AMPEG BA108 with EMINENCE ALPHA 8a - Page 2

Woodstockz · #21 10-11-2012, 09:17 AM

Quote:

Originally Posted by gottliver

yep, i have somewhat the same story.

no farting at high volume, but distortion. not sure if it is the pre or amp clipping? when i get the volume past 1pm it starts to get fuzzy. is it any louder? thats debatable, but again, no farting, distortion.

Yes, I have heard and mentioned distortion at very high volumes. That is not the same as cabinet buzz.

gottliver · #22 10-11-2012, 02:16 PM

agreed. the alpha8 sound very good.

Woodstockz · #23 10-11-2012, 02:53 PM

Quote:

Originally Posted by gottliver

agreed. the alpha8 sound very good.

Once you upgrade the speaker, other issues/flaws surface. Since you can crank it higher without the speaker farting, then you hear the amp distort.

It's like if you get your car painted. The paint looks great, but then you notice that the molding is rusted, the windshield is pitted, the rims are scrapped up, the headlight lens is faded...

redhed · #24 10-11-2012, 05:21 PM

The speaker is an awesome upgrade to already great amp, but its not going to transform the BA108 into a gigging machine - just a BETTER practice amp......

gottliver · #25 10-11-2012, 05:35 PM

Yep, BUT, the distortion is actually quite usable. It it sounds good. I gigged with it 3 times already in stock format with my DB and 2 guitar players/singers. No drums or keys. Held its own very well. Sat nite will be the first gig with the alpha8.

redhed · #26 10-11-2012, 05:38 PM

Quote:

Originally Posted by gottliver

Yep, BUT, the distortion is actually quite usable. It it sounds good. I gigged with it 3 times already in stock format with my DB and 2 guitar players/singers. No drums or keys. Held its own very well. Sat nite will be the first gig with the alpha8.

SWEET! I love that little amp!

redhed · #27 10-21-2012, 07:40 PM

The mod is COMPLETE! Thanks to the nice folks at Eminence, who sent me a nice EMINENCE inside badge fo my BA108 - for free!!!

Woodstockz · #28 10-21-2012, 07:44 PM

Quote:

Originally Posted by redhed

The mod is COMPLETE! Thanks to the nice folks at Eminence, who sent me a nice EMINENCE inside badge fo my BA108 - for free!!!

Sweet!!! Where did you get the badge? I want one.

redhed · #29 10-21-2012, 07:56 PM

Quote:

Originally Posted by Woodstockz

Sweet!!! Where did you get the badge? I want one.

I just emailed Eminence and they sent me one! Crazy.... super nice of them.

warwickbass99 · #30 01-05-2013, 09:51 AM

My question, there is a string on the ampeg which I think you can take out the screen. How do you take out the screen of the ampeg to get to the speaker, also, does installing the eminence alpha 8a require sodder?

redhed · #31 01-05-2013, 09:59 AM

Quote:

Originally Posted by warwickbass99

My question, there is a string on the ampeg which I think you can take out the screen. How do you take out the screen of the ampeg to get to the speaker, also, does installing the eminence alpha 8a require sodder?

That little tab is so you can pull the grill cloth frame off, it just pulls out. The ALPHA 8a just screws back in with the same 4 screws used to hold the original and no, there is no soldering.

tayal01 · #32 01-25-2013, 03:18 PM

I've just completed mine.

1. Re-glued all wood joins and seams, including inside the amp chassis which appeared to be poorly done at the factory.
2. Glued down factory batting
3. Lined speaker cabinet with a half pound of Acousti-Stuf.
4. Installed new Eminence Alpha-8A (BTW: if you are researching this, don't order an Alpha-8MRA! Even though the Eminence website specifically mentions "bass guitar" it's for a non-ported enclosure only)
5. Sent email off to info@eminence.com to get a cool "Eminence Inside" badge like RedHed.

It is now louder, cleaner and crisper and I love it.

However, I'm experiencing a considerable amount of what must be cabinet buzz at high volumes. Especially on the G octave (15th fret on the E string) which must be the resonant frequency of the cabinet. I can't quite isolate which part of the cabinet is generating the noise but I'm on a mission to find out what it is and fix it.

