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Old 21st October 2009, 01:23 AM   #631
dr_vega is offline dr_vega  United States
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An advantage of the nice small Tripath amps that has not been discussed is mounting them very close to the speakers thereby reducing the speaker cables to almost nothing.

I have mounted a Sure amp directly on the back of each of my Open Baffle speakers. Each Sure amp drives a 2-way speaker (I have active crossovers). My speaker cables are about 4 inches long. I'm using Cat-5 for them.

This configuration gets rid of the long speaker cables and replaces them with long interconnects between the preamp/crossover and the amps. But interconnects, carrying tiny amounts of current, do far less damage to the sound than speaker cables carrying large currents.

Even using mid-fi interconnects (since my crossover has XLR outputs, I'm using professional, rather than audiophile, cables), the improvement was dramatic. I had been using 6' long, 10 AWG OFC speaker cables. Getting rid of them made the sound much clearer and sweeter. I had been happy with the 10 gauge cables, but I'm much happier now that they are gone.

You can spend a ton of money improving your speaker cables, but a better, and cheaper, solution is to just get rid of them. Buying a second Sure amp is far cheaper than buying premium cables, and the result is much better.

It's worth considering, even if you have speakers with internal crossovers and you only use one side of each amp.

-dr_vega
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Old 21st October 2009, 09:43 AM   #632
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Originally Posted by wushuliu View Post
On the T-forum people are removing the gain switches, it seems, because there is an improvement in sound. Is this better than just leaving the gain switches on OFF? Google translate is helpful, but I am a little confused on this issue.
we don't need google transalte, but we also are a little confused on this issue

Theoretically this tweak would be insignificant (according to observation wrote here before) Author fo this tweak gave some explainations about false contacts, or very near open contacts, which would not be ok..

Both here and there, it's quite a common and never-contrasted idea that this board suonds better with low-gain settings, so, if you don't need the other gain settings, you don't need these switches, so you can remove them.. less is better! just joking..

i don't need other gain settings, but i left switches in place, i don't care for them..

i also left the protection diodes, although it seems (both here and there) that board is better performing without them.. any comment on this tweak?
i'm not sure if i'll remove them, especially the one before the 5V regulator, 0.6v more dropout voltage on it, so a little more heating, but the goods?

Last edited by madqwerty; 21st October 2009 at 09:53 AM.
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Old 21st October 2009, 04:32 PM   #633
ElFishi is offline ElFishi  Europe
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Originally Posted by madqwerty View Post
i also left the protection diodes, although it seems (both here and there) that board is better performing without them.. any comment on this tweak?
i'm not sure if i'll remove them, especially the one before the 5V regulator, 0.6v more dropout voltage on it, so a little more heating, but the goods?
I just found the amp goes better with more voltage so I guessed I have the voltage over the diodes, too.
If you are worried about the regulator you might want to feed it separately anyway. Audio1st showed how to cut the traces. Im planning to add a floating preregulator, I'll report how that looks once I'm done testing.
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Old 21st October 2009, 05:32 PM   #634
sendler is offline sendler  United States
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Default Short wires and dual mono

Quote:
Originally Posted by dr_vega View Post
An advantage of the nice small Tripath amps that has not been discussed is mounting them very close to the speakers thereby reducing the speaker cables to almost nothing.

I have mounted a Sure amp directly on the back of each of my Open Baffle speakers. Each Sure amp drives a 2-way speaker (I have active crossovers). My speaker cables are about 4 inches long. I'm using Cat-5 for them.

This configuration gets rid of the long speaker cables and replaces them with long interconnects between the preamp/crossover and the amps. But interconnects, carrying tiny amounts of current, do far less damage to the sound than speaker cables carrying large currents.

Even using mid-fi interconnects (since my crossover has XLR outputs, I'm using professional, rather than audiophile, cables), the improvement was dramatic. I had been using 6' long, 10 AWG OFC speaker cables. Getting rid of them made the sound much clearer and sweeter. I had been happy with the 10 gauge cables, but I'm much happier now that they are gone.

You can spend a ton of money improving your speaker cables, but a better, and cheaper, solution is to just get rid of them. Buying a second Sure amp is far cheaper than buying premium cables, and the result is much better.

It's worth considering, even if you have speakers with internal crossovers and you only use one side of each amp.

