I have the 27V meanwell running at 32V. I used my amp to power some ELT525 monitors during my new years party at pretty loud levels. It was on from about 7pm in the afternoon to 3am. I was pretty drunk but i do remember placing my hand on the power supply when i unplugged it and it was only warm. The fan wasn't even on.
Hi all,
I'm purchased two of these amps to power my mid-range and tweeters in a tri-amp setup. The mid will be hi-passed @ about 900Hz so I'm not too concerned with lower freq. resolution... Are most of these mods implemented to improve the bass response of this amp, or are there any *simple* modifications that you can recommend to sweeten up the mid/top end?
I'm horrible with a soldering iron but I'm working on it)
Thanks
The input caps and output coils are the most bang for the buck. They affect the whole range. Power supply mods help the bass more than mids and highs.
If you're high-passing above 100 Hz, you can use smaller input caps. The .47 uF Dayton polypropylene/foil (not polypropylene/film) from Parts Express will work superbly and are as good as anything you can get under $100.
-dr_vega
I took one of my Sure 2*100w amps to a local audiophile meeting Sunday. It is modded with West Cap 2uF paper-in-oil input caps bypassed with .47uF Dayton poly/foil caps. It also has air-core inductors with paper and tin foil shields. Two Panasonic FM 620uF tank caps bolster the power supply. The board is driven by a 36v 3 amp Kodak smps brick from a laser printer.
Three of the people at the meeting have high end tube amps. One of them "hates solid state amps, especially digital amps." The other person is tri-amped with Adcom solid state amps.
After several hours of listening to all kinds of music, all of them agreed that the modified Sure was better than the high end amps they had at home. Even the guy who couldn't stand digital amps conceded that the Sure was as smooth as, and more detailed than, his Rogue Audio tube amp.
This was not a scientific double-blind test. It wasn't even an A/B comparison. It was just some guys who love high quality sound being knocked out by a little amp that cost less than $100 including the power supply and mods.
-dr_vega
Three of the people at the meeting have high end tube amps. One of them "hates solid state amps, especially digital amps." The other person is tri-amped with Adcom solid state amps.
After several hours of listening to all kinds of music, all of them agreed that the modified Sure was better than the high end amps they had at home. Even the guy who couldn't stand digital amps conceded that the Sure was as smooth as, and more detailed than, his Rogue Audio tube amp.
This was not a scientific double-blind test. It wasn't even an A/B comparison. It was just some guys who love high quality sound being knocked out by a little amp that cost less than $100 including the power supply and mods.
-dr_vega
It sounds fine, better than the stock coils, but the air-cores sound much better. I'm now running 10uH air-cores with the stock caps.
-dr_vega
Thanks for the info, Joe / Scott / Dr. Vega.
Joe, I've been wondering about the passive (line-level) filters... Is the x-over frequency dependent on the impedance of the amp's input? Are you building your own filters?
I'm already running a DCX with my existing speakers, but it'd be cool doing some active 2-ways with passive in-line filters
Joe, I've been wondering about the passive (line-level) filters... Is the x-over frequency dependent on the impedance of the amp's input? Are you building your own filters?
I'm already running a DCX with my existing speakers, but it'd be cool doing some active 2-ways with passive in-line filters
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Pelayostyle,
sounds like some rigorous testing I appriciate your scientific approach to this
thanks for the infoDarpMalone
like I mentioned I don't have anything up and running, PLLXO's seem to have a lot going for them if you don't mind the limitations that go along with them (they are limited to low order crossovers, and are affected by the amps input impedence). You can read more about them here.
Dr. Vega,
that is a good story. I already gave up my tube amp in favor of an 41hz amp3. I'm looking forward to hearing what this Sure amp has to offer. Your story makes me that much more anxious to get the amps up and running.
Joe
I thought about doing that, using the Sure's input caps as the hi-pass filter and the output coils as the low-pass filter. In fact I am using input caps that could act as filters, but I'm using active filters which have steeper curves than the simple one-cap filters. I'm using .47uH on my midranges and .01uF on my tweeters.
