| Will |
I know this pre-amp is kinda dated, but yes, I finally found the time to populate the PCB and get it up and running.
What do I think of it ? Like Nelson mentioned in the literature, it's dry... Details are good, just that the tonality is not moist enough... Moisture that you get from a good tube gear..
Of course it's not a tube pre-amp ? But can it be made to sound like one ?
Any takers on how do I improve this portion of the audio spectrum ? Of course building another pre-amp is out of the question. The quest is really to optimise whatever you've got.
BTW I'm biasing it to only 7volts as any higher will bring out the hardness quality.
regards,
Will. |
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| ingvar ahlberg |
Hi Will
Beeing a true fan of NP itīs a bit sad to say that i donīt think this is a very good preamp, actually its more of a low power output amp used as a buffer for line sources and the irf transistor used is a standard switching device designed for power supplies and such, this goes for the devices used for output in Zen and Aleph amps too but that job seems a lot more suitable.
One way to change (improve?) the character of this line stage could be to replace the irf 610 with paralleled small signal fets (2SJ74 for instance) also introducing one drain resistor each, same as in an output stage. Another good way to add moisture is to put a record on and indulge in a small glass of Caol Ila (or i nice large glass of Amarone if a thirsty friend rang on the doorbell) |
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| GRollins |
People have been trying to make solid state sound "like tubes" for years. Unfortunately, if you want the sound of tubes, you'll have to use tubes to get it.
The funny thing is that--with the arguable exception of bass--no one ever wants to make tubes sound like solid state...
Grey
EDIT: When you say you're biasing the MOSFETs to 7V, do you mean that you're running 7V rails? |
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| Will |
| quote: | Originally posted by GRollins
EDIT: When you say you're biasing the MOSFETs to 7V, do you mean that you're running 7V rails? |
Grey,
That 7v would be the voltage after the trimpot WRT ground. Seriously, you'd also think there's no hope to it ?
ingvar,
Thanks for the sugestion. That's sad to hear from another person that agrees with the poor performance of BOZ.
Sigh... |
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| GRollins |
No hope.
If it were easy to make solid state sound like tubes, it would have been done long ago. If you want tube sound, you use tubes. If you want solid state sound, you use transistors. The closest you can get with solid state is to run the bias current way, way up. Watch the heat dissipation. If it's tube sound you're seeking, it still won't sound right to you, but it's the best you're going to get.
Grey |
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