Considering Large Tube PushPulls... Advice!

To summarize, you are getting rid of the small KEF speakers and moving toward a larger speaker that will be in the 90dB efficiency range and want some tube mid and upper range magic while maintaining some real bass slame, quickness along with good bass definition.

A Rogue amp and tube pre should get you there or certainly close. As you know rolling the tubes in both the amp and pre will fine tune that magic so what I would suggest to bring out the best bass would be two quality subwoofers like REL or the higher end closed box SVS subs. I'm sure there are many other subs to consider but the combo of tube pre/amp along with a quality sub would be a great consideration in terms of satisfying your ultimate goal.

 

One inch thick MDF cabinets and Scanspeak Illuminator drivers 7 inch mid woofer & Beryllium tweeters they have speed and dynamics like horns . The voicing is a balancing act as if you can get it bright with the wrong tubes .Having great bass control in the room is my key

 

ahh blood incantation. Right up my alley there. Not a name you’d see much on forums as these.

 

yes that’s about right. I’m going to likely go with tektons which, with their large drivers, should be enough bass for me. In fact the KEFs really had ‘enough bass for me overall. They also however had decent impact (for their size and expectation realistically). That impact is what I need to maintain. I would think having a hefty tube monos with quality trannies should deliver what I need and be able to handle the woofers on the tekton style speakers, if equipped at 8ohm etc of course. I have no problem with going SS , if that is the proper and more ideal route of course. Really hard to say without having the ability to try this all out....

 

Lipinski uses 1" MDF. Mine are 3/4", but dead as doornails. My room is crazy, asymmetrical and has the same bass issues no matter what speakers are in there. Gotta move my listening position out from the back wall.

Search Results for Query: Blood Incantation | Steve Hoffman Music Forums

 

well, I take that back haha. Saw blood inc twice last year here in philly

 

The first comment that I would make is that the choice of an amplifier would first be dependent on what speakers you are using.

Secondary would be the type of music that you enjoy.

I use both glass and sand amps, depending on the speakers that I am using.

I believe that most speakers that are sold today are designed to sound their best with sand amps.

Using a tube amp with these type of speakers is a waste of money.

If you would like to better see what I am referencing in this post, I put together a tour of my former audio room, directly following my equipment profile. The tour is complete with photos and descriptions.

I ran my Zu Audio, Omen Definitions with both a sand amp and a KT88 based PrimaLuna Prologue Five glass amp.

I switched to the glass amp on the Zu's because I just couldn't take the edge that the sand amp was giving them. I also like glass amps with vintage speakers, like the Wharfedale's.

Like @BillWojo, I also have Altec Lansing A7 theater speakers.

I am not new to A7's, having had my first pair built when I was sixteen. I had basically decided that if I wanted dynamic speakers that could produce the real dynamics of a rock concert, then I would need concert type speakers.

I went this way and never looked back.

I have three pairs of A7's. My main pair have custom ALK Engineering 500-cycle crossovers. They have been modified from a 2-way speaker, into a 4-way design, with the addition of a JBL super-tweeter and a pro-sound 15" passive, horn loaded sub woofer.

The A7's are run strictly with glass amps. That wasn't always the case. All of my audio life, I ran A7's with sand amps. It was more of a whim and curiosity that I decided to try tube amplification with them, back in 2013. I have never looked back.

But as much as I love tube amplification with the Altec's, on all of my other modern tower speakers, I use sand amps.

I like to run multiple speakers at the same time, running of the same source.

My front mains are Polk LSiM707's and are Powered with a generation one Emotiva 250-Watt XPA-2, stereo power amplifier.

They sound excellent with the Emotiva. But I would not use a tube amp on the LSiM707's.

I had been using a pair of Boston Acoustic, M-350 towers for the rear and power them with a small 50-Watt Emotiva power amp.

I understand what you mean by SET amps not having enough power to deliver the necessary dynamics from some music. But with the A7's being about 100 dB. in sensitivity, the 22-Watts that the LM518iA that I had, would really do justice with them.

But, even with high sensitivity horn loaded speakers, I still relied on a commercial subwoofer and that was powered by a Crown class "D" power amplifier, an XTi-2000. I have the XTi-2000 running in bridged mono mode, which can deliver 1,600-Watts to the sub. The sub can maintain a continuous SPL of 133-dB.

So I can do dynamics with an SET, but it does take a very special pair of highly modified speakers to do so.

As Billwojo also commented, large tube amplifiers are expensive to operate.

But, if you do want to have the power and dynamics of a sand amp, that is what a high powered tube amplifier can deliver.

Most people might opt for KT120's, for the power and frequency extension but I prefer the more vintage tube sound of KT88's.

