Illusus: Actually can you e-mail me at plusmoi@gmail.com with the info (specs, price, shipping info, etc).
Capacitors do part of the trick
Hi Guys, I bought 2 T-amps a while ago and started playing with one of them. I keep a vanilla version for comparison base. I must say, only connecting some capacitors at the 12V input helped it survive more bass.
I must say I was amazed of the precision and quality of those little amps. The tone was very different than my dads high end transistor amps. He told it really got close to lamps.
Next we changed all the connectors to reduce impedance but primarily for easier plug and unplug. The funny thing is that those tiffany connectors costs more than double the price of the amp each.
I have attached a picture of the amp. It is photographed a my home and not at my dads so don't critique the environment or cables please...
I plan on buying 2 more and use a digital cross over to really split in 4 distinct channels (sub, mid, tweeter and kelly horns) while respecting the phase...
Im gonna use this system on my home entertainment station using that audio card:
http://techgage.com/article/asus_xonar_d2_sound_card/
I use a very good recording of Janis joplin for voice tests and I use Jazz at the pawn shop for staging tests.
Allright ill give you some results when I get it all.
Thanks
Hi Guys, I bought 2 T-amps a while ago and started playing with one of them. I keep a vanilla version for comparison base. I must say, only connecting some capacitors at the 12V input helped it survive more bass.
I must say I was amazed of the precision and quality of those little amps. The tone was very different than my dads high end transistor amps. He told it really got close to lamps.
Next we changed all the connectors to reduce impedance but primarily for easier plug and unplug. The funny thing is that those tiffany connectors costs more than double the price of the amp each.
I have attached a picture of the amp. It is photographed a my home and not at my dads so don't critique the environment or cables please...
I plan on buying 2 more and use a digital cross over to really split in 4 distinct channels (sub, mid, tweeter and kelly horns) while respecting the phase...
Im gonna use this system on my home entertainment station using that audio card:
http://techgage.com/article/asus_xonar_d2_sound_card/
I use a very good recording of Janis joplin for voice tests and I use Jazz at the pawn shop for staging tests.
Allright ill give you some results when I get it all.
Thanks
You are right. But since I live in a condo, I really try to avoid blasting too much bass. At my dads place we drive the subs with his LIBERTE transistor amp and mids and tweeters with the Tamp. We get really good results.
Nevertheless, with the capacitors, the amp survives more bass. Once I am set-up with a good cross over, I could just substitute the bass amp for somthing more powerful.
Originally I attached a picture but it doesnt seem to work.
Nevertheless, with the capacitors, the amp survives more bass. Once I am set-up with a good cross over, I could just substitute the bass amp for somthing more powerful.
Originally I attached a picture but it doesnt seem to work.
You will also find the T-amp capable of more bass if you up the input voltage to the limit (typical max per datasheet is 13.2V, but others have used SLA battery or a linear supply at up to 14V ok so long as you have two things:
1) The chip heatsink is thermally bonded to the PCB. Earlier revisions of T-amp had a massive solder slug 'sinking the chip by large thermal vias on the PCB, but latter PCBs need either that solder added (carefully, since you don't want to heat the whole thing up enough to fry the chip) or a thermally conductive epoxy injected into the junction area. Since I am not aware of any "epoxy" that can be injected as-is, rather than being mixed first then no longer being in a higher pressure syringe, it seems the solder is the easier although more dangerous method.
2) You're right, added capacitance helps a lot to reduce power rail droop. What helps even more is a linear regulation stage or at least a basic shunt regulator stage and/or similar capacitance multiplier stage. The idea being, if all you have is about 13.2V to work with, make sure it always stays that high.
Even so, driving a sub is a poor use of a T-amp. There are other Class-D/T chips that are suited for it, and the T-amp's virtue is it's transparency and detail which is mostly lost in the lower frequencies. IMO, you would be as well off picking some random gainclone-like chipamp for sub configuration even if it's not playing very loud, it would be best not to push a T-amp this hard as it isn't designed for continual high current output even when left within it's limits at 13.2V. I even epoxied a heatsink to the top epoxy-casing area on my T-amp chip and still I find it is best left to full range or mid and upper amplification, not a sub.
