Some mod ideas for my AOR30

[Pierre]

It has a very fuzzy, unfocused bass and overall sound, which I really don't get.
I'd like, if possible, to smooth things out, and have simply more solid, chugging bass.
Right now it has 4 12AX7 (2 pre, 1 PI and one reverb driver) and 2 6V6s.

I was thinking of disconecting the reverb circuit and its many buffers, decreasing the gain on V1's first half, and maybe increase V2 (which is the gainboost)'s gain (changing the bias resistor) to make up for it. This would also transform it into a more manageable '2 channels' amp.
But I believe I may also have to change some of the tone stock...
If anyone can help me, I'd be very happy. Thanks!
Also, since the 6V6s use the same socket as EL34s and 6L6s, could I mod the amp for 2 EL34s? They wouldn't run at their best, but with a new OT I could maybe bring the amp to 50W as well, in a safe circuit? Or would I die?
Thanks!

[Baltar]

Re: Some mod ideas for my AOR30

i had an aor 30 top, an older one without reverb.
i think i know, what you mean with the bass. i don't think,
that removing the reverb will change this, because mine
sounded the same way.

i have seen a 6v6 to el34 conversion kit some day, if i find
the link agaoin, i post it

[Animal]

Re: Some mod ideas for my AOR30

I have an AOR-50 head running into a 1x12 open back cabinet and the sound of the bass is almost exactly what you've described. While I'm also considering getting the amp modded for a tighter sound I wouldn't blame it entirely on the amp if your combo is of an open back configuration. In open backs, a lot of the bass response is disfused, giving it a broader or "unfocused" sound.

Someday, when I have enough money I'm going to get a custom made closed back 2x12 cab. If that doesn't make the Laney sound much tighter then I'm going to get it modded by an amp tech. Possibly a variation on what Kevlar3000 that posts here has done to his own AOR-50:

I have upped the value of just about all of the caps. More bottom, and warmer character this way. I swapped the 50+50 can cap in the pre section with a 32+32. Gives it a more vintage vibe. Softer around the edges. I clipped the cap off of the master volume control and added a 470K resistor in its place as well as clipped the cap off of the pre gain. This tweak made an amazing difference with the hi gain channel, more bottom, earlier breakup and much more natural response. I put a .68 cap on the presence pot, instead of the .1. ( The George Lynch tweak) I also use a 12AT7 in the 4th tube position, the furthest to the left. Really opens up the hi gain inputs distortion.
This amp now sounds almost identical to an early 70s metal panel Marshall, it is no longer an 80s sounding amp. It is warmer and bigger, still has plenty of gain but with true old school flavor. I am amazed at how far this head has come. It now is right there with my vintage stuff.

Mine is a 6 knob version, I have never messed with the 8 knob. These amps are extremely picky about tubes, the wrong tube sounds REALLY bad, more than any amp I have owned. Good pre and power tubes make a huge difference, if you still have the original Siemens in it, you are winning 1/2 the battle. I also run mine with an attenuator, so I can really crank it. I tend to not use the boost switches on the hi gain channel, but on the low gain they sound really nice. Lots of variety with settings between inputs. I was shooting for a medium hot gain, 70s flavored machine and really have it where I want it now.

from this thread: https://forum.seymourduncan.com/show...t=58420&page=2

[Pierre]

Re: Some mod ideas for my AOR30

I have an AOR-50 head running into a 1x12 open back cabinet and the sound of the bass is almost exactly what you've described. While I'm also considering getting the amp modded for a tighter sound I wouldn't blame it entirely on the amp if your combo is of an open back configuration. In open backs, a lot of the bass response is disfused, giving it a broader or "unfocused" sound.

Someday, when I have enough money I'm going to get a custom made closed back 2x12 cab. If that doesn't make the Laney sound much tighter then I'm going to get it modded by an amp tech. Possibly a variation on what Kevlar3000 that posts here has done to his own AOR-50:



from this thread: https://forum.seymourduncan.com/show...t=58420&page=2

Mine's a closed back, and I already tried a variety of preamp tubes in V1 and 2 to check on the sound and smoothness. Unfortunately not much worked.

The bass IS tight. Just way too much, it lacks presense and chug, if you see what I mean.
I'll replace the filter caps and the big major caps in the circuit first.

[shredaholic]

Re: Some mod ideas for my AOR30

Lacking any knowledge of what your amp has inside it, I'd still suggest looking at the preamp cathodes - do they have bypass caps? If so, start trying lower value caps, the lower the value the higher the cut-off frequency will be for the sound that isn't at full gain for that stage. Therefore you get progressively less bass the more you lower the cap value.

If the relevant stages don't have bypass caps - add a bypass cap and turn down the gain slightly. The cap should boost the gain above the cut off frequency, giving the impression that there's less bass. To make the overall gain level the same as before, you just turn it down a bit.

[Pierre]

Re: Some mod ideas for my AOR30

Yeah, V1A/B and V2B have a bypass cap, along with their resistor.
After I change all the electrolytes caps, the plan will be to change the bias of the preamp tubes for less gain, and I'll try a slightly different voicing too.

