Dennis Had Inspire Amps

[Musica Amantem]

Bombadil wrote: "It "might" be true that your lack of "oomph" can fixed via a subwoofer. But it is my experience that when it comes to classical music, a lot of wattage is needed through the midrange."

I was on the same page until I read about the SUB configuration possibilities, which should definitely alleviate the "oomph" limitation. Evidently, this is not a black and white argument and a combination of variables are in place here, as you point out.

[Musica Amantem]

Rosco65 wrote: "... it is almost impossible to avoid instantaneous clipping during replay of musically-demanding pieces."

With 20 dB headroom needs in those demanding passages and my limited Triode-configured Inspire (which sounds magnificent when those demands are tamed), better bass management and power may alleviate the resulting "oomph" limitations, in part due to the benign clipping nature of the Triode-strapped tube amp (and all tube amps in general). Although this avenue may not suffice, it will certainly improve the much important bass management, an added benefit affecting even the already quite good acoustic jazz experience.

[Musica Amantem]

pstrisik wrote: "I understand from living "up here" in Alaska. Shipping is painful. I imagine even worse for you. Is "down there" Brazil? That memory is from some time ago when we might have had a similar discussion about other equipment, unless that was someone else."

I lived in Sao Paulo for a few years and that is where I acquired the Velodyne SUB, 10 years ago. I'm currently stationed in Panama City, Central America.

Would stuffing the SUB port on my Velodyne pose any risk to it? I'll try that first and learn from the experience. But, I'm convinced an improved SUB platform is a must in my case. Thanks for the valuable inputs.

[pstrisik]

Originally Posted by Musica Amantem

pstrisik wrote: "I understand from living "up here" in Alaska. Shipping is painful. I imagine even worse for you. Is "down there" Brazil? That memory is from some time ago when we might have had a similar discussion about other equipment, unless that was someone else."

I lived in Sao Paulo for a few years and that is where I acquired the Velodyne SUB, 10 years ago. I'm currently stationed in Panama City, Central America.

Would stuffing the SUB port on my Velodyne pose any risk to it? I'll try that first and learn from the experience. But, I'm convinced an improved SUB platform is a must in my case. Thanks for the valuable inputs.

I wouldn't think it would cause harm unless you were pushing it to audible distortion. Good question for Velodyne or on a forum if there is one.

A platform would likely help. I use a Herbie's product for the sub feet. I'd like to try platforms, but not motivated enough to do it.

[Musica Amantem]

Originally Posted by pstrisik

I wouldn't think it would cause harm unless you were pushing it to audible distortion. Good question for Velodyne or on a forum if there is one.

A platform would likely help. I use a Herbie's product for the sub feet. I'd like to try platforms, but not motivated enough to do it.

I used the term "platform" to mean a bass sub-system or configuration beyond the usual single SUB arrangement. I was not referring to the actual SUBs' physical foundations. Given the Inspire amp's unique SQ but limited by its power (especially in Triode), I'm convinced more sophisticated and thorough bass management is optimal. My wrong choice of words, sorry.

[pstrisik]

Originally Posted by Musica Amantem

I used the term "platform" to mean a bass sub-system or configuration beyond the usual single SUB arrangement. I was not referring to the actual SUBs' physical foundations. Given the Inspire amp's unique SQ but limited by its power (especially in Triode), I'm convinced more sophisticated and thorough bass management is optimal. My wrong choice of words, sorry.

An emily litella moment but there's an audiophile nerd joke in there somewhere!

[Bombadil]

Originally Posted by FloridaBoy

There is a sweet spot with these amps. Mine has the 20 watt transformers but is triode wired. *I* prefer 6L6GA's, Pope 6V6's and the GL KT77's. I wonder if it could be modded to switch between SE and triode?

Just noticed this post. We sure are running our Inspires in different configurations. Running 6V6 in single ended triode mode will probably produce about 4 watts per channel, maybe 4.5 wpc.

I know people who love that setup.

No need for a switch as you are running in both single-ended and triode. Switches are typically employed to switch between triode and ultralinear, which usually doubles the power output. My Inspire is single-ended pentode.

I do have a triode tube amp, but it is push-pull, producing about 18-20 wpc with two EL34/6CA7/KT77 tubes per channel.

