That can be installed to a t-amp by putting a fast/softswitch silicon diode parallel with a 1 ohm resistor in series (into) the V+ line. Looks like a diode voltage drop parallel with a resistor. Tip: Check function with the diode drop alone before adding the resistor onto the diode (procedure assures intended polarity).
That "D||R series to V+" makes "constrained crc" but with the problem of the resistor and diode at different speed so that the higher resistor values, such as 1R make a slight euphonic effect. Look again and see that it is a miniature reverb.
Whatever caps exist either side of the D||R will vary the effect. Do you see the funny thing about this device? It removes disharmonic noise like a regular CRC, it has less sag than a regular CRC, but that comes at the cost of installing a miniature reverb. lolz! I kind of like it though. A CRC that doesn't sag as much, also doesn't hurt so bad at the wallet when buying transformers.
Is more desirable signal a more efficient output or is it distortion? Maybe it is both? I can't decide that for you. Anyway, enjoy the miniature effects box.
They don't all do that. There is a very broad range of performance.
For warmth, width, and no extraneous preamp:
MyRef monoblocs 45w~50w per channel
LM1875 monoblocs 24w~27w per channel
Parallel LM1875 monoblocs 45w~50w per channel
Those are the easy way to get what you're asking for, since your requests are well within the range of possible settings of those amplifiers.
um, you've NEVER argued with a dozen fools at once that refuse to admit that ported speakers are more distorted than acoustic suspension ones which DON'T add RESONANT harmonics not present in the actual signal no matter how many different technical sources you site, how you TRY to get them to see that ported speakers are the same exact thing as blowing on a bottle hole, or how the air space causes a delayed sound wave that needs to take a longer path to reach the listeners ears as well as longer to dissipate or even use an actual speaker manufacturer's pros and cons that agree with the truth you learned the FIRST time you ever heard an acoustic suspension minimonitor before knowing the technical reasons WHY it's bass, though smaller, is so much quicker and more detailed.
i wouldn't be surprised that repeating these TRUTHS gets someone else's panties in a bind.
if someone loves a particular form of distortion, they'll refuse to admit it and get quite an attitude about challenging their flawed assumptions. you give people too much credit.
i learned very long ago, facts mean nothing in the eyes of most people, just whatever the reptile at the base of their brain is grunting.
i have no problem with people preferring the bigger weightier bass that ports add as long as they admit it's a euphonic distortion. i REALLY wish someone would do a waterfall plot and distortion measurement for the same driver in both types of enclosures, though reactionaries would argue with that too.
for a minute, i was starting to get interested in the LM1875 design as 25wpc is more than enough power for my needs, and at least as it applies to tubes, i've gotten the impression that lower powered simpler amps are higher fidelity along the same lines that chip amps are closer to being straightwire, but i've seen some calling 1875s a little harsh. that's why i was so keen on comparisons. most of what i've read seems to lean towards the LM3875 is "the design" that's best overall. if you can shed some light on why i might like the 1875 (i like the idea of just 1 per channel) might be better or the MyRef, which is ANOTHER new to me design, i'd appreciate it.
instead of zeroing in on an amp, i just keep getting more confused as new ones pop into the search.
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Of course, LM1875 will sound harsh if it has replaced a far different amplifier like these two cases:
If replacing a Class A amplifier, make a paralleled LM1875 amp for that same rich dark voice.
If replacing a Current Drive amplifier, add the variable current drive circuit to LM1875 for leveling the response of your full range speaker driver.
The following scenario is likely (in my opinion):
Given a full range driver and a current drive tube amplifier, somebody tried a chip amp and discovered their frequency response went like "/" that. . . but they'd have that same problem with any attempt to run a class full range from a voltage drive amp, no matter what chip.
Conversely (or maybe likewise), if you try a current drive tube amplifier with modern speakers then you might think "wet blanket"
LM1875 is a simple op amp that obeys orders faithfully. There is no harsh effect, no laid back effect, no effects of any sort built into the chip.
It does whatever you set it for via support circuit design. PCB and layout can also make changes to audio.
By reviews, the majority of 1st time beginner projects have turned out slightly laid back and high resolution, practically perfect at the first attempt. Some of the Quasar Kits QK50 ("K50") builds come out clinical because 180k value is insufficient current for feedback resistor. For reference the gain range in non-inverting mode is from 10x to 40x and feedback resistors from 10k to 115k can be used. . . so missing the mark is hard to do! Too small caps at the amp board may be harsh and too large may be overly laid back, but Tom gave me a reference point of 330uF (the average good value for LM1875 amp board power caps) and that works fine. I used 470uF low ESR caps on my own amp for a laid back effect.
