Power Engine 60 type amp build

[sluglas]

I have a Zoom G5 that I use for gigging but only for effects. No amp models being used cause I gig with either a Roland Cube 80xl or a Fender Mustang III.
I had always wanted to get an old Tech 21 Power Engine 60 to try using the Zoom's amp models. The PE60's I could find were always too expensive.
So I figured I'd build my own.
I built a pine cab. Used an old Carvin VL10 75 watt speaker in an opened back config paired with an Eminence Alpha 8a in a closed back config.
I used an old Alesis RA100 stereo reference amp that puts out 65 watts/channel @ 8 ohms. Being a reference amp the Alesis has a very flat freq response.
I used a 10" and an 8" speaker to help keep weight down. I am almost finished so I haven't sound tested it just yet. I need to find the rack rails I misplaced.

 

[The Angle]

Eagerly awaiting preliminary test results.

 

[archetype]

If you did it again, a Tech 21 Trademark 60 would work. Ignore the amp's front end and plug your pedal into the effects return.

 

[NoTeleBob]

I had a similar idea... stereo "hi-fi" amp. Couple 12" cabs. Yesterday's FRFR today. Perfect to run off a modeling pedal.

 

[Tweeker]

Having owned a few Power Engine 60s and still a Trademark 10, I choose what you’ve made over that stuff any day!!

 

[Volcanicash01]

I have a Zoom G5 that I use for gigging but only for effects. No amp models being used cause I gig with either a Roland Cube 80xl or a Fender Mustang III.
I had always wanted to get an old Tech 21 Power Engine 60 to try using the Zoom's amp models. The PE60's I could find were always too expensive.
So I figured I'd build my own.
I built a pine cab. Used an old Carvin VL10 75 watt speaker in an opened back config paired with an Eminence Alpha 8a in a closed back config.
I used an old Alesis RA100 stereo reference amp that puts out 65 watts/channel @ 8 ohms. Being a reference amp the Alesis has a very flat freq response.
I used a 10" and an 8" speaker to help keep weight down. I am almost finished so I haven't sound tested it just yet. I need to find the rack rails I misplaced. View attachment 983730 View attachment 983731

I still use an ancient Zoom 707 for gigs occasionally. Great patches onboard, once you master the programming. Good products for their time.

 

[robinrockus]

I have a Zoom G5 that I use for gigging but only for effects. No amp models being used cause I gig with either a Roland Cube 80xl or a Fender Mustang III.
I had always wanted to get an old Tech 21 Power Engine 60 to try using the Zoom's amp models. The PE60's I could find were always too expensive.
So I figured I'd build my own.
I built a pine cab. Used an old Carvin VL10 75 watt speaker in an opened back config paired with an Eminence Alpha 8a in a closed back config.
I used an old Alesis RA100 stereo reference amp that puts out 65 watts/channel @ 8 ohms. Being a reference amp the Alesis has a very flat freq response.
I used a 10" and an 8" speaker to help keep weight down. I am almost finished so I haven't sound tested it just yet. I need to find the rack rails I misplaced. View attachment 983730 View attachment 983731

I have a newer Tech21 Power Engine that I really like. I plug PA signal into XLR on the back and run my guitar signal from my small tube amp to the 1/4 inch input on top. It can be used as a PA extension for a small space or a monitor in a large space. Versatile unit. Can be loud, yet clear and pleasant.

 

[sluglas]

Installed the rack rails, wired up the speakers for a quick test. Like most power amps it seems underpowered running a guitar straight into it. With a preamp it gets much louder. I tested it with a vox tonelab desktop modeler and it sounds great. The left channel with the 10" speaker gets much louder than the right side with the 8" .
It could be speaker sensitivity or a phase issue. I will have to verify that tonight. The Alesis manual states it puts out 75 watts per channel @8 ohms but I may have to have it cranked up to get that kinda wattage out of it.
The experiment continues.

 

[PhredE]

Installed the rack rails, wired up the speakers for a quick test. Like most power amps it seems underpowered running a guitar straight into it. With a preamp it gets much louder. I tested it with a vox tonelab desktop modeler and it sounds great. The left channel with the 10" speaker gets much louder than the right side with the 8" .
It could be speaker sensitivity or a phase issue. I will have to verify that tonight. The Alesis manual states it puts out 75 watts per channel @8 ohms but I may have to have it cranked up to get that kinda wattage out of it.
The experiment continues.

Earlier, on a whim, I looked up the sensitivity of each of those speakers.

The Carvin is 96.1db, the Emi Alpha 8a is 94db.
Plus, being a more PA/woofer type speaker, the Alpha 8 likely has a flatter curve not having the upper mids/highs that the Carvin guitar speaker might have. But, it probably does cover the low-end as well or better than the Carvin.

Carvin Audio Thiele/Small Parameters and Speaker Specifications

This page contains the Thiel/Small Parameters and speaker specifications for Carvin Audio replacement speakers and high frequency transducers. Find the values you are looking for here.

carvinaudio.com

Eminence Alpha-8A American Standard Series 8" 125-Watt Replacement PA Speaker 8 Ohm

8" Replacement Speaker, 125W RMS, 8 Ohms, 58Hz-5kHz

www.sweetwater.com

 

[sluglas]

Yes the Alpha 8a has a frequency response of 58hz-5000hz quite low for an 8" but the beauty of using a stereo power amp is I can adjust for speaker sensitivity. The 8" will probably be on 10 and the 10" will probably be on 7 to be equal volume wise

 

[ASATKat]

I owned two PE60s to drive my Kemper. But that shrunk down to one PE60. I was never happy, what sounded great at home didn't always sound the same on stage.

All that is gone, and now I have a Katana 100 Mk2, life is much easier. And my tone is great, home and on stage. So good that I focus on the music making and playing side of it all, and the tone is always there, no longer an issue.

And the Kat can serve the same role as the PE60 only better and more versatile. Not for the Kemper, I sold that so I could eat. I use my Yamaha MagicStomp for it's awesome unique effects mostly for psychedelic ambience, often going through the Kat, sometimes all by itself.

 

[sluglas]

Ok. I verified speaker phase. It seems the Alpha 8a's speaker sensitivity of 94db makes the volume lower than the 10" carvin. I have a couple of 8" speakers around will try instead though most 8" guitar speakers will only handle 25 watts or so.

Stay tuned.

 

[metalosophy]

Check your local CL, I bet someone is selling a 10" or two! Maybe even a busted/cheap 2x10.

 

[W.L.Weller]

Cabinet design, volume (of interior space) and porting will affect the frequency response and perceived loudness of that Alpha 8A.

You could also try flipping the whole thing over so the amp was on the bottom, getting the speakers a few more inches off the floor.