was designed to null the PN junction drift throughout.
The paper discussed the difficulties of matching the
devices due to their dual device nature and the
inability to bias the mosfet part of the part at a
greater current than the Base current of the Bipolar
part. In an ordinary circuit, the driver is biased at
higher than the draw of the following part, which
improves the linearity and speed.
devices due to their dual device nature and the
inability to bias the mosfet part of the part at a
greater current than the Base current of the Bipolar
part. In an ordinary circuit, the driver is biased at
higher than the draw of the following part, which
improves the linearity and speed.
Has anybody actually done this modification or who would I dont think hans willplanet10 said:
How would I do it. Reverse the inut of channel 2 and add to channel 1? Illenema@yahoo.comGRollins said:Mods? How crazy do you want to get? Add caps to the power supply? Swap transistors in the front end? Rebuild it as an X? (Don't take me up on that last one. I've got too many projects on my plate already.)
The amp can be bridged by inverting the input to one channel and using the positive outputs <i>only</i>. Leave the negative outputs alone. The power will be x4 until you exceed the available current; it's a good idea to stick with 8 ohm loads so that this dosn't happen too quickly.
I've got two of the original S-500s. They make good low frequency amps. The mids and highs are a little cloudy, but still match or exceed a number of the units on the market today. Ditto for imaging and detail retrieval.
Grey
Nelson Pass said:
Nelson,
This all looks very interesting, however do you have a schematic
that you can provide that covers the circurity on both headers.
I have an S300 I would like to try this out on.
Regards
Jim Wilson
You are assuming I have a schematic of this amp, as if
Nakamichi sent me one. Keep in mind that this was
primarily a licensing deal, and Nak was/is free to do what
they like, particularly as Threshold doesn't appear to
exist any longer and the patent is expired.
pass/ - he's listening to Rasa Exotica, which Jam would
probably like.
Nakamichi sent me one. Keep in mind that this was
primarily a licensing deal, and Nak was/is free to do what
they like, particularly as Threshold doesn't appear to
exist any longer and the patent is expired.
pass/ - he's listening to Rasa Exotica, which Jam would
probably like.
Re: You are feeling sleepy!
Not a bad thing IMHO... and now that he is enlightened his content has risen dramatically...
dave
jam said:Halo is having far too much influence on members of this fourm......
Not a bad thing IMHO... and now that he is enlightened his content has risen dramatically...
dave
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