PDA

View Full Version : Boston Acoustics GT-2125 Review



neo_styles
02-05-2013, 12:22 AM
Review of Amplifier: Boston GT-2125

So as most of you who frequent Sonic Electronix know, the Boston Acoustics GT-2125 is being sold at fire sale prices. Hell, the whole Boston lineup is if you happen to go onto their website and look into the refurbished items. So I took this opportunity to go down the whole five miles it takes to SE HQ and pick mine up today. Yes, I'm that guy who's dumb enough to save an extra 5 bucks on a refurb, but there's a method to my madness. I want you guys to have the new stock because I could care less if my amp doesn't come with the manual or all the pack-ins or if it happens to have a couple scuffs on the mounting plate. Anywho, my point is you can buy the amp new from SE for 110 or you can be like me and buy a refurb (one left at the time of this review if that 5 bucks ends up a dealmaker).

BUT WAIT, you're still probably asking, IT'S A FIVE DOLLAR DIFFERENCE! ZOMG WHY DIDN'T YOU BUY IT NEW?!!?! Because somewhere in the back of my head, I have a feeling this refurb has been touched by Boston more recently than the new stock. I could be wrong, but whatever. Let's not forget what these things went for when they were brand new.

Now for the obligatory first picture and specs!
https://lh5.googleusercontent.com/-UsBVfMl0o30/URCFoVPmuPI/AAAAAAAAGk4/By4HR9T7dZQ/s1095/IMG_0315%5B1%5D.jpg
https://lh3.googleusercontent.com/-LyUel9t19Bo/URCH98fGe6I/AAAAAAAAGlk/2nAiFlGNxpc/s698/GT2125+specs.jpg
***Note. This is a Class A/B amp. It's mentioned later in the thread, but I'll add it here***

So as you can see it's tiny, but it's a workhorse. At just over a foot long at 2-ohm stable bridged at 600W, you can see why I tend to recommend this for a value sub stage amp. It'll power my ID10 quite nicely (and maybe even an IA Flatlyne further down the road). Even running in a 2-channel configuration, 125W should be more than enough for the average user.

The plan, as it stands, is to power the ID10 with this BA and the JBL MS comps on the Kenwood KAC-923 I received this weekend (courtesy of mr b ; ). I will post updates as they come along since I still have to point out some key things on this amp, but the toolbag is unfortunately in my car and I am le tired so I won't be showing any additional pics tonight.

Stay tuned, folks.

Dtrom
02-05-2013, 12:27 AM
Dude, it's a $5 difference, why didn't you buy it new!?!? Lol. Looks like a solid amp. I like Boston.

neo_styles
02-05-2013, 12:28 AM
Dude, it's a $5 difference, why didn't you buy it new!?!? Lol. Looks like a solid amp. I like Boston.

I bought the refurb so you could buy the new one, man! I don't mind used equipment.

---------- Post added at 08:28 PM ---------- Previous post was at 08:28 PM ----------

Plus if it craps the bed, I'm sure I'll get a new one as a replacement.

Dtrom
02-05-2013, 12:30 AM
I bought the refurb so you could buy the new one, man! I don't mind used equipment.

---------- Post added at 08:28 PM ---------- Previous post was at 08:28 PM ----------

Plus if it craps the bed, I'm sure I'll get a new one as a replacement.

Lol just messin with ya. Looks solid. What's it replacing?

neo_styles
02-05-2013, 12:32 AM
Lol just messin with ya. Looks solid. What's it replacing?

I'm pulling out the Eclipse 5-channel. Need someone to look at it because in 5-channel mode, the bridged output on the left side goes to 0V. Plus I want something that actually fits behind the rear seats so I can mount the sub forward-facing.

neo_styles
02-05-2013, 12:33 AM
Honestly, if I'm impressed enough with this one, I'll snatch up another two or three and just run them on everything. They're so small for what they put out. Hard to believe it's a class A/B.

mr b
02-05-2013, 01:06 AM
Nice buy man.

neo_styles
02-05-2013, 01:07 AM
Nice buy man.

Thanks. I'd say you can get one, too, but I think you're running out of shelf space in the garage lol.

mr b
02-05-2013, 01:13 AM
Yes and my girl is wondering why I am not selling or using the amps. STANDBY FOR A LONG SALE THREAD!

neo_styles
02-05-2013, 01:16 AM
Yes and my girl is wondering why I am not selling or using the amps. STANDBY FOR A LONG SALE THREAD!

