GR Research Brute Speakers

Presb4 · « **Reply #40 on:** 23 Oct 2023, 10:47 pm »

Ok, so onto mounting the crossovers.

I laid out the crossovers so the circuits flowed from side to side electrically. I did not have a real reason for doing it this way other than its how my brain works but it had an advantage in the end. I found that this made the final wiring much cleaner in the cabinet. As you can see I, rotated the crossover board and placed it in the bottom on top of the norez sheet. I simply screwed it down through the norez and onto the OSB below, sandwiching the norez. This worked well and assured I would have no crossover board vibration buzz in the future.

Also with the crossover sideways, it aligned the crossover outlets wires to run straight up the side wall toward the mid and tweeter pocket. I then covered the wires with the fiberglass batting. This kept the wiring routing clean and acted as a cushion to keep the wires from vibrating against anything.

Presb4 · « **Reply #41 on:** 23 Oct 2023, 10:55 pm »

One 3" thick batting of fiberglass in the top Mid/Tweeter section was added followed by another 3" thick 22" wide sheet of fiberglass insulation in the bottom woofer section.

Presb4 · « **Reply #42 on:** 23 Oct 2023, 11:02 pm »

The speakers were then laid out and soldered in. Two things of note.
1) the woofer is wired in as reverse polarity on purpose.
2) the tweeter did not have a polarity marking on the speaker. A quick google found that the small tab is normally the negative side, so that's what I went with???

Presb4 · « **Reply #43 on:** 23 Oct 2023, 11:06 pm »

Some quick work with a torx bit and the speakers were done.
Now I just have to get them into the house from my work shed.... Man I bet these brutes are around 60# each..

Presb4 · « **Reply #44 on:** 23 Oct 2023, 11:18 pm »

So at this point I see this build post has been viewed over 4k times. So I figure you all are seeing something you are interested in.
I decided to built the brutes for a few reasons and I would like to know what your reasons for buying, thinking about, or lurking might be

For me I was looking for:
1) A high quality speaker design that I could afford.
2) A speaker that had good sensitivity to use with my Dynaco ST-70 tube amp.
3) A speaker design with higher and even impedance that my tube amp would like driving.
4) A fun project that was not over my head and one that would result in value I could keep for many years to come.

Hows about you?

jmimac351 · « **Reply #45 on:** 23 Oct 2023, 11:35 pm »

Why?

Today, while I was swapping out one set of monitor speakers for another... because... she asked me "So, are you collecting speakers now or something?"

Me: "Oh no, I've owned this pair for 10 years, at least."

That is one big benefit of playing with smaller speakers paired with subs.

Nice job on the Brutes. I am sure they sound excellent. That Duratex finish is a great option.

Early B. · « **Reply #46 on:** 24 Oct 2023, 12:50 am »

Quote from: Presb4 on 23 Oct 2023, 11:18 pm

I decided to built the brutes for a few reasons and I would like to know what your reasons for buying, thinking about, or lurking might be

We lurk because audiophiles love build threads.

Tyson · « **Reply #47 on:** 24 Oct 2023, 01:48 am »

How did you get them into your house? Hand truck?

Presb4 · « **Reply #48 on:** 24 Oct 2023, 02:36 am »

I moved them one step at a time. They are now in and running.
Im still running through my most loved songs before I have an opinion tell.
Its a good night

Tyson · « **Reply #49 on:** 24 Oct 2023, 02:45 am »

Quote from: Presb4 on 23 Oct 2023, 11:06 pm

Some quick work with a torx bit and the speakers were done.
Now I just have to get them into the house from my work shed.... Man I bet these brutes are around 60# each..

For a speaker called "The Brute", they sure do look refined. Finesse, as well as power. Nice job!

Presb4 · « **Reply #50 on:** 24 Oct 2023, 04:07 am »

Quote from: Tyson on 24 Oct 2023, 02:45 am

For a speaker called "The Brute", they sure do look refined. Finesse, as well as power. Nice job!

Thanks Tyson.
I have had a few friends over to the house tonight to demo and everyone has said, Whoa when they first see them.
Now I just have to figure out how to get them to leave...

Their wife's keep calling wondering where they are and its reminding me of this old meme.