I can also hear a very slight distortion or buzzing in the signal which I don't think was there before putting the Alpha-8A in. It could have to do do with the guitar, Fender Jazz, or the cable. I'll look into that too.

tayal01 · #33 01-25-2013, 04:40 PM

Quote:

Originally Posted by tayal01

I've just completed mine.
However, I'm experiencing a considerable amount of what must be cabinet buzz at high volumes. Especially on the G octave (15th fret on the E string) which must be the resonant frequency of the cabinet. I can't quite isolate which part of the cabinet is generating the noise but I'm on a mission to find out what it is and fix it.

I think I've found it. The right side of the front baffle, next to the port, appears to have not been glued. I can move it slightly with my hands. The other three sides - top, left and bottom - are all solidly attached. At first I thought it was the cardboard port itself until I noticed the very slight play in the baffle. I've glued it inside and out (I had to remove a couple of mm strip of the cover material to get wood on wood contact).

Woodstockz · #34 01-25-2013, 04:57 PM

Quote:

Originally Posted by tayal01

I think I've found it. The right side of the front baffle, next to the port, appears to have not been glued. I can move it slightly with my hands. The other three sides - top, left and bottom - are all solidly attached. At first I thought it was the cardboard port itself until I noticed the very slight play in the baffle. I've glued it inside and out (I had to remove a couple of mm strip of the cover material to get wood on wood contact).

tayal01,

Can you post a picture of that, for just in case someone else has the same problem?

Thanks.

Woodstockz · #35 01-25-2013, 06:17 PM

Instead of just putting glue on the seams, you should glue in 1/2 inch by 1/2 inch strips along the seams. That gives the glue something to bite into.

tayal01 · #36 01-25-2013, 07:47 PM

Quote:

Originally Posted by Woodstockz

Instead of just putting glue on the seams, you should glue in 1/2 inch by 1/2 inch strips along the seams. That gives the glue something to bite into.

Totally agree. However, I wanted to be sure my theory was correct so I proceeded with the bead of glue on the seams approach to see if it really made a difference. Gave it a couple of hours to harden and popped the Alpha back in for a test...

...No rattle or buzz! WooHoo!

I've attached a picture to show the part of the cabinet that needed gluing. You can still see some of the white glue still drying.

It won't hold for ever so my approach for a permanent fix, rather than adding additional wood bracing is to put a wood screw through the front baffle into the existing wood brace which appears to fixed firmly. I suspect they failed or neglected to nail gun the baffle on this side or to glue the seam prior to nailing.

Disappointing. I can imagine some young bass player getting one of these, being unhappy with the apparently poor sound quality and never wanting to buy another Ampeg again. The importance of good QA!

Bassquest · #37 01-25-2013, 08:02 PM

My BA108 rattled on certain frequencies too so I wedged flat pieces of steel plates in each front corner to tighten it up and it went away. Before doing that I found that putting the amp on it's side and sitting on it would also make it go away.

Hock · #38 01-25-2013, 11:56 PM

I'm interested in this amp - how to connect an Ipod to this amp? It has a CD type input? You need some adapter?

tayal01 · #39 01-26-2013, 05:24 PM

Quote:

Originally Posted by Hock

I'm interested in this amp - how to connect an Ipod to this amp? It has a CD type input? You need some adapter?

It has an auxiliary input right on the control panel with it's own volume control. You'll need to get yourself a mini-jack to stereo RCA cable. The auxiliary signal comes through the speaker (and the headphone).

tayal01 · #40 01-31-2013, 05:17 PM

Last night it had its first outing. I took it along to our Jazz combo rehearsal - Guitar, Keyboards, Acoustic drums and Bass. The rehearsal room is small, the guitarist has a Fender Blues Junior which is only 15 watts I think, but quite capable of being loud!

Here's the interesting part. The keyboard player had no amp so I plugged him into the Active input (-15db) and myself into the Passive input and that was our setup for the night. My little modded BA-108 performed like a champ! No one even noticed any difference. I'm really liking this little amp (if only they would glue them up properly at the factory!) and really pleased I decided to go with this project.

Next steps: Op-Amp rolling, precision port and power supply upgrade as per Woodstockz Coffeeshop Micro Rig Project.

ps: I got an email from Eminence to say my "Eminence Inside" badge is in the mail. :-)