They never understand...but yeah, that 'Stang needs to have some breathing room.

mr b
02-05-2013, 01:23 AM
LOL yes, or I gotta sell it to feed my habit.

dragnix
02-05-2013, 09:38 PM
That's a big amp fyi

neo_styles
02-08-2013, 10:32 AM
That's a big amp fyi

Lol not really. Gotta remember it's a class A/B that actually was thought enough about during the design phase to include forced cooling. It's not tiny, but in comparison to competing models, I'd say the size is right.

dragnix
02-08-2013, 08:14 PM
Lol not really. Gotta remember it's a class A/B that actually was thought enough about during the design phase to include forced cooling. It's not tiny, but in comparison to competing models, I'd say the size is right.

you didn't specify class A/B

neo_styles
02-08-2013, 08:19 PM
you didn't specify class A/B

Fair enough. Did now. Was going to install it today, but weather stinks and the whole family's coming down with a cold. Hopefully this weekend and I intend to break out the Canon 60D for shots and a video.

dragnix
02-08-2013, 08:22 PM
Fair enough. Did now. Was going to install it today, but weather stinks and the whole family's coming down with a cold. Hopefully this weekend and I intend to break out the Canon 60D for shots and a video.

yea, I have a pretty big A/B 4ch. i'm going to put in the ride. Yea, this rain came out of nowhere. I wanna put my HIDs in tomorrow. Hopefully I get that done then I'll put my sounds in. Now if only JBL takes care of my MS-8, the bastage

neo_styles
02-08-2013, 08:25 PM
Now if only JBL takes care of my MS-8, the bastage

Wutchutalkinbout Willis?

---------- Post added at 04:25 PM ---------- Previous post was at 04:25 PM ----------

And don't know about Downey, but Burbank was getting slammed with rain and hail a few hours ago.

dragnix
02-08-2013, 09:04 PM
Wutchutalkinbout Willis?

---------- Post added at 04:25 PM ---------- Previous post was at 04:25 PM ----------

And don't know about Downey, but Burbank was getting slammed with rain and hail a few hours ago.

had an Ms-8 and the display went bad on me. Sent the display in and didn't have tracking (stupid) and they said they didn't receive it. I emailed them and they said to send the whole thing in and they'll replace it. Sent it in with tracking this time, tracking said received, called them and they said they never got it. They said to give them the tracking and they'll release it from the warehouse, that's the last I heard from them.

Rain yes, but hail, hell no

neo_styles
02-08-2013, 09:06 PM
had an Ms-8 and the display went bad on me. Sent the display in and didn't have tracking (stupid) and they said they didn't receive it. I emailed them and they said to send the whole thing in and they'll replace it. Sent it in with tracking this time, tracking said received, called them and they said they never got it. They said to give them the tracking and they'll release it from the warehouse, that's the last I heard from them.

Rain yes, but hail, hell no

That's freakin' weird.

Dude Harmon International HQ is here in LA. I'd just start knocking on doors. Try PMing Andy over on DIYMA. He might be able to help you out faster.

dragnix
02-08-2013, 09:10 PM
That's freakin' weird.

Dude Harmon International HQ is here in LA. I'd just start knocking on doors. Try PMing Andy over on DIYMA. He might be able to help you out faster.

It's in Northridge, but the email I got was to send it over to their HQ in Atlanta, so I have no idea wtf is going on with my shiz

neo_styles
02-08-2013, 09:13 PM
It's in Northridge, but the email I got was to send it over to their HQ in Atlanta, so I have no idea wtf is going on with my shiz

Lulz draft up a power of attorney and I'll go bust down Northridge's doors. That like five minutes away from here.

dragnix
02-08-2013, 09:15 PM
Lulz draft up a power of attorney and I'll go bust down Northridge's doors. That like five minutes away from here.

lol, that sounds like a plan

neo_styles
02-08-2013, 09:16 PM
lol, that sounds like a plan

Seriously, though, I'd plan a trip up to Northridge HQ and bring the tracking info and all the emails you've maintained. Could work out well.

dragnix
02-08-2013, 09:20 PM
Seriously, though, I'd plan a trip up to Northridge HQ and bring the tracking info and all the emails you've maintained. Could work out well.

hmm...we shall see, i'll contact them one more time to see how that goes. Thanks for the offer

KnightWhoSaysNI
02-09-2013, 07:37 PM
updates?

neo_styles
02-09-2013, 07:39 PM
updates?

Mother in law took the son today so I've been spending time with the wife. Sadly, I probably won't have anything until tomorrow.

KnightWhoSaysNI
02-09-2013, 09:29 PM
Ahhh just curious, enjoy your time!

neo_styles
02-09-2013, 09:45 PM
Ahhh just curious, enjoy your time!

Thanks bud. Big fan of the username btw. Clever.