I didn't try low-pass filters on the output coils because the inductance values are very large. Still, it is possible and if you are duplicating the filters in the speaker crossovers, it makes some good sense to get rid of one set of filters.
-dr_vega
Dr. Vega,
that's very interesting to hear about. I was just planning on implementing a standard passive line level crossover. I had thought about using a smaller input caps as a high pass filter, but then I read some where on this thread about how much the smaller input capacitors effect the phase, but maybe not anymore than a standard 1st order crossover? Right now I have my speakers crossed at 300Hz. A first order on the 4" full range driver, and third order on the 12" driver. Are you saying I could use a larger output inductor as one of the poles on this third order crossover? That could be very good. I was thinking about trying a second order PLLXO on the 12" driver and then a single inductor for after the amp to act as the third pole on the crossover (as PLLXO don't seem to be well suited for anything above 2cnd order). How would I go about calculating the values for the capacitor and inductor?
thanks
Joe
that's very interesting to hear about. I was just planning on implementing a standard passive line level crossover. I had thought about using a smaller input caps as a high pass filter, but then I read some where on this thread about how much the smaller input capacitors effect the phase, but maybe not anymore than a standard 1st order crossover? Right now I have my speakers crossed at 300Hz. A first order on the 4" full range driver, and third order on the 12" driver. Are you saying I could use a larger output inductor as one of the poles on this third order crossover? That could be very good. I was thinking about trying a second order PLLXO on the 12" driver and then a single inductor for after the amp to act as the third pole on the crossover (as PLLXO don't seem to be well suited for anything above 2cnd order). How would I go about calculating the values for the capacitor and inductor?
thanks
Joe
It's certainly an intriquing idea. Since the Tripath amps have a high pass filter on the input and a low pass filter on the output, why not calibrate them to act as the speaker crossover and eliminate redundant filters.
The formulae for the filters are in the Tripath datasheet for the TK2050. It's not as simple as it might seem. The frequency of the input filter is affected by the input and feedback resisters and the output filter needs to consider ringing and back emf spikes and things like that. This is a lot more than picking a cap and a coil.
Still, it's an interesting project. If you have the skill, the test equipment and can afford to risk blowing up an amp or two, I hope you try it and let us know how it works out.
-dr_vega
Passive line level crossovers would be an interesting project, but I have to ask, other than the fun of making them, why would you want to do it? A Behringer DCX2496 costs $300. Good quality parts for a stereo three-way passive crossover would cost that much, or more.
I think you'd be much better off getting your fun from modding a DCX. In addition to a great sounding, extremely flexible crossover, you'll get parametric equalization, time alignment, and phase control.
-dr_vega
Hmm....
Well I finished these speakers two years ago or so... and I'm quite proud of them. The 4" fostex driver is quite nice and handles everything down to 300hz, which also happens to be where the baffle step compensation is needed. Below that I have a 12" Eminence driver. I feel as though a PLLXO would be the the cheapest way for me to improve the sound. The 4" driver only has a single cap between it and the amp, which would be quite easy and cheap to move in between the amp and the preamp since I'll have two quality amps after I finish up the Sure amps. The 12" driver has a l-pad (for adjusting the baffle step compensation) and a third order crossover on it. Certainly it will be easy to remove the l-pad and put in a high quality attenuator before the amp. As for the third order crossover? I don't know. Panomaniac, I doubt I'm clever enough to figure out a third order crossover. Really from what Dr. Vega says I doubt I'm clever enough to figure any of it out. I'll probably just stick with a standard second order PLLXO in front of the bass amp and then take care of the last pole after the amp.
Anyways all of this is pretty much saying, I think I can improve things pretty significantly for less than $30 for the PLLXO parts. $300 is pretty far out of my budget right now, as much fun as it does sound to be able to just sit there and experiment with different crossover slopes and points. Maybe at some point I can get one, but for now I'm happy to be able to get the two Sure amps. I'm all ears though if people have other suggestions as to different ways to handle the crossovers(though maybe this is the wrong forum to be asking this in).
