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Minimum gain for 2020?
Minimum gain for 2020?
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Old 15th November 2005, 03:13 PM   #1
Nuuk is offline Nuuk  United Kingdom
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Default Minimum gain for 2020?

I've just looked through the datasheet for the Tripath 2020 chip but can't see any reference to what is the lowest possible gain setting.

Can anybody please tell me how low I can go as I would like to set up one of the 2020 amps to run with a valve pre-amp that has quite high gain. I am currently using that valve pre-amp with an OPA541 chip amp with a gain of 9, and that works well!
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Old 15th November 2005, 04:18 PM   #2
dillo is offline dillo  Italy
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Hello Nuuk,
I'm building an Autocostruire, and I have the same problem: finding the correct gain.
I think you can go down as you like; on the instructions of the kit they give values also for unity gain, so I think it works well.
I'm going to test a gain of 2.5.
What is the gain, or sensitivity, of your pre?

Goodbye,
Angelo
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Old 15th November 2005, 04:25 PM   #3
Nuuk is offline Nuuk  United Kingdom
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Thanks for that Angelo - I didn't think to check the excellent instructions that go with the Autocostruire amp!

I haven't measured the gain of the pre-amp. I previously tried it with the power section of an Arcam A60 amp and couldn't get the volume control off position 1!

This is the circuit of the pre-amp.
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Old 16th November 2005, 10:31 AM   #4
Nuuk is offline Nuuk  United Kingdom
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I have altered the gain of the Autocostruire 2020 to around 8 and hooked it up to the valve pre.

It is noticeably more 'precise' than the OPA541 chip amps that I used yesterday but in some ways, I prefer the chip amp!

I'm a little troubled as to why I don't like the class-T amps as much as some people do and have given the matter a lot of thought.

For me, the class-T's are a little too precise, too analytical! I hear (very clearly) the elements of what ever I am listening to. But in some ways, that distracts from the overall presentation.

When I go to a live performance, I listen to the performance and am not really aware of individual voices or intruments (unless it is a solo of course). Similarly, when I eat a meal, I like the taste of the dish that I am eating and don't really want to taste all the individual ingredients on their own.

Remember how the music on the CD, LP etc gets to us. It is recorded through microphones. The microphone is (accurately we have always hoped) picking up the sound at that location. With just a pair of ears, and sitting further away than the microphones are placed, we hear something different, in fact we hear the sound from not just one microphone but as many that are used .

All this has not mattered too much in the past. The individual elements of a recording have been somewhat 'mixed up' again by the electronics that produce the CD or LP and those that play it. Now it would appear that our hi-fi's are capable of playing everything exactly as it was picked up by the microphones and mixed.

Perhaps recording engineers need to look again at how they record music now that the resolving power of home hi-fi has reached the level that it has with the class-T amplifiers.

Just my two penneth (ten cents) worth but food for thought I hope!

As regards the pre-amp - I'm converted, it's the best pre that I have tried to date!
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Old 16th November 2005, 10:51 AM   #5
dnsey is offline dnsey  United Kingdom
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I have always understood (and found) that the ability to hear individual threads in a piece of music was to be encouraged and cultured.
Most classical and much popular music (especially jazz) is written to be heard that way - the interaction of the various parts is a positive aspect of the art and its appreciation. That's not to say, of course, that the resulting symphony doesn't have value, but it's another element of enjoyment.
What do others think?
(Sorry for hijacking - if there are many replies this might warrant another thread)!
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Old 16th November 2005, 11:36 AM   #6
Nuuk is offline Nuuk  United Kingdom
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Quote:
(Sorry for hijacking - if there are many replies this might warrant another thread)!
No don't worry, it's worth debating!


Quote:
I have always understood (and found) that the ability to hear individual threads in a piece of music was to be encouraged and cultured.
I know what you are saying about jazz etc and that's not quite what I meant about hearing things coherently as opposed to individually. It's hard to put into words but this is more of a hi-fi issue than a musical one.
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Old 16th November 2005, 03:14 PM   #7
tianguis is offline tianguis  United States
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Default Round earth/ flat earth

Nuuk:
Your post about preferring the chip amp to the tripath jives with what I've seen. I recently demo-ed an ICEpower amp I built to a group of about twenty audio heads here in New York.
The ICE is even more precise and revealing than any of the Tripath amps I've built or heard, relentless in digging out all the detail. I prefer it for that reason, as it tells me lots more about other components, not to mention the recording. However, the three folks there who use Naim equipment in their systems preferred the (to my ears) less-revealing, slightly colored sound of a pair of Stello monoblocs.
I guess it really does boil down to personal preferences rather than "better" or "worse".

Regards,
Larry Welsh
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Old 16th November 2005, 03:24 PM   #8
Nuuk is offline Nuuk  United Kingdom
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Quote:
I guess it really does boil down to personal preferences rather than "better" or "worse".
That's very true Larry and why not. I'm a vegetarian but many people prefer a steak. So why shouldn't it be the same with music too?

And of course the other components in our systems, and the listening room, make a difference too. But I still stand by what I said about recording quality because obviously, the more revealing a system, the more pronounced the faults in the recording!
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