Aiyima A70 Mono - Leaked?

[Guddu]

Can anyone tell what is - Vircuit?

 

[Roland68]

I for one have two passive subs, repurposed from active ones. For a TPA3255 based sub amp, I am hoping to see more bulk capacitance than the usual 2x2200 uF most of these amps come with. Any comments on that @AIYIMA ?

Edit: only a tiny bit more it seems...
View attachment 391809

You remember that only switching power supplies are used and that larger capacities can be not only undesirable but also counterproductive.
Sometimes less is more. The Topping PA5 and PA5 II only have 1 x 2200uF. Here, quality is clearly more important than quantity.

What is interesting about your picture is that according to the Rubycon data sheet, JXF 3300uf 63v does not exist and is not listed anywhere. Two higher quality 1500uF 63V would make much more sense.

 

[MCH]

You remember that only switching power supplies are used and that larger capacities can be not only undesirable but also counterproductive.
Sometimes less is more. The Topping PA5 and PA5 II only have 1 x 2200uF. Here, quality is clearly more important than quantity.

What is interesting about your picture is that according to the Rubycon data sheet, JXF 3300uf 63v does not exist and is not listed anywhere. Two higher quality 1500uF 63V would make much more sense.

It is a recommendation of Texas Instruments themselves, surely depending on the power supply. And remember TPA3255EVM already comes with 2x4700uF:

 

[Corvuscorone]

Is the SPK Bass Cutoff Frequency Control knob on the left of the front panel an adjustable highpass filter for the main speakers?

 

[Guddu]

Is the SPK Bass Cutoff Frequency Control knob on the left of the front panel an adjustable highpass filter for the main speakers?

it seems like low pass filter when ampl is used as subwooder amp for passive sub.

 

[Corvuscorone]

it seems like low pass filter when ampl is used as subwooder amp for passive sub.

Why is it written SPK Bass Cutoff Frequency and not Sub Bass Cutoff Frequency? Doesn't SPK mean speaker? Or is it Sub Passive (K something) ? Maybe Aiyima could answer?

 

[Guddu]

Why is it written SPK Bass Cutoff Frequency and not Sub Bass Cutoff Frequency? Doesn't SPK mean speaker? Or is it Sub Passive (K something) ? Maybe Aiyima could answer?

May be description needs to be updated, but look at the left knob which says SW FREQ.

 

[Corvuscorone]

May be description needs to be updated, but look at the left knob which says SW FREQ.



View attachment 391980

You could be right, these devices often have confusing abbreviations.

 

[Guddu]

You could be right, these devices often have confusing abbreviations.

I actually confirmed it with Aiyima on FB, it’s exactly what I mentioned previously, a low pass filter knob only used when amplifier is set to subwoofer mode.

 

[doug s.]

What a strange product with a very limited potential market.

edit; it seems i was mistaken; these amps have no high pass cut-off. which is a shame. and ridiculous, honestly. a main benefit to using subs is that actively crossing over the main speakers will improve them and the amps driving them as well as giving you better bass.
disagree completely. with a pair of these, you can actively crossover your main speakers and your stereo subwoofers.

doug s.

 

[doug s.]

Depends on the subwoofer. My subwoofer has left and right inputs.

and if you plug l & r channels into them, you get summed mono bass.

doug s.

 

[doug s.]

Peculiar product. Bass management is much easier to do in the digital domain (steeper filters), where you immediately can add DSP. Here you need 2 monoblockw, with each having 2 (imprecise) pots for cutoff frequencies. It just complicates life...

it simplifies life for those who want an easy way to hi-pass their main speakers when using subs.
wrong - i was mistaken. this amp is sorely lacking because of this.

one of the main advantages of using subs is to hi-pass the main speakers so they and their amp(s) don't have to see the lowest frequencies. since many main speakers' woofers play into the midrange and low treble, hi-passing them will improve the sound.

bonehead move, aiyima - my system is actively quad-amped, but many listeners can't be bothered with active outboard x-overs - include them in these amps!!!

doug s.

 

[doug s.]

@AIYIMA How does the sub-out implementation works? The sub will be getting only the right or left channel input? To me doesn't make a lot of sense to put a sub out on a monoblock amp.

many people run stereo subs. this makes a whole lot of sense to me.

what makes no sense to me is not including a hi-pass option w/variable x-over for the main speakers.

doug s,

 

[terryforsythe]

and if you plug l & r channels into them, you get summed mono bass.

Of course. Why is that a problem?

Edit: It is not a problem. Are two subwoofers better than one? Yes, but not because of stereo, it is because using more subwoofers, strategically placed in the room, is better for room correction. Actually, three work better than two.

But, if you are like me and only have space for a single subwoofer, summing the left and right channels is the way to go. The wavelengths are so long that I cannot detect where the subwoofer is located when listening to music. It all sounds like it is in the sound stage created by the speakers.

 

[doug s.]

Of course. Why is that a problem?

Edit: It is not a problem. Are two subwoofers better than one? Yes, but not because of stereo, it is because using more subwoofers, strategically placed in the room, is better for room correction. Actually, three work better than two.

But, if you are like me and only have space for a single subwoofer, summing the left and right channels is the way to go. The wavelengths are so long that I cannot detect where the subwoofer is located when listening to music. It all sounds like it is in the sound stage created by the speakers.

my experience has been that, when subs are set up for stereo, there's an improvement in the soundstaging. it's recording dependent, but you can definitely hear it on some recordings. best mono sub placement i've heard is when the sub is directly centered between the speakers, and in the nearfield - ie: where your feet are, or directly behind the listening area. definitely not always conducive to good room aesthetics, tho. it might work if you can roll your sub into the nearfield when listening; otherwise have it out of the way.

doug s.

 

[terryforsythe]

but you can definitely hear it on some recordings

Probably the crossover slope is not steep enough, the crossover frequency is too high, and/or the subwoofer has too much harmonic distortion.

I have played thousands of recordings with my subwoofer. I never have been able to pinpoint its location in the music. I use 48 dB crossover slopes and its harmonic distortion is very low (Velodyne HGS-18).

 

[doug s.]

Probably the crossover slope is not steep enough, the crossover frequency is too high, and/or the subwoofer has too much harmonic distortion.

I have played thousands of recordings with my subwoofer. I never have been able to pinpoint its location in the music. I use 48 dB crossover slopes and its harmonic distortion is very low (Velodyne HGS-18).

24db/octave is a steep enough slope. no, i cannot locate the subs, but the soundstaging itself is wider when the subs are stereo.

i'm presently at 60hz x-over, i've gone as high as 80. (once for a pair of speakers i was auditioning for a friend, i went to 125, because the speakers had such a bass bump, it was cleaner thru the subs.) my subs, btw are -3db at 17hz, and will do 115db at 20hz with <2.5% distortion.

ymmv,

doug s.

 

[GXAlan]

All of the JBL Synthesis subwoofers are passive, so there are high end subwoofers that are passive. That said, in those cases, you need a lot of DSP at which point the front knob is useless.

I guess with DACs all hitting 120 dB, companies are trying to sell amps.

 

[Ropeburn]

An adjustable highpass for its speaker output would've made a lot more sense. That is what's missing on the market the most. And who needs a lowpass for active subwoofers? I never understood that.

 

[Guddu]

Promotional discount code for Aiyima A70 Mono:

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