KnightWhoSaysNI
02-09-2013, 10:09 PM
HAHA! Thanks!

neo_styles
02-10-2013, 11:54 PM
OK Quick update to those who actually care about this thing. I managed to install the Boston today and got everything wired up except for the sub. Just want to verify the internal wiring, but the amp gain is already set to 300W by DMM so all I'll have to do it pop the sub box back in there and wire it up. Connections are pretty simple on this amp, provided you have a set of allen wrenches. Turns out the clearance on my bit set wasn't deep enough to bite onto the power or the speaker connections, so you will have to use hex wrenches. For those who buy new, it's included. But if you're like me and got the refurb, plan to provide one of your own (guess that's where the 5-dollar difference comes from. Additionally, you will need a female quick disconnect to attach the remote turnon lead. Looks like this (photo courtesy of SE):

http://i.seimg.net/images/865444/big/fd110b.jpg

Btw, that package of quick disconnects I displayed was 5 bucks for 100-count. Great for shops *hint hint and shameless plug*

Anywho, back on track. The largest power wire this thing is going to accept is 4 gauge. I used the 4ga Silver-tinned OFC from AudioTechnix and found it both extremely flexible and easy to work with. Installation would be much easier if you had a little solder and tinned the tips to keep them from fraying off, but I didn't have a soldering iron at my disposal. I'm starting to learn it's an invaluable tool. Anyway, I ended up twisting the strands as tight as I could and then kinda "screwing" the wire in to the terminal to keep from having any issues with fraying. The end result was clean enough for my tastes (though it won't translate on photos; I haven't secured down my distribution blocks).

Once I got the battery reconnected and juiced up the amps for gain adjustment, I learned the Boston has GOBS of power on tap. I would go so far as to say it's overrated, but would rather wait until I have an oscilloscope to confirm the max unclipped output. Like I mentioned before, I simply dialed in for an end result of 300W at 2ohms since that keeps me well in line to what I feel comfortable feeding my ID10.

Listening tests and photos will follow. I, unfortunately, did not get to take photos because I took the 60D down without the memory card. I owe you guys a walkaround, though, so stay tuned.

neo_styles
02-12-2013, 01:07 AM
Got the sub connected today. SUCCESS! Luckily I had some ring terminals left over from a previous project because I forgot the bolts on my SMS box were 1/4", not 1/8". Anywho, with everything hooked up and playing, I realized that my gain estimate of 300 was conservative at best and dialed up just a hair more (so probably around 350W right now) as well as enabled the HPF and set it for around 28Hz to act as a subsonic. I set the LPF on my HU to 63Hz with a 24db/oct slope (Love this Eclipse). The results is nice, tight, punchy bass that I was previously unable to obtain from any of my past amps. It's almost enough to make the claim that A/B power on subs really is a different sound, but I attribute it more to the fact that the ID10 is getting real power now.

So at this point, it's going to be a lengthy process finding the fair balance between keeping the bass punchy without causing the tweeters to go sibilant. This will be fun.

neo_styles
02-12-2013, 01:20 AM
Oh another note:

I was wondering why my sub wasn't playing at first and checked the connections only to find the negative wire to the amp had come loose. Make sure you can use an allen key long enough to put the short side into the hole for the screw and still get purchase on it. And those using 10ga wiring will also have fun keeping the wire from fraying as you insert it. I would follow the same practice of tinning the wire with solder just to keep the ends together.

gckless
02-12-2013, 01:23 AM
Nice review man.

neo_styles
02-12-2013, 01:25 AM
FINAL NOTE in my rant, I swear. Let this be a lesson learned that it is a HORRIBLE idea to try moving a giant sub box to fit in next to my amps with the seats still raised. The Kenwood amp took a nice sacrifice from my left pinky:

https://lh5.googleusercontent.com/-aLSCO3IQzQ4/URnRngcIY7I/AAAAAAAAGrk/6yzOMOQnI9I/s821/IMG_0329%5B1%5D.JPG

---------- Post added at 09:25 PM ---------- Previous post was at 09:24 PM ----------


Nice review man.

Thanks. I plan to do a video review using the 60D to hopefully get some of the sub to play through and attach it to the MS62c review thread, but really have to tweak this EQ first.

rugdnit
02-12-2013, 01:58 AM
Sorry if I missed this-- are you running a final impedance of 2 or 4? I gotta admit I have been peddling back through a good amount of threads where posters are asking if they should run a 2125 / 2200 or various Class D's at 1 Ohm. Brutal- Not much for SQ at 1 Ohm. I have run the new Zed Minotaur at 2 / 4 and Kronos at 4 and it was extremely powerful and articulate. Much better than most run of the mill class D blocks at 1 ohm and 1.21 gigiwatts. These Bostons are tough to beat and the pricing at sonic is redonk. I snagged 2 of the 2200, 2 of the 2125 and found a refurb direct from boston on a 4100. Lovin it. These amps are being passed over in the race to go small class D. If you have the room I highly recommend these-- Very Clean and powerful.

neo_styles
02-12-2013, 02:04 AM
Sorry if I missed this-- are you running a final impedance of 2 or 4? I gotta admit I have been peddling back through a good amount of threads where posters are asking if they should run a 2125 / 2200 or various Class D's at 1 Ohm. Brutal- Not much for SQ at 1 Ohm. I have run the new Zed Minotaur at 2 / 4 and Kronos at 4 and it was extremely powerful and articulate. Much better than most run of the mill class D blocks at 1 ohm and 1.21 gigiwatts. These Bostons are tough to beat and the pricing at sonic is redonk. I snagged 2 of the 2200, 2 of the 2125 and found a refurb direct from boston on a 4100. Lovin it. These amps are being passed over in the race to go small class D. If you have the room I highly recommend these-- Very Clean and powerful.