Or I could just use the same values as on a JCM800 since the circuits are very similar

http://www.schematicheaven.com/newamps/laney_aor30.pdf

[wixedmords]

Re: Some mod ideas for my AOR30

Potty, the hard thing about amps of that age is that they need some work. They don't sound like they did 25 years ago. Most AOR's seem to have gone a bit fizzy over the years. I would have the caps done, that would be the first thing.

Have you thought about a 12AT7 in P1? Does it have a bias pot? You could try pushing the envelope right up to 70% and then try the other end of the spectrum, about 50%.

The question to me is, as it is with most amps of this age, do you like it enough to recap it? Only you know the answer to that.

But, as you likely know, very few amps out of the box are just "right" to one's ears. I had to work on my LC15 to get it there, I had a hard time re-speakering my LC30, then I got what I wanted, after a reapproach.

You may want to reapproach what you have for a speaker also. Just like in the sense of pickups, where a JB isn't the best fit for "EVERYTHING", you may want to reapproach your speaker in a new way. You might try thinking of smaller improvements adding up to a big change.

Overall, if it is an important amp to you, then reappraoch, put some things on paper, and map out a route. But, if you feel you are polishing a turd, you may want to start with something else.

[Pierre]

Re: Some mod ideas for my AOR30

Well... I don't feel it's a turd. And I can't buy anything else... nor can I afford a tech (if there even is one around...) so this seems like the best option. It'll give me the experience, be cheaper (if I don't die) and well... I like working on the darn thing

A full recap should straighten things up a little. When I play my POD through its poweramp and then speaker, it sounds great, so I doubt the speaker really is that bad. Maybe it can be improved but out of deduction, it's not the main problem. Thanks dude!

[wixedmords]

Re: Some mod ideas for my AOR30

I like moddin' them too Pott. I didn't mean any ill-will toward your AOR, just trying to get you to weigh how much you may end up putting into it to get it to where you want.

There are some who have boutique amps who still don't have the sound they have in their head. That's slays me.

I don't want you to think that I think it is a turd Pott, because you may make one change that just does it for you. But, I would hate to see you sink too much money into it to never see a result.

Anyway....

I vote for a recap, because that may get the fizz out, and I vote for a lesser gain preamp tube in positon 1. When I have done this, I find not only is the gain slightly reduced, but it gets a bit stronger mid flavor.

......that and 30 cents will get you a pack of Juicy Fruit.

[Pierre]

Re: Some mod ideas for my AOR30

Ohh sorry I didn't assume that you meant it was one, I just said this to mean that it is worth modding to me. And also because I have no other choices hehe...
Mhmmm fruits...


Oh... also, about the caps: which parts of the caps should I NEVER EVER UNDER ANY PRETEXT OR ELSE I'LL BE DEAD touch?
I'm guessing most of these electrolytes caps still carry a lot of current, I doubt they got depleted overnight.
Also once I remove them, how do I store them?
Or should I just empty them firsthand?

[Baltar]

Re: Some mod ideas for my AOR30

I have an AOR-50 head running into a 1x12 open back cabinet and the sound of the bass is almost exactly what you've described. While I'm also considering getting the amp modded for a tighter sound I wouldn't blame it entirely on the amp if your combo is of an open back configuration. In open backs, a lot of the bass response is disfused, giving it a broader or "unfocused" sound.

i ran mine through a 112 3/4back

[wixedmords]

Re: Some mod ideas for my AOR30

Ohh sorry I didn't assume that you meant it was one, I just said this to mean that it is worth modding to me. And also because I have no other choices hehe...
Mhmmm fruits...


Oh... also, about the caps: which parts of the caps should I NEVER EVER UNDER ANY PRETEXT OR ELSE I'LL BE DEAD touch?
I'm guessing most of these electrolytes caps still carry a lot of current, I doubt they got depleted overnight.
Also once I remove them, how do I store them?
Or should I just empty them firsthand?

I have never done a cap job Pott. But, I believe it would be good thought to test everything (multi-meter)you are about to touch in a chassis. I know there are good instructions out there on draining and replacing caps, or many of the good people of this amp forum may be able to give you some direction.

I guess I should start calling you the name you use on this forum, huh?

[Pierre]

Re: Some mod ideas for my AOR30

Yeah, I still don't know who you are on the HC forums
I got a website explaining how to drain the caps, but I won't get into it for a while I think. Maybe this summer if I end up doing it. Thanks dude!

[idsnowdog]

Re: Some mod ideas for my AOR30

I thought only mine sounded like that? I had one years ago and got rid of it quick. What pissed me off was that I was always turning the gain and bass down the longer I played because it kept getting mushier.

[wixedmords]

Re: Some mod ideas for my AOR30

Yeah, I still don't know who you are on the HC forums
I got a website explaining how to drain the caps, but I won't get into it for a while I think. Maybe this summer if I end up doing it. Thanks dude!

HC is read only, and only on occasion. I haven't got time for the pain.