Truepath TA3020

[v-bro]

I am not promoting anything, I am only giving positive or negative criticism.

If I would have been so far off then all my criticism should have left you cold. Same goes for a few others...

[Artcore87]

Old thread, I know, but I'll add my experience since this thead will still be read by others, just like I read it for myself just now.

I own the Connex v3c, and his a350smps. He was very helpful and nice towards me and answered the questions I had, and also provided me the amp customized exactly like I wanted it. On his order page, there are drop down boxes to choose certain different components, and on my v3c I chose to select all of the best/most expensive upgrades available, which included better better mosfets, bigger caps, and a couple other minor things. Besides these drop down boxes though, he also set the voltage for the SMPS to my request. Beyond this he did something for me that I did not even ask him to do nor did I have any idea it needed to be done, and he didn't even tell me he did it. Since he knew I'd be using an SMPS, he removed the rectifier bridge that normally comes on his boards in case you plan on using a transformer. I was unaware of this but he sent me an amp that had already been fixed and made ideal in this respect.

Now, subjectively, the sound and quality of this amp is amazing. I have heard 41hz offerings, and from memory I cannot tell a difference in quality, only that the 41hz amp (amp6) was not nearly as powerful and so they are incomparable as I turn up the volume control. I can say that for me, the gain setting is just fine. If anything it is too high, not too low, but this is perfect due to how I control the input volume.

While setting things up and experimenting I have shorted out the power supply while it was hooked up to the board and both still work perfectly. I have shorted ac inputs on the 3020 board with the speaker outputs (accidentally obviously), still with no permanent consequences. So the stuff seems very reliable. Even with only the 350w smps, and driving 15" 400w JBL woofers, I cannot find the power limits of this amp. It can sound clean until it blows my speakers.

I'm much more impressed with the sound quality than I am the power, even though the power is very impressive. At medium and low volumes, the sound is amazing. In my application there is currently definitely some unwanted noise, and that is my fault not his amps fault. I do not have the amp in a proper case and I do not have the input cables properly shielded etc. Grounding of amp and smps, as well as wires/connections/interconnects and shielding could all be improved by me (and will be eventually) to lower the noisefloor, but even with my sloppy implementation, the amp is STILL actually very quiet! On top of the woofers I've got sensitive midrange horns, and then ribbon tweeters... so my speakers are definitely of the very sensitive type which show me all the unwanted noise of the amp... and let me tell you it is quiet. I have no volume control or resistance whatsoever in front of the amplifier, so it is constantly amplifying at full gain ever parasitic noise that occurs prior to it... from my sound card (gadget labs wave 8/24) and my cables... given this setup the noisefloor is being maximized, i'm purposely amplifiying all parasitic noise by choosing to control the volume via software in my computer, and simply lowering the output of my sound card to control volume.... the noise floor stays the same and is amplified, while the music signal is lowered.

It would seem that this would only be acceptable at higher volume levels, to get a good s/n ratio... but that's not the case. Due to the quality of the gadget labs wave 8/24 and how quiet it is, this setup is perfectly usable even at low volumes (though not ideal, I realize this). My computer itself makes more noise than the amplifier does while amplifying all this parasitic noise with no resistance in between.

Keep in mind this is not how I want to have my system set up ideally. Eventually I will go with something like a stepped attenuator or an LDR or something else of that quality as my volume control RIGHT in front of the amps input (within inches), and then I will use that to control the volume, but only after choosing first the optimum output volume for my sound card to achieve it's own best performance and s/n ratio and dynamic range... and then once that is determined, the volume control in front of the amp will be used, since it's performance will be nearly exactly the same regardless of what range I'm using it in. Also the output of the gadget labs is widely adjustable.

I use foobar for music playback, and can use ASIO, KS, DS, or WASAPI (currently I believe ASIO to be the best, but in fact this is debatable as evidenced by forum discussions on head-fi). Here are some specs regarding my source:

Gadget Labs Wave 8/24:
ANALOG AUDIO OUTPUT

---Drive level: +4dBu or -10dBv, auto-switched via software.

(I use -10dBv, because it is still insanely loud due to the ta3020's gain. using this soundcard I have no master volume for windows, each application must have it's volume lowered to not blow out my eardrums and windows. in Foobar I can do this very accurately with an awesome dsp plugin that offers digital volume attenuation that is near perfect, certainly better than any potentiometer, but if i'm watching a movie with VLC I have to set its volume to between 3 and 8 percent to be acceptable... and this is at -10dBv, I could go to +4 if I found that the gadget labs performed better this way, and compensate with a stepped attenuator in front of the amp (for example)


output impedance: 100 ohms
connections: 1/4" jacks and XLR connectors via patch box
SAMPLING CONVERSION

Analog-to-digital converters

24-bit, 128-times over-sampling
sampling rates (kHz): 11.025, 16.0, 22.05, 24.0, 32.0, 44.1, 48.0
dynamic range: 105 dB, A-weighted
digital-to-analog converters

24-bit, 128-times over-sampling
dynamic range: 106 dB, A-weighted
frequency response: 10 to 20 kHz, +-0.1 dB


Now here are the ta3020 specs. It is interesting to note that many of them correlate quite nicely with the Gadget Labs, namely snr, channel separation, and dynamic range (which is ~102d each I believe, even though the ADC/DAC of the card exceed this). Also since most of my source material is 16 bit, and the card runs native in 24, either dithering is used to run at 16 bit, or over/upsampling is used to run at 24 bit. I haven't determined which is better. For equalization I use one of two DSP/VST plugins with foobar, which offer extreme accuracy, being better than any analog type EQ.


ta3020 tech specs:
Min Typ Max
Output Power (4R) 190W 220W -
Output Power (8R) 100W 120W -
Bandwidth 20kHz -
Signal to Noise ratio -102dB -
THD+N@50W 0.02% -
Intermodulation Distortion - 0.03% -
Channel Separation 97dB -
Switching Frequency 200kHz - 1.5MHz
Supply Voltage 1 +/-15V +/-45V +/-65V
Quiescent Current 1 - 90mA -
Supply Voltage 2 +4.5V +5.0V +5.5V
Quiescent Current 2 - 45mA -
Supply Voltage 3 +9V +10V +12V
Quiescent Current 3 - 200mA -

[Richie B]

Cristi does indeed provide fantastic customer service. I also have experienced this. It's a rare and priceless quality in the generally negative consumer market we have unfortunately all grown accustomed to.

[Cristi]

The Beat goes ON Connexelectronic

[Artcore87]

Originally Posted by Cristi

The Beat goes ON Connexelectronic

Cristi, I was in an electronics store recently and had the opportunity to purchase a stepped attenuator but I do not know the specs required for my application.

What should the specs of the stepped attenuator be if I am using it directly in front of the amps input as a volume control?

Does the v3c have preference as to what I feed it? I mean... I know it must. I guess my question is what is it's preference. I'm feeding it with a -10dBv signal from my gadget labs wave 8/24, and controlling gain via dsp in foobar... -18dB in this foobar DSP gives me VERY loud volumes... I usually run between negative 50-60db (very quiet) to -24db (rather loud but not even close to distorting my speakers).

What should the ideal output impedance of my soundcard be? I believe the output impedance is 100 ohms. Can a stepped attenuator itself correct for this and present a different output impedance to the amp?

Thankyou!