Tyson · « **Reply #51 on:** 24 Oct 2023, 04:16 am »

Quote from: Presb4 on 24 Oct 2023, 04:07 am

Thanks Tyson.
I have had a few over to the house tonight to demo and everyone has said, Whoa when they first see them.
Now I just have to figure out how to get them to leave...

How do they sound with that ST70 of yours?

Presb4 · « **Reply #52 on:** 24 Oct 2023, 04:46 am »

So far the Brutes are a great match with my ST-70. I have only been using the EL34's in the ST-70 tonight, but need to give the KT-77's a roll as they should be able to push the lower and upper limits of the brutes better. The EL34's have a great mid range for acoustic and jazz played trough the Brutes. But I am starting to dig into 90 alt rock and the KT 77's should be the ticket for tomorrow. Currently giving the "The The - Soul Mining" and "Pixies - Surfer Rosa" a whirl and loving it. Then maybe later this week I will hook up my 100 Watt SS Vidar 2 to give them a real push into the upper db's.

So far the Brutes most surprising attribute is the high end not the low end. I was thinking that these speakers would be all about the bass. They defiantly look like bass speakers. But the bass is very natural, balanced and quick, not boomy at all, and I have them in a med to small room. 12'x14'. Having mostly used ported speakers in this same room up near the wall, I know boomy and these are not.

The highs are very detailed and crisp. way more so than any other speaker I have owned so far. The details I am getting, the tappy tap of the drum stick on a high hat is unbelievable. The sound stage depth and height is awesome and the center stage is locked in anywhere I sit on my couch, and they are by no means broken in. Should only get better

Tyson · « **Reply #53 on:** 24 Oct 2023, 05:47 am »

Those woofers look like the same ones that were on the V2's I built a while back. If so, they'll start off a bit 'tight' and 'light' sounding and will become fuller and more punchy after about 100 hours.

mkrawcz · « **Reply #54 on:** 24 Oct 2023, 09:26 am »

It definitely took at least 100hrs for the Eminance woofers on mine to open up.

Presb4 · « **Reply #55 on:** 24 Oct 2023, 04:39 pm »

Quote from: mkrawcz on 24 Oct 2023, 09:26 am

It definitely took at least 100hrs for the Eminance woofers on mine to open up.

Good to know, I will keep them playing this week.

I rolled in some KT77's this morning and the total response from the ST-70 is wider over all. Bass filled in a bit and the highs have a bit more sparkle.
A quick in room sweep this morning, I could hear the ST70 - Brute combo making an even db response between 42Hz to 15Khz before significant roll off . The 15kHz may just be where my hearing poops out these days LOL.

In room, the crossover hand off from the tweeter to mid, around 1.6kHz, was so good I was unable to detect it. The mid to woofer crossover point around 180Hz was also very smooth, it was almost undetectable.

Presb4 · « **Reply #56 on:** 25 Oct 2023, 11:12 pm »

Just an FYI for those out there that might be looking to use a Dynaco ST-70 with the GR Brutes. This will be my last slightly off topic comment for this thread.

Seeing how the ST-70 has a 4, 8 and 16 Ohm speaker tap and the GR Brutes are around a 10 -12 Ohm load, when using the 8 Ohm speaker connections on the ST-70 this presented a bit of a OT impedance mismatch . Doing some quick math finds the P-P load resistance on the output tubes to be around 6000 when used in this combination. EL34 tubes like a lower P - P load of closer to 4400, so looking up some tube specs I found that 6L6GC like a higher P - P load than the EL34's when used in this amp and biased correctly.

Rolling in some 6L6GC and connecting the Brutes back to the 8 Ohm taps, this combo sounded all around fuller to me. The OT are running cool, and the speaker / OT / Tube impedance isnt a mismatch anymore.

I did have to set the fixed tube bias a bit higher at 50 - 52ma to get the wattage back up to 35w rating and use a SS rectifier to limit any sag at the higher current load might cause.
Mind you none of this was a must, the amp and speakers sounded great in stock form when using the EL34's but a tinker'r has to tinker and I feel this change, resulted in a change for the better.

Tyson · « **Reply #57 on:** 26 Oct 2023, 05:06 am »

6L6-GC is tied with the KT66 as my favorite tube in a push-pull amp.

Beautiful amp!