1) The chip heatsink is thermally bonded to the PCB. Earlier revisions of T-amp had a massive solder slug 'sinking the chip by large thermal vias on the PCB, but latter PCBs need either that solder added (carefully, since you don't want to heat the whole thing up enough to fry the chip) or a thermally conductive epoxy injected into the junction area. Since I am not aware of any "epoxy" that can be injected as-is, rather than being mixed first then no longer being in a higher pressure syringe, it seems the solder is the easier although more dangerous method.
2) You're right, added capacitance helps a lot to reduce power rail droop. What helps even more is a linear regulation stage or at least a basic shunt regulator stage and/or similar capacitance multiplier stage. The idea being, if all you have is about 13.2V to work with, make sure it always stays that high.
Even so, driving a sub is a poor use of a T-amp. There are other Class-D/T chips that are suited for it, and the T-amp's virtue is it's transparency and detail which is mostly lost in the lower frequencies. IMO, you would be as well off picking some random gainclone-like chipamp for sub configuration even if it's not playing very loud, it would be best not to push a T-amp this hard as it isn't designed for continual high current output even when left within it's limits at 13.2V. I even epoxied a heatsink to the top epoxy-casing area on my T-amp chip and still I find it is best left to full range or mid and upper amplification, not a sub.
!: I got a picture attached on the D-amp gallery.
I modified 2 T-amp so far. I kept the original casing but took out the huge battery compartment. I changed all connectors and added 50000 uF on a switching power supply. And I have a second cleaner version with 8000uF inside the amp (very crowded) that I power with a regulated 13.5V. Both deliver good bass but since I finished that this weekend, I didnt test them much yet.
And I checked for my heat sink and I do have this soldering slug connected to a 1 inch square surface on the PCB.
I have more pictures that I will post shortly.
I modified 2 T-amp so far. I kept the original casing but took out the huge battery compartment. I changed all connectors and added 50000 uF on a switching power supply. And I have a second cleaner version with 8000uF inside the amp (very crowded) that I power with a regulated 13.5V. Both deliver good bass but since I finished that this weekend, I didnt test them much yet.
And I checked for my heat sink and I do have this soldering slug connected to a 1 inch square surface on the PCB.
I have more pictures that I will post shortly.
Does someone have 2 power supplies for sale? I'll be using one for my T-amp and the other one for my "T-preamp" (http://www.tnt-audio.com/ampli/t-preamp_e.html).
thanks
thanks
linear or switching?
seems like many recommend 12 or slightly hight V, and about 2amp, which is ideal?
linear or switching?
does this seem ideal?
http://www.mcminone.com/product.asp?catalog_name=MCMProducts&product_id=28-2200
gychang
seems like many recommend 12 or slightly hight V, and about 2amp, which is ideal?
linear or switching?
does this seem ideal?
http://www.mcminone.com/product.asp?catalog_name=MCMProducts&product_id=28-2200
gychang
Attachments
Re: linear or switching?
A bit OTT price and feature-wise (a 36' mains cord?), though the output voltage options may come in for other applications. For a dedicated supply, mine's similar to this SMPS one - cheaper and a bit more in reserve.
gychang said:
A bit OTT price and feature-wise (a 36' mains cord?), though the output voltage options may come in for other applications. For a dedicated supply, mine's similar to this SMPS one - cheaper and a bit more in reserve.
I've also been using something similar with good results. I sold a boatload to other members, none have complained. I use them for everything. If you take them apart and isolate the grounds you can wire them in series for a +/- 13.8V supply. Ive parallel/series-ed them to get many other VA combinations (PSU for gainclones, op-amp projects...etc). They are quiet, cool, stable and cheap.
Re: Re: Re: linear or switching?
I got mine from Rapid, (12V 3.8A, needs a power lead)
thedman said:
I got mine from Rapid, (12V 3.8A, needs a power lead)
Fortron Source
A tip from the computer repairman on power, and a few other power goodies that I found out by experimentation. Want bigger watts from your T-amp?
There are some nice computer power supplies out there, around $35 or so. Fortron Source, Sparkle (used in commerce servers) all have an orange screw to regulate the voltage. Be sure to regulate the voltage under load. Um, that's a potentiometer, and sometimes its white.
A 1/2" power staple can be inserted into the ATX plug at the clip area to make it stay on for testing, however this is the exact location that your power switch should be.
