Looking in to matching my DAC & MAOP 10.2 Mar-kens with an amp.
Dac: https://www.amazon.com.au/gp/product/B09H4G2XDJ/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
I have a Class D Audio CDA-254L amplifier kit which has a 10k input impedance and volt gain set to 35. Which I could use, or at least I could use it's toroidal power supply (up to 55V) to power a new amplifier board.
I know very little about impedance matching etc, and am not even sure what the output impedance on the DAC RCA outputs are. I've tried googling the chipsets in the DAC and haven't been able to figure it out (learnt some more about the parts though
). Any suggestions?
Cheers!
Dac: https://www.amazon.com.au/gp/product/B09H4G2XDJ/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
I have a Class D Audio CDA-254L amplifier kit which has a 10k input impedance and volt gain set to 35. Which I could use, or at least I could use it's toroidal power supply (up to 55V) to power a new amplifier board.
I know very little about impedance matching etc, and am not even sure what the output impedance on the DAC RCA outputs are. I've tried googling the chipsets in the DAC and haven't been able to figure it out (learnt some more about the parts though
). Any suggestions?Cheers!
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Hello! I have a question. I have been trying to figure out on WinISD how to calculate this sort of thing, but I am still learning the ropes when it comes to simulation software... And now my laptop has died! And I'm getting antsy haha
So, my question. I know the Alpair 7MS is not renowned for its SPL capabilities, but if I were to cross this driver with at least a second order XO at ~500Hz, would it be capable of producing fairly high volumes in a sealed enclosure ~.8 QTC? Thank you! I am trying to learn how to do this stuff by myself but there is so much to learn and I am focusing on other stuff right now.
So, my question. I know the Alpair 7MS is not renowned for its SPL capabilities, but if I were to cross this driver with at least a second order XO at ~500Hz, would it be capable of producing fairly high volumes in a sealed enclosure ~.8 QTC? Thank you! I am trying to learn how to do this stuff by myself but there is so much to learn and I am focusing on other stuff right now.
This is not excursion but I just happened to have Xsim fired up and this should be relevant enough. You can see from the theoretical power dissipation (of the driver) that if anything in the lower hundreds of Hertz and below that previously would have overdriven it would now have to be many times higher (in volume setting) to do so.
Most small (3-5") full-range drivers will be limited in the physical and thermal power they can handle.
Typical specifications read something like Power 20W, Linear X +/- 5mm, Cone area 50cm2, Sensitivity 87db/1W/1m.
With these limitations, the driver would be hard-pressed to hit 100db even with a High Pass at 250-300Hz. A maximum SPL of 95db is more realistic, even assuming the full range has a helper woofer below 300Hz.
I, too, am sceptical of using full range-based systems for loud rock music or home theatre.
Won't the thermal limits of the voice coil limit SPL as well?
The MAOP 7, I think, can handle 20W. The Tang band drivers can handle 12W and 25W, respectively.
https://www.parts-express.com/Tang-Band-W3-1878-3-Full-Range-Driver-264-902
https://www.parts-express.com/Tang-Band-W4-1879-4-Full-Range-Driver-264-903
At least on paper, I like these 2 Tang bands too.
Sure, I don't get that loud often nowadays. I did measure 130+db with an old Radio Shack analogue SPL meter for a short time when I had JBL B460 (2245J based) bass bins doing bass duty (one per channel). The Midbass was managed by a pair of Focal 8N515 (per channel). I had ear protection on, and it was still loud.
A 4x12 Marshall Stack with a 100W JCM 800 (2203) can make 110+db if you aren't too far from it.
That and xmas. Latter likely not an issue given the significant excursion of MAs.
But given the transient energy of music, and the fact that so much of the range is not being done by the A7ms. Something lke 5 octaves instead of the 9+ they are capable of in the right box. The woofers are doing most of the work.
dave
My PA may have played that loud. Of my own design, used 4 x Bryston 4B, 2 x Bryston 3B, and 2 QUAD 303s to drive it and they were never far from clipping.
4 15” horn louded bass drivers/side (say 50 Hz extension).
dave
You owned some of my "dream" amps. I dreamt of having Bryston 0.4B 4B Pre-Power amps and the Quad 303-405 combo. Sadly I could only afford Adcoms (535 and 555), Carvers (M1.0t and 4.0t) and a B&K ST140.
The stages were a lot smaller, and we were cramped for space. I tried to stay as far away from the drummer's kick drums as possible.Lots of old guys here that played in rock bands, who are now pretty much deaf as posts.
My wife sometimes threatens to sell my stash of guitars when I misbehave.
Sidebar question, how do mark audio drivers generally behave when you throw loads of power behind them. I have the Hypex NC500's on some Alpair 7's. I don't really ever listen loud, but do enjoy the 'grip' I feel these amps give, the speakers see more like 250w into 8ohms. I always liked the idea of headroom (until my Roon server updated and defaulted to full volume and crumpled the cones).
I might repurpose these amps for another project (subwoofer). Is it wasted money and power having more than 100w on these or is there a benefit to more power even if you are not driving it hard?
I might repurpose these amps for another project (subwoofer). Is it wasted money and power having more than 100w on these or is there a benefit to more power even if you are not driving it hard?
As long as you make sure not to exceed their mechanical max excursion limits, you should be mostly fine.
Exceeding their electrical limits and frying the coils is harder unless you are asking them to play full range down below 100-200 hz or so
I had similar experience with wide-band (aka full-range) drive units and Hypex UcD - the amp seems to have a good grip on the drivers; this is not only due to the power headroom, but also due to lower output impedance of the amplifier, which is also expressed as higher "damping factor".
Sorry to hear about your accident with the drivers - do you have any images of the crumpled cones? How do the speakers sound now?
They are running true full range, but they are never played very loud. I use the NAD's XO to cut below 60Hz for movies and Apple TV has a really nice 'reduce loud sounds' setting as the dynamic swings in some modern movies is huge.
For reference the NAD amp can run in % or DB, in percentage its never higher that 45% for tv/movies and 30% for music from Roon server. I think I will get the NC252 though as 250w (125 into 8) I'm sure would be sufficient, and the 500w modules can power a subwoofer.
They still sound fine, it only went crazy loud for a split second before I could turn off the amp. Someone clever could probably tell me the Hz that caused the star crumpling around the edge.
I have a new boxed replacement set of Alpair 7.3's to replace at somepoint soon.
For reference the NAD amp can run in % or DB, in percentage its never higher that 45% for tv/movies and 30% for music from Roon server. I think I will get the NC252 though as 250w (125 into 8) I'm sure would be sufficient, and the 500w modules can power a subwoofer.
They still sound fine, it only went crazy loud for a split second before I could turn off the amp. Someone clever could probably tell me the Hz that caused the star crumpling around the edge.
I have a new boxed replacement set of Alpair 7.3's to replace at somepoint soon.