[Musica Amantem]

Originally Posted by Bombadil

Just noticed this post. We sure are running our Inspires in different configurations. Running 6V6 in single ended triode mode will probably produce about 4 watts per channel, maybe 4.5 wpc.

I know people who love that setup.

No need for a switch as you are running in both single-ended and triode. Switches are typically employed to switch between triode and ultralinear, which usually doubles the power output. My Inspire is single-ended pentode.

I do have a triode tube amp, but it is push-pull, producing about 18-20 wpc with two EL34/6CA7/KT77 tubes per channel.

In my Triode-strapped amp (same as FloridaBoy's), I can't appreciate the 6V6's, which sound anemic (must be the speakers). Instead, the KT-77 / KT-88's are best all around, with the 6P3S-E and 6550's in a second tier, maybe along the 350B also. No 6V6s for me though.

[Rosco65]

Originally Posted by Bombadil

Just noticed this post. We sure are running our Inspires in different configurations. Running 6V6 in single ended triode mode will probably produce about 4 watts per channel, maybe 4.5 wpc.

I know people who love that setup.

No need for a switch as you are running in both single-ended and triode. Switches are typically employed to switch between triode and ultralinear, which usually doubles the power output. My Inspire is single-ended pentode.

I do have a triode tube amp, but it is push-pull, producing about 18-20 wpc with two EL34/6CA7/KT77 tubes per channel.

My KT88 (non-triode) puts out about 5wpc using a 6V6. Wired for triode I wouldn't expect more than 2-3wpc. I would expect maybe 6-8wpc from a triode wired KT77.

There are some inherent compromises when choosing low-powered single ended amps. We must choose very high efficiency (>98dB) speakers with their demands on space and presentation, or we must accept the ultimate limitations in output for speakers of moderately high (90-96dB) efficiency. One workaround is to compromise: choose a speaker we like but has 90-96dB efficiency and/or choose an amp with greater output. I have found my PSE to be a near-ideal compromise at ~20wpc. I get 13 dB of gain which allows me to listen at 85dB (relative nearfield) and have 20dB of headroom with speakers of 92dB.

One challenge is to get the bass power we like with low powered tube amps. Most high-efficiency drivers are ill-suited for deep bass reproduction. And those that are well-suited (like big JBL drivers) still like a bit more power than their stated efficiency would suggest. My personal approach has been to focus on getting everything above 50hz right using my tube gear and turning to the brute-force method of active bass support.

[Musica Amantem]

Originally Posted by Rosco65

My KT88 (non-triode) puts out about 5wpc using a 6V6. Wired for triode I wouldn't expect more than 2-3wpc. I would expect maybe 6-8wpc from a triode wired KT77.

There are some inherent compromises when choosing low-powered single ended amps. We must choose very high efficiency (>98dB) speakers with their demands on space and presentation, or we must accept the ultimate limitations in output for speakers of moderately high (90-96dB) efficiency. One workaround is to compromise: choose a speaker we like but has 90-96dB efficiency and/or choose an amp with greater output. I have found my PSE to be a near-ideal compromise at ~20wpc. I get 13 dB of gain which allows me to listen at 85dB (relative nearfield) and have 20dB of headroom with speakers of 92dB.

One challenge is to get the bass power we like with low powered tube amps. Most high-efficiency drivers are ill-suited for deep bass reproduction. And those that are well-suited (like big JBL drivers) still like a bit more power than their stated efficiency would suggest. My personal approach has been to focus on getting everything above 50hz right using my tube gear and turning to the brute-force method of active bass support.

I absolutely agree with your points. Furthermore, I don't think I'm missing anything if I can enjoy the larger and nicer sounding (at least in my rig) KT-77 and KT-88's (as well as others), with the nice presentation of my speakers. The 6V6 is a tube I really don't appreciate much, even in my other integrated tube amp which is purposefully designed for that tube.

The bass sub-system is a must in these low-powered but otherwise excellent Inspire units, and this is the avenue I'll be adopting after being made aware of by Peter and yourself. Having a Triode configuration makes things even more delightful for that magical mid-range, at the cost of requiring more oomph through a really balanced active SUB sub-system. In any event, once I have this SUB platform installed and dialed-in then I'll consider further power considerations, if required, which I frankly doubt.