The Fortron Source have delayed start built in, which could be good for amplifiers, and they max specs at 13.6v, although it could do more if you want. Factory standard, they do 11.9v, rock steady, bulletproof, and clean.
"Big Fan" Switching models are the quietest, and, of course that fan can run off the 5v rail or you can just put an LED on the 5v rail. Without eating the hot air from a computer, the fan is potentially unnecessary, although the PSU enclosure isn't designed for convection (passive draft) cooling. So, without a fan, it would need a bottom intake and a top output for air.
The "Single Rails" supply is easier to manage than a "dual rails" supply, since all PC power supplies must have a load on all the rails. Fortunately, the Single Rail models (for office PC) are less expensive.
Other tips:
If there's several potentiometers (the aforementioned orange screw), then voltage is probably the one stuck out on a daughter card at a very weird angle (FC400 and larger).
A caution: The cause of death for a computer is usually the PSU sending out a dirty signal, so recycling from an expired computer isn't usually advisable.
Anywhere a hot wire goes, wrap a ground wire right along with it, even if it doesn't connect on the other end. Otherwise magnet chokes are good instead.
The extra price "decorative" and hippie (APFC) power supplies, both, usually make more noise, not less. At the extra price category, the Blue colored Fortron Source product is inferior to the plain unpainted version, so don't pay too much for any brand of "decorative" PSU because decorations subtract cost margin for what's inside.
A nice big capacitor, like 2200uf (right across the 12v line, neg to neg, pos to pos, just like a battery in paralell) can smooth the little voltage drops. That, I believe, is called a "smoothing" cap, and the benefit comes at a cost of creating a bit more "pop" when the amp is turned on.
A smoothing cap (as described above) even works on a wall-wart to keep the vocals from clipping when the bass hits hard; although, a wall-wart isn't going to keep up with classical or complex music that doesn't give it a "nap" so it can charge up that cap.
Maximum specs for the T-amp:
*maximum specs require heat sink and ventilation.
13.5 volts actual (13.2 on paper), conforming to automotive specs. At that rate, there needs to be additional load on the PSU in addition to the amplifier so that the voltage never peaks higher.
Reference load of 2 ohms this way*:
NOT two 4 ohm speakers per channel (reference load 1.5 ohms)
Three 8 ohm speakers per channel is fine (reference 2 ohms)
One 8 ohm and one 4 ohm per channel is fine (reference 2 ohms)
One DVC and one 8 ohm per channel is fine (reference 2 ohms)
Two 8 ohm speakers per channel is fine (reference 3 ohms)
One 4 ohm speaker per channel is fine (reference 3 ohms)
Crossovers:
Crossovers may purposefully contain shorting components, such as the textbook 2nd order crossover, and L-pads. These typical components sacrafice power to make nicer response curves of speaker drivers--they do increase load while decreasing dynamics.
A more ideal example for a small amplifier is a 1st order plus zobel and BSC, teamed up with a paper cone piezo that has a 50 ohm (reduces capacitive load) and 0.063uf cap (adjusts volume output) in series with it. Now, that is a light load indeed, although possibily needing heavy gauge inductors and/or an array / pipe enclosure.
Caps and listening fatigue:
Electrolytic input filter caps really do make more bass power. For sure 4.7uf electrolytic is more accurate on popular music, and a big effect for classical--more of a front row seat.
Believe it or not, a Nichion 4.7uf ($1) is a "can do" for big dynamics.
For those who don't want their house shaking, then 3.3uf electrolytic or 2.2uf poly can make less bass, with more power left over towards clean vocals.
Hey guys!
That's all I've found out so far.
My Sonic "T" is happily outputting about 20 watts per channel.
Unfortunately, my particular amp is unhappy with its volume control, so that it insists on either very loud playback or almost none.
Of course its the same amp with the big electrolytics, big PSU, tank cap, smoothing cap, and the reference load at max.
Its like Tim Allen on Home Improvement--Too Much Power. At least then you know when you have enough.
A tip from the computer repairman on power, and a few other power goodies that I found out by experimentation. Want bigger watts from your T-amp?