Presb4 · « **Reply #58 on:** 3 Nov 2023, 08:29 pm »

OK, but how do they sound???
Well I have around 75 to 100 hours of ARV / 2 Ch music normal use - burn in time now on the Brutes, so I figured it was time to spend a few hours doing some critical listening. Today everyone was out of the house and I had the day off from work, so this is what I did.
Buckle up, I have a good bit to say....

But if you want the TLDR version:

The good - The Brutes are the best all around, full range speaker, I have personally owned to date. They have the pedigree to recreate details with speed and grace. They image well enough to have anyone but the most hardened audiophile saying wow. They are neutral in tone, balanced across the full range and lack any coloration as best as I can tell.
As with most things in life, its all about the details and in any 2 CH system, each component is a detail you can not over look. Speakers are one of those details that connect you to everything else in the chain. Having great speakers is uber important to any system, and should be where you start, as they will define the effect each of your components have. Danny I love these speakers, thank you.

The bad - Well this is a stretch, but the brute specs are a bit misleading to a novice. They are 91db speakers but are also on average 12 ohm too. Most of the speakers I own are in the 84 to 86 db range and 4 to 6 ohms. I was thinking that wow 91 db will be so much easier to drive, but not really. In my experience the increased db sensitivity is sucked up by the increased 12 ohm resistance of the crossover. So do the brutes play louder in my system with the volume knob turned to the same level....
No its about the same in room level as my other lower sensitivity speakers. But don't fret, any average 50 to 100 watt amp can drive these to normal, not going to piss off your wife levels. But if that is what you want to do, 100 to 200 watt amps are what is needed in a moderate to larger room.

Details to follow.

Presb4 · « **Reply #59 on:** 3 Nov 2023, 09:48 pm »

Now for some details...
I wrote the TLDR for those who are just flipping through the forum looking to quick high level opinions.

Now I would like to dive into the details of where I have been and what I am hearing now coming from a guy with a modest system, that has grown over the last 15 years, with modest funds, in a small den (10' x 13') that is used by my wife and I as a TV room.

Well where have I been? I have had a number of different set ups, all of which were really just AVR systems for TV and Movies with occasional 2Ch listening to some good old rock and roll. What many of you may have had in the past and and what you would get from a big box store like Best Buy. I have owned Bose, Elacs, Pioneer, Yamaha, Polk you know common stuff.

As I got older I started to shift from a quantity to a quality buyer. This was around the time my wife started looking at me a little cross eyed every time I said I wanted to try a new stereo component. Did spending more money on better components bring in more quality? Yes and No. Yes my system sounded different, and I liked what I was hearing, but it was missing the wow factor.

A good friend of mine and I were talking a few years back and he is a life long audiophile. He made the comment to me that with the speakers I had I would never really hear the changes I was making. At the time I had a nice pair of Elac book shelf speakers with a 10" powered sub and remembered thinking, It sounds good to me, what is he talking about.

A year or 2 later I purchased a few Schiit Audio products. Now to some they may be rolling their eyes thinking Schiit is not Hifi. I am here to say, not true. Sure they have some modest gear that is just ok, but their higher end stuff is really good quality for the money, excellent value, and basically made in America. This was also my first purchase of a good DAC and tube pre-amp and dedicated power amp. Much of this I paired up with my Polk R600 tower speakers and loved the combo. Then my audiophile buddy had me over to listen to his All VTL tube amp and Splendor speaker system, then I knew what I was missing. So what does any of this have to do with the GR Brutes? I'm getting there, hold on.

Wanting that same Wow factor and knowing I did not have the funds to get the same system my buddy had, I said there has to be a way. So I asked him where to start. He said, "start with good speakers", drop the mic. I said but I dont have the funds to get speakers like you do. He then said, well you could just get one of the GR Research speaker kits and build them yourself. So I did some more research and took the leap.

The Brutes were my first real purchase into "HIFI" gear IMO, besides rebuilding a Dynaco ST70 tube amp.

So what have I learned on this adventure so far... Speakers really do matter.

Having modest quality speakers with cheep crossover parts is like having a Porsche with all the horsepower one would want and driving it on bald tires in the rain. No matter what you do to the shocks, springs, exhaust, the paint, you name it, you will never get the horse power to the ground without great tires. Speakers are no different. They are what connects your system to your environment (room).