-dr_vega
Great post. That's one of those ideas that seems so obvious as to forget to mention. I normally have dual mono amp chassis with 18 inch speaker cables. The smaller, $17.00 150watt power supply might work well for dual mono with one channel driven.
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Old 21st October 2009, 06:37 PM   #635
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Originally Posted by sendler View Post
Great post. That's one of those ideas that seems so obvious as to forget to mention. I normally have dual mono amp chassis with 18 inch speaker cables. The smaller, $17.00 150watt power supply might work well for dual mono with one channel driven.
Interesting. So it's preferable to have long interconnects (from say, a preamp) to the amps/speakers than speaker cables covering the same distance?
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Old 21st October 2009, 08:35 PM   #636
dr_vega is offline dr_vega  United States
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Originally Posted by wushuliu View Post
Interesting. So it's preferable to have long interconnects (from say, a preamp) to the amps/speakers than speaker cables covering the same distance?
That's been my experience and I think there is pretty general agreement on that. Because speaker cables carry higher voltages and currents, all of the bad things are magnified, except outside noise that filters in. If the interconnects pickup noise, the noise is amplified when it goes through the amp. Noise the speaker cables pick up doesn't get amplified. That's why speaker cables are seldom shielded.

The next big step is to get rid of the interconnects, too. I'm using a modded Behringer DCX2496 digital crossover. I have a second one that I have not yet modded. I will put one crossover next to each speaker and run 1 foot interconnects to the amps. Interconnects from the source (CD player, etc) to the crossovers are digital and aren't supposed to degrade the sound (let's save that discussion for another thread).

BTW, Scott (sendler) has a great website with good info on modding the Behringer digital gear. He also does the mods for those who don't want to diy.

-dr_vega
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Old 21st October 2009, 08:47 PM   #637
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Originally Posted by dr_vega View Post
That's been my experience and I think there is pretty general agreement on that. Because speaker cables carry higher voltages and currents, all of the bad things are magnified, except outside noise that filters in. If the interconnects pickup noise, the noise is amplified when it goes through the amp. Noise the speaker cables pick up doesn't get amplified. That's why speaker cables are seldom shielded.

The next big step is to get rid of the interconnects, too. I'm using a modded Behringer DCX2496 digital crossover. I have a second one that I have not yet modded. I will put one crossover next to each speaker and run 1 foot interconnects to the amps. Interconnects from the source (CD player, etc) to the crossovers are digital and aren't supposed to degrade the sound (let's save that discussion for another thread).

BTW, Scott (sendler) has a great website with good info on modding the Behringer digital gear. He also does the mods for those who don't want to diy.

-dr_vega
Ah. Thanks doc. Looks like I'll be getting another amp The Behringer I'll be saving for down the road, when I get a better handle on the speaker design side of things. Baby steps!
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Old 21st October 2009, 09:13 PM   #638
Theo404 is offline Theo404  United Kingdom
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Originally Posted by dr_vega View Post
Because speaker cables carry higher voltages and currents, all of the bad things are magnified, except outside noise that filters in. If the interconnects pickup noise, the noise is amplified when it goes through the amp.
Care to elaborate on what 'bad things' speaker cables do that interconnects are free from?
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Old 21st October 2009, 11:10 PM   #639
dr_vega is offline dr_vega  United States
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Care to elaborate on what 'bad things' speaker cables do that interconnects are free from?
We're getting way off topic for this thread. You can find lots info about wiring in many forums. It remains a science and an art and a mystery. There's lots we know and lots we suspect, and lots we don't know.

The core issue is that current passing through a wire creates an electromagnetic field. This field affects how the current flows. The more current is flowing, the stronger the electromagnetic field created and the more it affects the flow of current. Therefore it's better to run the current through the wire while the current is still small.

In concert stage setups, the amp racks are placed right behind the speaker stacks. The snake cables run the mic level signals out to the mixer (often more than 100 ft), the mixer preamps the signal to line level and returns it down the 100 ft snake to the amp racks where it is amplified to speaker and runs to the speakers on 10 ft speaker cables. This is done primarily for sound quality reasons, although cost is sometimes a consideration, too.

It would be a lot more convenient for the sound engineer to have the amps up there with the mixer, but sound quality dictates that the amps be next to the speakers.

-dr_vega
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Old 21st October 2009, 11:31 PM   #640
Theo404 is offline Theo404  United Kingdom
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Sorry for OT, thanks for the response.... I need a think! I jumped to the obvious conclusion that having long low level cables would just result in worse SNR.... hmmm.
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