Dennis Had Inspire Amps

[x3workshop]

Originally Posted by Comzee

I was moving my kt88 Fire-Bottle when I heard something rattling inside, so I took the back off.

It was a rubber sleeve that wrapped around a resistor near the PSU. The heat literally baked it off, it was hard and rattling in the case.
Resistor pictured: https://c1.staticflickr.com/5/4299/3...662e931d_b.jpg
It's the one that says XICON.

I also noticed while I was looking in there that similar resistors near the back melted the coating off some other resistors, pictured: https://c1.staticflickr.com/5/4297/3...82acbedb_b.jpg
I hand parted those four resistors apart as far as the wire would let me. They were originally smashed together with no space. I also drilled holes on the underneath cover. Three holes under the PSU, and four under those four resistors.
Now when I have it on, I can squeeze my hand underneath the Fire-Bottle and feel 100F+ heat billow out of the amp

I always knew the thing got hot, but I assumed Dennis knew best as far as heat effects. I mean a metal box with no vents is a torture chamber for electrical parts.
I know the holes in the bottom cover might reduce resale, and some might think it ugly, but a steel box with no vents is no bueno in my book. Just thought I'd pass the info along.

Those are solen film caps that are looking a bit fried there, not resistors.

[x3workshop]

Originally Posted by Musica Amantem

If you really want neat, seamless bass, try the 100 Hz filters

I'm glad you're such a die hard convert. Best kept, inexpensive secret to improved performance.

[nhparrot]

Originally Posted by x3workshop

I'm glad you're such a die hard convert. Best kept, inexpensive secret to improved performance.

Interested in the FMOD filters but I have a question. If my sub's highest crossover is 90Hz, would I still use a 100Hz crossover and not use the sub's internal crossover? FYIW my mains have a specified frequency response 38Hz-25kHz, ±3dB with a 5kHz crossover.

[Musica Amantem]

Originally Posted by nhparrot

Interested in the FMOD filters but I have a question. If my sub's highest crossover is 90Hz, would I still use a 100Hz crossover and not use the sub's internal crossover? FYIW my mains have a specified frequency response 38Hz-25kHz, ±3dB with a 5kHz crossover.

I'm sure x3workshop will provide a more informed reply. To me, this is just common sense. We all know floorstanding loudspeaker design is a tradeoff / compromise across such a wide frequency range. Nothing depicts the lowest 100 Hz better than a good, purposely-designed SUB.

Now, instead of reinforcing those low frequencies with the SUB, the filters allow a seamless, continuous bass line across both camps (under and above 100 Hz). The added benefit with the approach is the relief on the flea-powered amp of those nasty last 100 Hz. The end result is better bass, mid-range and highs.

To answer your specific question, you can either use a lower std high-pass filter at 50Hz or you can use the std 100 Hz filter and lose representation of frequencies: 91, ... ,100Hz. Both approaches are improvements, as those last 50 of the 100 Hz range are the most difficult. Your choice. I would personally sacrifice those 10 upper Hz and improve the rest. Maybe this supplier can accommodate a custom 90 Hz High Filter?

Originally Posted by x3workshop: "I'm glad you're such a die hard convert. Best kept, inexpensive secret to improved performance". Trying to keep learning

[x3workshop]

Originally Posted by Musica Amantem

I'm sure x3workshop will provide a more informed reply. To me, this is just common sense. We all know floorstanding loudspeaker design is a tradeoff / compromise across such a wide frequency range. Nothing depicts the lowest 100 Hz better than a good, purposely-designed SUB.

Now, instead of reinforcing those low frequencies with the SUB, the filters allow a seamless, continuous bass line across both camps (under and above 100 Hz). The added benefit with the approach is the relief on the flea-powered amp of those nasty last 100 Hz. The end result is better bass, mid-range and highs.

To answer your specific question, you can either use a lower std high-pass filter at 50Hz or you can use the std 100 Hz filter and lose representation of frequencies: 91, ... ,100Hz. Both approaches are improvements, as those last 50 of the 100 Hz range are the most difficult. Your choice. I would personally sacrifice those 10 upper Hz and improve the rest. Maybe this supplier can accommodate a custom 90 Hz High Filter?

Originally Posted by x3workshop: "I'm glad you're such a die hard convert. Best kept, inexpensive secret to improved performance". Trying to keep learning

I think a 70hz High pass filter would work just as well for your setup. Perhaps even better.

One thing I will mention about 'Harrison Labs' the manufacturer and vendor of FMods. He seems to have become rather outspoken regarding his religious and political views and has used his website as a pulpit. Be prepared.

[nhparrot]

Originally Posted by x3workshop

I think a 70hz High pass filter would work just as well for your setup. Perhaps even better.

One thing I will mention about 'Harrison Labs' the manufacturer and vendor of FMods. He seems to have become rather outspoken regarding his religious and political views and has used his website as a pulpit. Be prepared.

Thanks

So what you are saying, is use 70Hz high pass FMOD at the Inspire amp input, correct?

What crossover point on my sub would you recommend? Since I do have a decibel meter, should I play with the sub crossover points and adjust as needed for the best seamless transition?

[Musica Amantem]

Originally Posted by nhparrot

Thanks

So what you are saying, is use 70Hz high pass FMOD at the Inspire amp input, correct?

What crossover point on my sub would you recommend? Since I do have a decibel meter, should I play with the sub crossover points and adjust as needed for the best seamless transition?

I did not know there was a std 70 Hz High Pass Filter on offer. Evidently, that is the best approach. Just dial your SUB crossover at 70 Hz to get a seamless bass line. It is mathematical, because the filters make sure the amp does not work under 70 Hz. To avoid reinforced bass, just cross the SUB at 70 Hz. Yes, those filters go at the end of your amp's input cables (R + L) and connect directly to the amp, as usual.

[x3workshop]

Originally Posted by Musica Amantem

I did not know there was a std 70 Hz High Pass Filter on offer. Evidently, that is the best approach. Just dial your SUB crossover at 70 Hz to get a seamless bass line. It is mathematical, because the filters make sure the amp does not work under 70 Hz. To avoid reinforced bass, just cross the SUB at 70 Hz. Yes, those filters go at the end of your amp's input cables (R + L) and connect directly to the amp, as usual.

What MA said! Should work very well and you can tweak your sub's xover so that there is no bump.

[nhparrot]

Originally Posted by Musica Amantem

I did not know there was a std 70 Hz High Pass Filter on offer. Evidently, that is the best approach. Just dial your SUB crossover at 70 Hz to get a seamless bass line. It is mathematical, because the filters make sure the amp does not work under 70 Hz. To avoid reinforced bass, just cross the SUB at 70 Hz. Yes, those filters go at the end of your amp's input cables (R + L) and connect directly to the amp, as usual.

Originally Posted by x3workshop

What MA said! Should work very well and you can tweak your sub's xover so that there is no bump.

Thanks for the input, ordered a set of 70Hz high pass filters

[Comzee]

I'm going to throw an odd scenario at you guys, and see if anybody thinks they know what it is.

I sometimes use my fire-bottle for headphones. I rarely do though because there's a decently loud hum in the right channel (something you can't hear with speakers).

I recently moved, and I noticed something peculiar. When the furnace kicks on (same house circuit) the hum goes dead silent. That's pretty cool in my book, since the fire-bottle kicks the ass of my normal headphones amps.

Anyway, I'm not sure what the extra load on the house circuit is doing to the electrical properties coming out of the other outlets (of which my fire-bottle is connected). I'm wondering if I can replicate those properties without the furnace being on, to reduce hum to zero?