Joe
Well I finished these speakers two years ago or so... and I'm quite proud of them. The 4" fostex driver is quite nice and handles everything down to 300hz, which also happens to be where the baffle step compensation is needed. Below that I have a 12" Eminence driver. I feel as though a PLLXO would be the the cheapest way for me to improve the sound. The 4" driver only has a single cap between it and the amp, which would be quite easy and cheap to move in between the amp and the preamp since I'll have two quality amps after I finish up the Sure amps. The 12" driver has a l-pad (for adjusting the baffle step compensation) and a third order crossover on it. Certainly it will be easy to remove the l-pad and put in a high quality attenuator before the amp. As for the third order crossover? I don't know. Panomaniac, I doubt I'm clever enough to figure out a third order crossover. Really from what Dr. Vega says I doubt I'm clever enough to figure any of it out. I'll probably just stick with a standard second order PLLXO in front of the bass amp and then take care of the last pole after the amp.
Anyways all of this is pretty much saying, I think I can improve things pretty significantly for less than $30 for the PLLXO parts. $300 is pretty far out of my budget right now, as much fun as it does sound to be able to just sit there and experiment with different crossover slopes and points. Maybe at some point I can get one, but for now I'm happy to be able to get the two Sure amps. I'm all ears though if people have other suggestions as to different ways to handle the crossovers(though maybe this is the wrong forum to be asking this in).
Joe
I also ordered the 2*100W 4Ω amp from sure. Hooked it up quickly and worked flawlessly. Definately an improvement to a diy amp i used from the 70's. So i decided to built it in a nice enclosure, which worked for a day, but as i was fiddling (quite heavy handed i must admit) with the pot meter to put a knob on it stopped working
No fan nor leds. I took everything apart, hooked up a lab power supply and it seems shorted. Between 0-10V I i see some current being drawn (.5A) , but once over 10V it gets shorted.
Has anybody got a clue where the problem might be? I don't see a loose solder connection. Or do you think the chip(s) got fried? But how could this be by a little shaking?
No fan nor leds. I took everything apart, hooked up a lab power supply and it seems shorted. Between 0-10V I i see some current being drawn (.5A) , but once over 10V it gets shorted.
Has anybody got a clue where the problem might be? I don't see a loose solder connection. Or do you think the chip(s) got fried? But how could this be by a little shaking?
Hey Joe - there is a ton of good info on the web about low and high pass filters built around opamps. IIRC, TI has some nice stuff in their application notes. Linkwitz also has good info on his site.
Just have a look at that stuff. You should be able to find a 3rd order filter with 1 opamp.
Parts count will be pretty low.
If you find something, just ask questions about it here.
Just have a look at that stuff. You should be able to find a 3rd order filter with 1 opamp.
Parts count will be pretty low.
If you find something, just ask questions about it here.
Hey all,
I finally got around to assembling my SureE amp with a 27v Meanwell PS in an enclosure last night. I had it sitting on top of my entertainment unit for most of the day today and I've been listening to music at a moderate level (there's no lid covering the case at this time and nothing's obstructing the board or the power supply)... The PS is warm to the touch but the fan turns on quite frequently, even if I'm only watching TV. I'm only powering mids & tweets so I'm surprised that it's coming on @ all. Is this normal? It's a bit loud for my taste
I finally got around to assembling my SureE amp with a 27v Meanwell PS in an enclosure last night. I had it sitting on top of my entertainment unit for most of the day today and I've been listening to music at a moderate level (there's no lid covering the case at this time and nothing's obstructing the board or the power supply)... The PS is warm to the touch but the fan turns on quite frequently, even if I'm only watching TV. I'm only powering mids & tweets so I'm surprised that it's coming on @ all. Is this normal? It's a bit loud for my taste
My power supply fans never run
I've been blasting my amps into inefficient but powerful Usher two ways with MeanWell S-102-36v supplies set at 32v at beyond sane levels for months while I evaluate mods and have never had the ps fan turn on with either one of my supplies. Is the amp heatsink hot? My supplies get just warm to the touch and the amp heat sink feels a little cooler still.
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