There are some nice computer power supplies out there, around $35 or so. Fortron Source, Sparkle (used in commerce servers) all have an orange screw to regulate the voltage. Be sure to regulate the voltage under load. Um, that's a potentiometer, and sometimes its white.
A 1/2" power staple can be inserted into the ATX plug at the clip area to make it stay on for testing, however this is the exact location that your power switch should be.
The Fortron Source have delayed start built in, which could be good for amplifiers, and they max specs at 13.6v, although it could do more if you want. Factory standard, they do 11.9v, rock steady, bulletproof, and clean.
"Big Fan" Switching models are the quietest, and, of course that fan can run off the 5v rail or you can just put an LED on the 5v rail. Without eating the hot air from a computer, the fan is potentially unnecessary, although the PSU enclosure isn't designed for convection (passive draft) cooling. So, without a fan, it would need a bottom intake and a top output for air.
The "Single Rails" supply is easier to manage than a "dual rails" supply, since all PC power supplies must have a load on all the rails. Fortunately, the Single Rail models (for office PC) are less expensive.
Other tips:
If there's several potentiometers (the aforementioned orange screw), then voltage is probably the one stuck out on a daughter card at a very weird angle (FC400 and larger).
A caution: The cause of death for a computer is usually the PSU sending out a dirty signal, so recycling from an expired computer isn't usually advisable.
Anywhere a hot wire goes, wrap a ground wire right along with it, even if it doesn't connect on the other end. Otherwise magnet chokes are good instead.
The extra price "decorative" and hippie (APFC) power supplies, both, usually make more noise, not less. At the extra price category, the Blue colored Fortron Source product is inferior to the plain unpainted version, so don't pay too much for any brand of "decorative" PSU because decorations subtract cost margin for what's inside.
A nice big capacitor, like 2200uf (right across the 12v line, neg to neg, pos to pos, just like a battery in paralell) can smooth the little voltage drops. That, I believe, is called a "smoothing" cap, and the benefit comes at a cost of creating a bit more "pop" when the amp is turned on.
A smoothing cap (as described above) even works on a wall-wart to keep the vocals from clipping when the bass hits hard; although, a wall-wart isn't going to keep up with classical or complex music that doesn't give it a "nap" so it can charge up that cap.
Maximum specs for the T-amp:
*maximum specs require heat sink and ventilation.
13.5 volts actual (13.2 on paper), conforming to automotive specs. At that rate, there needs to be additional load on the PSU in addition to the amplifier so that the voltage never peaks higher.
Reference load of 2 ohms this way*:
NOT two 4 ohm speakers per channel (reference load 1.5 ohms)
Three 8 ohm speakers per channel is fine (reference 2 ohms)
One 8 ohm and one 4 ohm per channel is fine (reference 2 ohms)
One DVC and one 8 ohm per channel is fine (reference 2 ohms)
Two 8 ohm speakers per channel is fine (reference 3 ohms)
One 4 ohm speaker per channel is fine (reference 3 ohms)
Crossovers:
Crossovers may purposefully contain shorting components, such as the textbook 2nd order crossover, and L-pads. These typical components sacrafice power to make nicer response curves of speaker drivers--they do increase load while decreasing dynamics.
A more ideal example for a small amplifier is a 1st order plus zobel and BSC, teamed up with a paper cone piezo that has a 50 ohm (reduces capacitive load) and 0.063uf cap (adjusts volume output) in series with it. Now, that is a light load indeed, although possibily needing heavy gauge inductors and/or an array / pipe enclosure.
Caps and listening fatigue:
Electrolytic input filter caps really do make more bass power. For sure 4.7uf electrolytic is more accurate on popular music, and a big effect for classical--more of a front row seat.
Believe it or not, a Nichion 4.7uf ($1) is a "can do" for big dynamics.
For those who don't want their house shaking, then 3.3uf electrolytic or 2.2uf poly can make less bass, with more power left over towards clean vocals.
Hey guys!
That's all I've found out so far.
My Sonic "T" is happily outputting about 20 watts per channel.
Unfortunately, my particular amp is unhappy with its volume control, so that it insists on either very loud playback or almost none.
Of course its the same amp with the big electrolytics, big PSU, tank cap, smoothing cap, and the reference load at max.
Its like Tim Allen on Home Improvement--Too Much Power. At least then you know when you have enough.
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