Wish I had the budget atm for a new Zed, but the Boston has actually done pretty well for me. I'm running it at 2 ohms bridged, to answer your question.

Yeah, it really confuses me as to why as well. The 2125 is about a small as a lot of the consumer-level Class D amps I've come across, but I imagine it probably also has to do with wanting a system with less strain on the car's electrical.

After my experience with this as a monoblock, I'm tempted to play around with it as a 2-channel. The OS Kenwood is pretty impressive, but I feel like I should stock up on a few of theses 2125s while they're still being distributed instead of having to find them on the used or NOS market.

neo_styles
02-12-2013, 02:27 AM
Just a FYI, everyone, the Boston amps are selling out quick on Sonic Electronix. I just went on to see if they still had the GT2200 and it's no longer listed. The 275 and 2125 still are, though. 80 bucks for the 275.

neo_styles
02-12-2013, 02:27 AM
Just a FYI, everyone, the Boston amps are selling out quick on Sonic Electronix. I just went on to see if they still had the GT2200 and it's no longer listed. The 275 and 2125 still are, though. 80 bucks for the 275.

kushy_dreams
02-12-2013, 02:43 AM
I love how Boston amps have the slider mounting tabs so you can mount them on a variety of different sized surfaces

rugdnit
02-12-2013, 02:44 AM
I don't find these Bostons to be the current hogs that some A/B amps can be.

neo_styles
02-12-2013, 02:45 AM
I don't find these Bostons to be the current hogs that some A/B amps can be.

Neither do I. Kinda surprised by the power output for something only fused at 40A. Total fusing in my car is 80A right now. Never thought I'd say that.

neo_styles
02-12-2013, 02:46 AM
I love how Boston amps have the slider mounting tabs so you can mount them on a variety of different sized surfaces

Definitely. Just wish they weren't made of plastic. Making sure I drilled down in the right spots was hard since I didn't want to break one of the tabs. Kept having to check and recheck that I was in the right spot.

neo_styles
02-12-2013, 02:47 AM
dbl

rugdnit
02-12-2013, 10:35 AM
I don't know what the exact makeup of the feet are, but they appear to be a little more than your standard HDPE. It's surprising what they can come up with. This coupled with Aluminum feet not sliding / wearing well over the long term it was probably an excellent choice. If the amp was engineered properly and it certainly seems so-- every piece / part serves a purpose.

E-Rock
03-08-2013, 05:48 PM
Just picked up a GT-2125! I will be using it for my mids/highs though. Probably a set of MS-62c's as well.

I haven't been able to hook up the amp to anything, but I really am impressed with it. For having a fan and 125x2 it's about the same size as the JBL GTO 752 I used to have. The only thing I don't care for is the cover plate for the wires and crossovers. Just more screws to undo, not a big deal since I usually set and forget and it helps clean up the amp's appearance.

If I can finally work up the nerve to mess with my new truck and install a system or at least do the wiring, i can finally see what the amp is capable of. I hate having equipment sitting around while I have been dealing with Ford OEM speakers.

rugdnit
03-08-2013, 08:22 PM
Just picked up a GT-2125! I will be using it for my mids/highs though. Probably a set of MS-62c's as well.

I haven't been able to hook up the amp to anything, but I really am impressed with it. For having a fan and 125x2 it's about the same size as the JBL GTO 752 I used to have. The only thing I don't care for is the cover plate for the wires and crossovers. Just more screws to undo, not a big deal since I usually set and forget and it helps clean up the amp's appearance.

If I can finally work up the nerve to mess with my new truck and install a system or at least do the wiring, i can finally see what the amp is capable of. I hate having equipment sitting around while I have been dealing with Ford OEM speakers.

Enjoy!

E-Rock
03-08-2013, 11:37 PM
oops.

iball1804
05-26-2013, 03:27 PM
I bought a GT-2125 from Sonic Electronix a couple months ago for $109.99 and absolutely LOVE it.

I wanted to buy another one for an upcoming build, but it's either discontinued or out of stock everywhere! Anyone have any ideas on where I can find another one for a comparable price?