Just know that any effect with LM1875 external--not inside the chip.
Its tiny--effects just don't fit in there.
P.S.
Currently, I don't feel like promoting LM3875, LM3876, LM3886, LM4780 National Semiconductor "Overture" series of chip based television amplifiers. Those do have an effect built in, the Spike system limiter. Only tiny output devices fit inside chips. Spike is for protecting tiny output devices despite 50 watts use. But fast attack hard clipper for limiter (Spike) is an audio compromise that I really hate! There's also a wide variety of dodges to reduce Spike system distortion, and I could comment on that except. . .
Why dodge when you could upgrade?:
National Semiconductor also makes higher quality products called a Driver Chip, which is nice because you add your own high end big output devices to it, thus solving the problem entirely. You get the same high quality predrive section from the Overture series, but without the distortion of inbuilt miniature output section protected by a hard clipping screeching limiter. The Driver Chip solves that problem by simply omitting the problem. Soldering a Driver Chip solution and adding high end output devices isn't more difficult than an LM4780 project and doesn't cost much more, but the quality difference is something you might like to research before purchase.
again, you're getting technical talking about circuit whatchamawhoozit. show me "the ultimate schematic" where everything is optimal, and that's the design i'll go with. start talking about the circuits themselves, and it turns into muted trumpet notes to me. i don't do circuits. you're talking to everyone else there. show me a minimal designed amp diagram, and i can work it out, get into the technical bits, and you lose me.
what's so strange about having to argue FACTS with those that only listen to their primitive instinct (emotion) based lower brain? i do it almost every day on so many levels. people who totally refuse to accept facts REALLY get bent out of shape when you attempt to show them how they're wrong. ported speakers are distortion boxes. the air resonances they CHEAT sound with to add bass weight have no basis in REALITY. how is pointing that out strange? i'm guessing you love ports and find acoustic suspension sound "wimpy" like so many and are in a cognitive dissonance with the reasons WHY.
trust me, i've argued the point a dozen times with people, to me, that are absolute morons, who refuse to accept any facts that make their preferences look inferior. no matter what ANYONE says, ported speakers ADD DISTORTION that isn't present in the original signal. liking that euphonic sound is another issue, but you're basically listening to the sound of air resonating in a box and NOT the original signal which acoustic suspension dampens by being an "infinite baffle" that cancels as much back wave as possible.
i might not understand circuit design, but i can easily visualize what sounds do in spaces and made the "blown bottle" analogy (100% accurate) before seeing someone more technical using the exact same one. to me, it's blatantly obvious once i learned the basics of different speaker designs.
it's a truth that to many is too painful to admit. i just don't get such thinking myself as my mind works in "things are just the way they are" mode. ported speakers sound bloated and crappy because they blur the bass with resonance and acoustic suspension sounds tighter because the back wave is mostly cancelled with an air spring bonus that makes the woofer snap faster. my ears hear it clearly. that's why i like he sound of 4 1/2" woofers more than 12". less bass, but way more speed.
if you don't believe me, read up on it and you'll find 100 different sources that agree, eg. the sound on sound review of barefoot studio monitors i believe, or virtually ANY acoustic suspension vs ported pros and cons source. ports have nothing but cons EXCEPT deeper bass, but even there, it's an artifice. i've had the same argument a dozen times with people that just refuse to accept facts.
i have NO PROBLEM accepting the FACT that acoustic suspension speakers have less bass weight. that's their ONLY drawback. i'd rather hear sounds as close to the original as possible. honestly, i think maggies have "the best" bass... rolled off, but lightning fast with no box resonances at all, even tighter than 4 1/2" minis. i'm very much into percussion too, so sloppy bass drums grate on my nerves. GOOD ported speakers can sound OK, but bad ones sound hideous while all acoustic suspension sounds as good as the driver is capable of.
it's better to take away from the sound than add something that doesn't belong. boomy bass annoys me greatly. besides the speed, i guess i actually like a rolled off lower octave too. in that case, i like a deviation in EQ from the actual sound. i'm OK with that and am more honest with myself about it than port fans who treat their favorite sound like a football home team and must attack anyone that disparages it.
i'm not making it up when i say i've been outnumbered by a dozen vocal morons. when you refuse to accept facts, even when they're presented to you a dozen ways, you are a moron.