But, again, having speakers with very high sensitivity and being naturally very dynamic, the KT88's work for me in the Rogue M-150.

Again, the choice of a tube amplifier is highly dependent on your choice of speakers. In most cases, I don't recommend glass amps with most modern speakers. Sand amps will be as good, if not better suited.

 

Speakers will be tekton double impact or lore. I haven’t decided which I’m grabbing yet. The double impact will obviously deliver in visceral impact and cover full range very well, while the lores being a smaller foot print yet still equipped with a 10” driver. We’re at 98db with either, with customization as to 8 or 4ohm. So way, so yes, these are drivable by SS or tube no doubt.

 

One thing you've not commented on is the size of your room, but speakers with this efficiency are going to be driven quite well with a modest tube amp. 140 "tube watts" with a 94 to 98 dB speaker is going to be a bit odd.

Put another way, once the room is pressurized, you probably don't want it much louder. You want a usable range on you attenuator. I feel like I've got a pretty nice match when I have useful volume from 8:30 to 11:00 on the dial. With the difference in loudness and mastering, I like having that micro control so I can get the volume level just right.

If you only have a very small area where the volume is acceptable, it becomes very had to adjust, particularly with a remote.

If you are at 100 dB at 8:00 on the dial, it's going to be complicated.

 

Yes had these similar concerns. My designated room is a 13.5 x 15.5 spare bedroom with 8” ceilings. Hence why I may go with the lores. The double impacts are big. Will they pressurize the room to easily etc? Will I not take advantage of the total sound of the impacts from say 8-9 foot away? Perhaps. I have been of the idea that too large of a speaker in a room smaller than ideal for such, can end up overloading the room so to speak. Eric Of tekton states that this is mythical and he has never found a speaker to be ‘too large’ for a room, in a video covering his speakers. I’m very aware of a 98db speaker being able to function off of as little as 2watts etc. It has been said that even though these tektons are of high sensitivity, extra power does seems to robust the sound, and help control the woofers/drivers for dynamics and fast transients. Would a pair of vtl450’s or rogue m-180’s be overkill? Absolutely. Meanwhile they are equipped with very large iron, which is really required for quick response to dynamics and control of the lower frequencies in tube amps, ie. being my best bet at delivering slam and oomph that I desire. If I went with a lower powered tube amp or integrated like say a Cronus magnum or even a vtl st-150 or st-85, I’m not sure if smaller power supplies would infringe on that power and control id ‘like’ to find in a tube amp/s....Even with such high sensitivity in the tektons..
Or of course, I go with a SS power amp.

I will say, I haven’t given thought to the possible attenuation oddities as you’ve mentioned. Make a good point.

 

I like big speakers, even in small rooms but that's just me.

I question that the Lore's will give you the SPL and the dynamics that the DI will?

I would like to hear the DI myself.

 

So if I'm streaming Starspawn the digital mastering is kinda punchy and my room is full of sound at around 9:00 on the dial. The vinyl is another story. It is mastered differently and is thick and dense and I might turn it up past 11:00. Very small increments in the volume knob really change the way the speaker sounds, and those drivers are trying to keep lots of little sounds that overlap in frequency all sorted out. It's a Goldilocks sort of thing, I'm sure you know. The driver is going to be the point where the sound turns mushy. That's where acoustic suspension designs really shine. The driver is designed with the right magnet to function in a sealed box with a certain volume and that constant pressure in the box is really helping the amp control the driver so that the recovery is very fast. That and a cone material that is super light and rigid means the driver can keep all those overlapping sounds sorted at a higher volume. Having the ability to move the knob a little (TWSS) and perfect the way the amp digs into the drivers can't be underestimated. I've had a loud source before and had to fiddle with inline attenuators and that sort of thing.

Whatever you do, coordinate so you can have a trail period. You might be able to get away with a passive preamp is it was all well chosen.

 

while I’m more concerned in dynamics, yes the DI’s are going to throw bigger sound and punch harder undoubtedly. The lores are spoken Of highly as well however

 

Just be aware that several review measurements have shown tektons efficiency is significantly lower than specified.

 

It is easy to overload small room with a large speaker . I heard the Tekton Moab s at CAF 2019 and felt the room was overpowered . If you are looking for the ultimate set up Google Dr Earl Geddes on distributed bass . Food for thought multiple subs are active room correction

 

Yu

Yup, am aware of this. Some models are a little more off than others apparently but none the less they’re ‘close’ to spec. Obviously will not be an issue as whether I go with a SS or tube amp, I’m going with far more wattage than I’d need.

 

I always thought the same‍♂️. Thank you, u will look this up now. Also, thanks for the sub recommendation. I am trying to attain adequate bass without subs at this time. With 10” woofers driven by appropriate amplification it should be enough for me.

