How much bass can my M100B speaker handle???

[andylevine]

I have a MRA3-L6 amp from a 100C in my 100B and in general it sounds pretty darn good.  I was playing with the bass settings on the amp, and any time I turn it up past 1 and play a bassy song, I get pretty bad distortion.  Sounds like the speaker is "flapping" and it gets pretty muddy.  Having no reference point as what one of these boxes SHOULD sound like, I was wondering if I was just driving it too hard, OR is the speaker ready for some maintenance??   Was the 100C speaker the same as in the B, or was it made to take more of the low end??  Would I benefit from a reconing, or should I save my money and leave the bas settings on 1??

Thanks for the advice
Andy

[Ron Rich]

Hi Andy,
Amps are comparable--except for the -3 has AVC. Did you do anything about that ? If not the VC "curve" will be incorrect, which I THINK, may cause that ?? -- Speakers are the exact same--Which cart/needles are installed ? Was amp mod-ed for this cart. ?

[andylevine]

Ron, I have a relay on order to deal with the squelch issue, but it isnt installed yet. I'll retest after I do that and see if it is any better. I suppose I could test by just grounding out pin 3. Will do that in a bit and report back.

[Ron Rich]

Andy,
No relay needed-- either add the switch ( my preff.) or remove the AVC tubes--
Ron Rich

[andylevine]

I assume by "add the switch" you are referring to the MS contact you mention in 'The Guide'? More correct for sure, but I guess I would need longer screws as well to add it to the block. You have the spare parts to make one up??? I'd gladly reimburse you for your time and parts!

[robnyc]

Andy, this topic has come up in various discussions regarding Seeburg AGC's.

IF you are using the mono redhead AND using mono spike styli ALONG with 1960-s -70's records there is s significant chance that some of these records are driving the AGC to the point where it loses control and serious bassy distortion occurs.

Records became -much- louder in the early 60's. This can cause the reactance tube (SK7 or BJ6) to have its G1 grid go positive with respect to the cathode. That is when the tube begins to draw grid current lose control.

Before going into possible solutions, let us know what you are using.

RobNYC

[Ron Rich]

Andy,
Yes--the MS contacts--no I do not have any in stock--screws are 5-40x2 inches--Check with your pinball parts suppliers for contacts--Ron Rich

[andylevine]

robnyc, I'm using a reconditioned/rebuilt Blackhead with the stereo (L shaped) needles. Mostly mid/late 50s-early 70's . The 50's record DO sound better in general, but a lot of my sisties are not in the best of shape, even cleaned up.

Ron, thanks for the info....will look online

[Ron Rich]

Andy,
Be sure "R-1" is a 10k-- Ron Rich

[andylevine]

Ron, yep 10k...tested within tolerances. (on the MRA3, its R-7)