when it comes to circuit design, i plead TOTAL ignorance because i'm all about keeping it real, warts and all. to me, refusing to do the same is weird.
hey, i never underestimate the power of denial, or my ability to rub people the wrong way with this giant boulder on my shoulder, and i ain't talking about amps. admitting shortcomings isn't an issue with me.
what is and isn't better sounding in audio IS subjective, but resonance IS a form of distortion. it can't be argued, but many like to. that's my point. no one's arguing here though. i'm at a loss for words all of a sudden. that rarely happens.
what is and isn't better sounding in audio IS subjective, but resonance IS a form of distortion. it can't be argued, but many like to. that's my point. no one's arguing here though. i'm at a loss for words all of a sudden. that rarely happens.
High performance, minimal complication, LM1875.
No need to waste power on booming. The quickest and easiest fix for this is progressive current drive, installed by simply putting a capacitor in series to a woofer. Approximately 4400u (parallel pair of 2200u caps makes a low loss 4400u cap) for an 8" 8 ohm woofer. You can use less capacitance for smaller woofers.
You can also patch up port tuning very quickly by jamming the port tube full of drinking straws. You can lower the port pitch by blocking some of the straws, and that might be necessary. Finding out is quite easy.
For more information, See Bob Cordell's published papers on port tuning.
And you can block the speaker cabinet from drumming by installing some internal braces.
The two main causes of boomy bass in audio amplifiers are: Insufficient transformer amperage and undersize NFB cap. For clean bass sound, it is possible to oversize the transformer (amperage), oversize the NFB cap and undersize the input cap.
Very surprised so few have suggested LM3886 designs on this thread. I'll just link to a couple post and let readers make their own judgements.
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you saved this for a "p.s." but it looks like you meant it to be the most important thing. And I suspect it might be.
Apparently, if I wanted to play louder, without accepting the wonky influence of various limiters, I'd be needing a Driver Chip. . . with the upgrade to nice big outputs that are actually able to utilize the current of a bigger transformer.
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The National Semiconductor Overture series contains the Spike limiter which has a hard clipping effect that some people don't like. SO, if you'd like to upgrade a NatSemi Overture to better sounding soft limiting then look up Bob Cordell's Klever Klipper as seen in his Super Gain Clone project. That upgrade can result in a more neutral tone.
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It is popular to use LDR and audiophile market carbon resistors. But, the sound of those can be replicated by pairs of ordinary carbon film resistors.
Here's some examples.
Feedback resistor: Parallel pair of carbon film of same value (like 120k||120k = 60k)
Feedback-Shunt resistor: For example adding a 3.3R in series to your 2.7k.
Looks funny, sure.
However, there was no need to purchase audiophile market components at much expense, if when really ordinary components can be arranged to do the same effect.
This is especially apparent when there's gain, such as every capacitor on an amplifier board, is important. There's a variety of tweaks available and here's 2 of mine.
Collect 5 different models for each value cap, try them all and leave the best installed.
Next step can be HF bypass cap added to these, and I prefer small size electro (1u and Smaller Nichicon, usually smaller) and economy polyester dip cap (not larger than 33n, usually smaller), since these are all especially easy to use for non-abrupt (transparent) bypass caps, and I usually test drive a variety (no arbitrary bypassing), since the art of cap bypassing. . . shares some similarities with woofer to tweeter integration.
P.S.
The topic of cap bypassing comes very, very close to the topic of HF management. I believe that RF filters are important and adjustment is better than omission. We wouldn't want to consume the limited resources of chip amplifiers for amplifying non-audio signals. Instead, nicely done filters also happen to make the chip amp run cooler and less likely to sound off a limiter. Filters remove unnecessary workload. My really weird rule of thumb for causing cool running via filters is: a shunt for every pass. In doing so, it is a bypass to send non-audio signals away from the amp. Filters are good. See the datasheet for examples. Instead of omission, try better component values.
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I just started to build amps to answer the question. I'm using opamp to drive tone control at the input of the chip amp.
Just built and listened an LM1875 chip amp a few minutes ago. Like common chip amps, the bass cannot compete with discrete (but the rest outperform those in many Lin topology amplifiers).
Will find the best opamp arrangement for the pre stage first before changing the output chips.
Just built and listened an LM1875 chip amp a few minutes ago. Like common chip amps, the bass cannot compete with discrete (but the rest outperform those in many Lin topology amplifiers).
Will find the best opamp arrangement for the pre stage first before changing the output chips.
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