 

LAMM 1.2

 

Update.. Have been reading up regarding impedance/damping factor etc. Before I continue, yes, I realize damping factor is a measurement on paper that sometimes does not tell the whole picture and that experimenting is really the best way to know how an amplifier will mate with a particular load (aka speakers).

I will be perusing either vtl 450mb monos if I go tunes, OR a McCormack DNA225 if I go SS. What I’m concluding is that, if proper mating is done, 450’s have the power for fast transient and slam, with huge custom wound transformers, at 90lb per mono. The interesting thing about vtl is their amps are designed to run most linear at 5.5ohms. This is the situation with all of Manley’s designs. This, the vtl’s actually are designed to hang out a little lower in the impedance range than most tube amps. Now.. With the plan to order tekton speakers I will need to decide on 8ohm or 4ohm. I was of course considering 8 would be more ideal if I go with the vtl’s, but really, it appears a 4ohm load may actually be more ideal for these. A Stereophile review with 450’s did measurements showing that while in Tetrode mode they were more linear at 4ohms and while on triode, more linear at 8. I would love to hear any input regarding this! This is a bit more into the technical side of things, so is more particular to those with the knowledge of course.

I realize I can drive the tektons with less wattage.. However. Wattage doesn’t tell the whole picture regarding me wanting to have good dynamics that keep up with quick transients and such. Power supply is essentially just as important, or more important. Otherwise, I’d be okay grabbing a rogue Cronus magnum to meet my needs, but I know the vtl’s will be a far safer bet, and a bit overkill perhaps, for having the power reserve to meet the desires I’m asking. I’d love to be able to just grab a CM honestly, but am leery that i may feel a bit short if I did so. I’m not retired, listening to music hours a day. I get a few hours a week between work, and a new baby, so I’m not much worried about running all of the tubes in these amp when I likely don’t need this many. If I were listening 4 hours a day, maybe a different story, sure.

Meanwhile I know the McCormack is a beast of a transistor amp as well and would operate fine in either, but i would order speakers in 4ohm for the McCormack.

 

You are right about overkill on the amp side. I think many people have hinted at this in responses. What you want to look at is the impedance curve of the speakers in question. A tube-friendly speaker is going to have a pretty steady impedance curve, and by steady I mean not a bunch of ups and down but also not a lot of steepness in the curve. Wherever that curve dips down low is where the tube amp will struggle the most to control the drivers.

Still, there's no substitute for real-world experience. I have a few friends who have Lores and they do very well with basic SS amps like the Rega Brio. I have no doubt that the Rogue you mention would handle the Tekton with easy confidence. Once you push those vented drivers to the point they lose composure, no damping factor or wattage or output transformer is going to make any difference.

Again, I have less than 50 tube watts driving a 4 ohm speaker (which probably dips down to 3.2 or so) with a steady impedance curve and it has no issues.

The difference with tube and SS is that tube amps have a soft distortion at higher output, where SS amps, although much lower distortion overall than tube, have their best, lowest distortion performance at higher volumes. Tubes really, really shine at lower volume levels. They tend to flesh out the sound very well without going loud. They also, depending on the level of negative feedback, add harmonic distortion, which our brains interpret as being spatial queues—so our perception of the space between elements of the recording is heightened and it sounds real.

You don't see many people pair super efficient speakers with super powerful tube amps, and there's a reason that they don't. I honestly think you should try a few amps with the speakers you choose and return what doesn't work for you.

 

One question I would ask is how they change a speaker from a 4 ohm to 8 ohm load. The impedance is a function of the drivers and crossover and it is not something that can be easily changed. I know Zobel networks are popular and maybe they are adding something like that internally.

 

This all occurs within the design of the crossovers.

Also, regarding power speakers, or having an abundance of power more than required.. If I went with more practical matches output tube amp I would probably go right to an integrated Cronus magnum.

 

I'd be inclined to take the crossover as designed. These minimal component crossovers sound good for a reason.

Can you get a Cronus Magnum in for an audition with the speakers? I know when I bought my speakers I did so only because they had a liberal return policy, essentially allowing you to audition the gear with a window to return. Again, KT120s are a really pleasant current production power tube that is super reliable and sound very good. They make the difference for me, and that's in part because they give the amp a bit of headroom.

 

I think that spending a lot of money on VTL monoblocks is a bit excessive to drive a speaker such as the Lore or any other Teckton speaker.

A CM III will more than be sufficient.

I will also comment that I completely ignore things like "damping factor, impedance curves" and the like.

 

Hmmm... By throwing a 4 ohm resistor in series with the entire speaker perhaps? That would indeed be a scary thought, if it were to be true.

So your concerns about this are not misplaced IMO.