How to get more Bass from a Orthophonic Reproducer

[Victrolaman]

Hi all, havnt been on in a while. I found a nice unrestore Brass Reproducer the other day, its air tight and sounds ok, but there isnt much bass from it? i have 3 other brass reproducers 2 i restored myself and they sound very nice. My question is how can i get more bass out of the reproducer? the ball bearing are tight in there, all original, has the original back rubber flange on it.
Im a fond beleiver if its not broke leave it alone :)Would replacing the gaskets with new rubber or what they make the news ones out of give it more bass? Also i noticed on this one to, at the end where you insert the needle, that parts not in the middle but off to the side touching the side of the housing? needle bar is in the middle and straight but the end where the nedle goes is touching the side, I forget what that parts called. Should that be in the middle to?
I have restored my other 2 brass repeoducers the other 1 i have is original to the machine and 2 pot metal ones all with good results, but this one i just picked up lacks good bass Founsd this at a yard sale in a box of misc stuff, paid 5 dollars for it

[syncopeter]

IT is most probably a bit of a broken soft tone needle that has stuck. The needle not really sitting right may lose you the bass. bass.

[Orthophonic]

This sounds kinda odd but you can place your fingernain on the needlebar where it is over the body of the soundbox and then seal your lips over the neck of the soundbox where it connects to the tone arm or taper tube. Gently push and pull air pressure into and out of it; there should be no air leakage if it is all good. Loss of air means a crack or hole with a corresponding loss of bass. For some reason, I have noted that some later versions of orthophonic and especially HMV versions have crimps on the outer convolution of the diaphragm before it goes to the more flexible edge. This wah undoubtedly done to increase the center rigidity of the diaphragm but I have notuced that most of the crimps have cracks in them which causes air leaks. For otherwise good diaphragms, I have cheated and placed tiny drops of superglue over the cracks to seal them; this is not a real good repair for parts of the diaphragm which flex normally. Hope this helps!

[Victrolaman]

hi,
Yes its air tight and its a brass one there are no damage anywhere, i just didnt know if there was a way to increase bass responce is all, new gaskets or what have you.

[estott]

If it's still got the original gaskets they probably need replacing.

[Victrolaman]

hi, yes the original gaskets are still there, will new ones increase bass responce? i did change the ball bearings, new back rubber flange and thats all i did.
What are the nrew gaskets made out of?

[Orthophonic]

If there is no air leakage, the old gaskets are doing their job. The new ones that I have are of rubber and very thin; the old ones were paper sealed with shellac, I think. I'm not sure about that.

[MicaMonster]

The biggest problem with aged Orthophonic reproducers is that the mounting flange, which was originally GUM RUBBER, hardens up to something resembling black granite. The rubber replacement flange sleeves are softer, but not soft enough. What essentially happens is that low bass notes travel from the groove, up the needle, across the pivot bar (fulcrum) and to the diaphragm spider. Although this system is nearly ideal, some lateral force is indirectly applied to the soundbox body at the pivot. What happens here affects record wear as well as reproduction of low notes: the sound energy vibrates the soundbox and is solidly matched by the ZERO compliance of the petrified/hardened rubber flange, and is reflected back to the pivot bar to be transferred back to the needle/diaphragm. This creates LOUD & strident bass notes, not necessarily as natural and deep as one would like.

Everyone hears differently. Lots of people accept that the hard flange is JUST FINE. (much like collectors that say, "if it sounds like Uncle Josh, then its O-KEH!) Well, so be it. I replace ALL of mine with a butyl rubber centering ring, then hand-inject soft silicone around the original brass mounting sleeve. The idea is to isolate the soundbox from the tone arm, and allow the reproducer to vibrate and move with the record groove. This allows bass tones to reproduce with less stridency, with more vibrancy.

And, there you have it.

BTW- if you use rubber damping rings to hold your bearings in place, make sure they are holding the bearings GENTLY, and NOT with a lot of pressure, because that will create a clamping condition when the bearings are pushed IN too much, hindering free needlebar movement.

[Orthophonic]

I mentioned this elsewhere but the soft rubber mounts that provide the "spring" action on the keys of laptop keyboards is great for this. Most are mounted on a flexible membrane and have to be sliced off with an exacto knife; others are simply loose. Get the ones that hace an outer diameter that matched the inside of the bearing race as the center raised portion is pressed in by the dust cap. I kinda like them and they work well for me.

[pictureroll]

Who would have an Orthophonic mounting flange with soft rubber?
Jerry F Bacon, Dallas,Texas