Dennis Had Inspire Amps

[trackpad]

Originally Posted by BearCityUSA

I'm taking a different tact. Eliminate the possible external sources by taking both Pre and KT to the office today. Heck, I even have a different power company there. If the hum is still present then I figure it may be a wiring incompatibility between the two.

I think I have solved my problem. I cleaned all of my tube pins with deoxit and fine steel wool. Followed by more deoxit and a paper towel wipe. I sprayed a bit into the sockets. I swapped the 56 tubes for 27s and it sounds a much better!

I also have globe 27s, they test strong but the noise is audible when playing. They are really microphonic. I wonder if anyone had used tube dampers with the globes.

[x3workshop]

Originally Posted by trackpad

I think I have solved my problem. I cleaned all of my tube pins with deoxit and fine steel wool. Followed by more deoxit and a paper towel wipe. I sprayed a bit into the sockets. I swapped the 56 tubes for 27s and it sounds a much better!

I also have globe 27s, they test strong but the noise is audible when playing. They are really microphonic. I wonder if anyone had used tube dampers with the globes.

I have been using some dampers on my globe 56's & 27's. It doesn't eliminate the microphonics, but it reduces the propagation & occurrence substantially. I hate the way it looks though.

[Musica Amantem]

Originally Posted by x3workshop

MA,

That was me that suggested the F Mods.

Been away from the forum for a bit. I've actually been caught up with listening to a Citation II that I recently rebuilt along with a pair of my rebuilt Acrosound UL II's. NOT SET! They're glorious amps though!

The F Mods solved the nagging problem of the Inspire losing steam when I was pushing it hard. Once I sent <100hz to a sub and lightened the load on the Inspire it came alive for me. I won't go back.

Now if you really want to see what else you can gain, try subbing a 6BL7 into your LP-27a.

I need to thank you for an excellent suggestion! When you explained how it works, I was convinced, at least on paper, but I really dig it now that I've been using it. It is the single most effective way of improving both seamless low frequencies and improved overall performance in the Amp. It also does not seem to bring any unwanted noises or to limit the original signal in a perceptible way.

6BL7, never heard of it. I know it could replace the 6SN7 in our amps, but not too popular since these are quite rare NOS's. I think I'll follow your suggestion this time around too

[trackpad]

Originally Posted by x3workshop

I have been using some dampers on my globe 56's & 27's. It doesn't eliminate the microphonics, but it reduces the propagation & occurrence substantially. I hate the way it looks though.

What dampers are you using? I'm interested in trying them myself.

[FloridaBoy]

The 6BL7 is like a 6BX7 with more gain. They are not expensive.

[FloridaBoy]

Originally Posted by Musica Amantem

I need to thank you for an excellent suggestion! When you explained how it works, I was convinced, at least on paper, but I really dig it now that I've been using it. It is the single most effective way of improving both seamless low frequencies and improved overall performance in the Amp. It also does not seem to bring any unwanted noises or to limit the original signal in a perceptible way.

6BL7, never heard of it. I know it could replace the 6SN7 in our amps, but not too popular since these are quite rare NOS's. I think I'll follow your suggestion this time around too

Enablers. Now you have me considering a subwoofer.

[Musica Amantem]

Originally Posted by FloridaBoy

Enablers. Now you have me considering a subwoofer.

Sorry! Seriously, the amp works more freely and bass lines improve tangibly.

[Bombadil]

With my little Inspire, an SE EL84, a subwoofer is an absolute necessity. It produces little output below 70Hz. I roll in a sub at 100Hz on it. On my 17wpc KT88 HO, I run it into full range speakers and it does a good job through the lower bass. Not great, but with fair power, definition, and presence. A bit loose & warm, really nice with some types of music. But not as much slam, definition, and really deep bass as with a good SS amp. My speakers -3dB point is around 26-28Hz, so they can reach down real low. I don't usually employ a sub in this system, but I can and have.

Running either Inspire amp into any of my smaller monitors, I own bookshelf speakers from Focal, Von Schweikert, and Spica, I find that a well-integrated subwoofer can add a nice deep bass balance.

[Wgarcia]

I run 2 REL subs from the same era…a Q150e 10", and a Q108e MKII 8"…and since they utilize the amp's output it would seem there's plenty of bass generated by the Fire Bottle. Without the subs my mains are fairly flat to around 40hz (Sonist Recital 3s) and the amp gets to that area just fine, but with the subs it's sublime (sorry).

[Musica Amantem]

Bombadil: "I find that a well-integrated subwoofer can add a nice deep bass balance."

I used to do that, but a SUB that merely reinforces the full range does not have the same effect. Replacing those lower frequencies with the SUB alone, and allowing the amp to work everything else out without that burden, makes a tangible difference. I strongly suggest you try that filtering approach.