Can you explain why some of the amps I have listened too in the past. Had have a very flat response, they also had a skinny bass. While less then flat response amps, resulted in better bass. And the rise in the freq was not in the low FR range either.
Please reference (links) a physics journal or study that supports your claim that audio amps that have ruler flat response result in correct bass, great bass, or low freq bass that will slap you totally nonsense.
Please reference (links) a physics journal or study that supports your claim that audio amps that have ruler flat response result in correct bass, great bass, or low freq bass that will slap you totally nonsense.
My experience is that if you are used to muddy bass (high THD, high IMD, poor PSRR) precise bass will sound lacking at first. Listen for a bit and you will be amazed by the amount of detail in the bass. This applies to the Modulus-86 as well.
The Modulus-86 has extremely low THD, extremely low IMD, and very high power supply rejection (PSRR). This means it's as close to a straight wire with gain as you can get. If precision is what you want, the Modulus-86 is for you.
No. A quick glance on the NE5534 data sheet also reveals that if you do rework the compensation to make the NE5534 work with the MOD86, you'll degrade the performance by at least 20 dB across all parameters that you'd care about.
I do know someone who recently sold his Modulus-86 Rev. 1.0. The day after he sold his completed boards, he purchased a set of Modulus-86 Rev. 2.1 board from me.
Exactly.
Tom
I put four channels of MOD86 in a BZ4309 (eBay) enclosure along with an Antek AS-3222 and a Power-86 board. The internal dimensions of the chassis are 330 x 84 x 274 mm. The input cabling for two of the channels run along the rear panel within about 1 cm of the transformer, across the IEC inlet to the two amp boards. The amp boards themselves are probably 3-4 cm from the transformer. In other words, while I did use microphone cable on the inputs, I didn't do anything special in my build.
I've built two amps like that. Both have residual mains hum below -110 dBV for the worst offending mains component. -110 dBV is 3.2 uV.
To summarize: I wouldn't worry about mu-metal. Just try to minimize the wire lengths and keep the wiring away from the transformer to the extent possible. The supply connections are slightly more sensitive than the output connections, so try to minimize the supply wiring first. Then the output wiring.
The MOD86 has a differential input, hence is much less sensitive to hum injection on the input cabling. In addition, the layout of the MOD86 board was optimized to keep the sensitive nodes as compact as possible and the loop areas as small as possible. The board itself is not very sensitive to hum injection. On top, the loop gain of the MOD86 exceeds 200 dB at 60 Hz, so any hum that does somehow manage to get into the circuit is attenuated by 200 dB. That's a lot!
Tom
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You can show me all the graphs in the world but if it doesn't sound right to my ears then I'm not interested.
I have a budget Cambridge Audio AM1 that uses the LM4766T chip. This amp is my only experience with chip amps and is the reason for searching for a better chip amp design. The AM1 doesn't lack bass but it does lack a bit of high frequency detail compared to one of my other amps.
Well, I've sent someone a PM who lives near me and happens to have a Mod86. Hopefully he'll agree to compare my AM1 to his Mod86.
The perceived sound quality is important. Thankfully, there is an overwhelming body of research which shows good correlation between good measurements (plural) and good perceived sound quality. This means we can rely on objective measurements rather than subjective opinion when selecting between circuits and equipment.
Cool!
Tom
That would be me
You're more than welcome to come round - replied to your pm. As to lacking bass, nonsense - clean, tuneful and deep when required with no overhang, that's how I'd describe it.I'll dig out the Massive Attack!
That would be me
I'll dig out the Massive Attack!
It looks like we may have a problem connecting your source to the RCA inputs on my amp. Am I right in thinking I'd need a couple of XLR male to RCA Male adapters? LINK
Absolutely no need to apologise. That is the whole reason I started this thread over a year ago, when I thought I might get my boards finished... Our goal is to help get boards working.
At risk of straying off the beaten track, there are a number of things that can happen with speaker interactions as well as perceptions. Tom has covered the fact that high THD can 'fill out' the bass subjectively, but there is also the fact that some speakers, particularly full ranges like fostex have an impedance that goes up to 100Ohms or more around Fs. For these a low damping factor actually does improve low end which is why people love them with valve amps.
At the other end there are some high end monsters that have very low impedance dips and in that case you need a welding grade amp, or better speakers.
It's a complex science, but science nonetheless.
Strongly agree on both points (at least from a subjective standpoint), and yes Unklejoe's coil winding is awesome!
Post 1557 for those interested. I would love to know what his technique is
.Best,
Anand.
Having built nearly 20 boards by now, I'm getting half decent at the coil winding. I find it helps if you start with a piece of wire that is free of kinks and bends. By far the easiest is if you can avoid bending it as it comes off the spool. Should you get a bend in the wire, you can often straighten it out by running it across the coil former a few times. Then "just" wind slowly, taking care not to create another bend in the wire.
I generally find that the first few turns are the hardest to make but the last turns go on easily. I usually start with about 1 m of wire and end up with some 17-18 turns. I then un-wind the ugly turns to end up with 15 turns total. The end result is pretty good as can be seen in Post #1555, though not at the levels of Unklejoe.
Tom
I generally find that the first few turns are the hardest to make but the last turns go on easily. I usually start with about 1 m of wire and end up with some 17-18 turns. I then un-wind the ugly turns to end up with 15 turns total. The end result is pretty good as can be seen in Post #1555, though not at the levels of Unklejoe.
Tom
Thanks for the compliments everyone!
For my coils, I cut off one end of my Dad's half inch socket extension and used that as a former
He wasn't thrilled, but it was a necessary sacrifice lol
It ended up working fairly well because the big end of the socket has a hole in it which can be used to feed the wire through for the initial turns. This allows me to put a decent amount of tension on the wire as I'm turning it.
For my coils, I cut off one end of my Dad's half inch socket extension and used that as a former
He wasn't thrilled, but it was a necessary sacrifice lol
It ended up working fairly well because the big end of the socket has a hole in it which can be used to feed the wire through for the initial turns. This allows me to put a decent amount of tension on the wire as I'm turning it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
It would have been nice to have one of these handy. I'd bet a HAM radio friend probably has one laying around.
Ceramic Coil Form Ribbed with Holes 1 15 16" L x 1 2" Dia Hard to Find Item | eBay
An externally hosted image should be here but it was not working when we last tested it.
Ceramic Coil Form Ribbed with Holes 1 15 16" L x 1 2" Dia Hard to Find Item | eBay
Thanks for the compliments everyone!
For my coils, I cut off one end of my Dad's half inch socket extension and used that as a former
Your dad will get over the loss, I'm sure... The sacrifice was worth it.
I do wonder if it's necessary to lob the end off, though. The square end of the extension isn't larger than the diameter of the middle portion. Also the wire does tend to spring back a little, so you should have some amount of wiggle room to work with.
Neat idea, though. I'll try that next time I need to wind one of those inductors.
Tom