New RTA 12B Owner Checking In

PolkFanVA

First wanted to say what a great group you all are, I recently purchased some RTA 21B's with peerless tweeters and this forum has provided a wealth of knowledge. I believe I need to do some tinkering with the filling to get my mid-bass/bass back (pressure testing tonight per many threads and speaking with a forum member on the phone) and moving the filling back up into the cabinet (again, thank you for the phone help). If/when funds allow maybe a recap but that is for much later. Upper range sounds fantastic but I can't squeeze any mid/bass out of them without hitting the loudness button and I am loathe to do that. I have maxed out what I am allowed to spend on audio for the year (ever?) according to my wife... Anyone with suggestions or tips for a new Polk owner please let me know. I already know that I hate the binding posts but I can live with them for now. The nostalgia alone makes these a worthwhile investment even if I can't get them sounding right, they remind me so much of my father and his speakers from when I was a kid.

F1nut

Welcome to Club Polk.

How far away from the rear wall are your speakers?

westmassguy

Welcome Matt

Faustin

Welcome. What are you powering them with? Amplifier, receiver??

PolkFanVA

Currently running a B&K Reference 50 pre into a B&K Reference 4420 amp, if the specs are to believed the amp should be putting out around 350W at 4ohms (I believe that is RMS but may be peak, the manual is a bit vague). Input is from a MacBook Pro with a Dragonfly Red USB DAC. Previously tried running them with a Sony TA-AX500 integrated but that is not rated to 4ohm loads and I was worried about burning something up.

PolkFanVA

Also as a follow up to my earlier post, I did a pressure check last night and both cabinets feel like they are sealed tight. I pushed the passive radiator in and both mid woofers extended and stayed out as long as I cared to hold the radiator in (if there was any reward movement for the 5-10 seconds that I held them it was not noticeable to my eye). I stuffed the filling back up into the top of the cabinet and response improved, still not where I thought they would be in terms of mid and low frequency response based on the reviews I have read. Not bad but I need to start saving my pennies I think. These are my only speakers at the moment so nothing else to compare them to so maybe I just have overly high expectations.

PolkFanVA

F1nut, quite a good distance. Towards the back portion of an estimated 30X30 garage, all open space around them and 8-10' from my sitting position and 10' or so separating the speakers. Both angled inward towards my preferred seating position. I can get some better measurements tonight with a tape, do you think that moving them closer in towards a wall would help? Building is fully insulated nut very little if any sound dampening (no carpet, wood on the walls, etc). There is a tractor behind them but I wouldn't think that would count for anything. Workshop/tractor shed/man cave basically.

F1nut

I'm not sure you'll ever get high fidelity in a large garage. Anyway, the speakers will produce better mids and bass 5 to 6 inches off the rear wall.

PolkFanVA

F1nut, thank you. I will see if I can either back them out that far or build a small wall (just above tweeter height) if that would help. 30' out feels like too far for good listening. Would carpeting and something on the walls help with fidelity do you think? I come more from a car audio background (and that has been years) so just really getting into the whole HiFi concept. I have read and read and always come away more confused and/or cloudy headed than before I started reading.

F1nut

In your listening position clap your hands once with authority. If you hear a slap echo the area is too lively and music will have an edge/hardness to it. Adding carpet, wall treatments, upholstered furniture will help tame that.

PolkFanVA

Thank you very much for the advice, so too much echo add more damping. If there is not much echo would some sort of backstop for the speaker cabinets be worthwhile to reflect some of the sound? I don't want to do a full wall but a 3'-4' high pony wall with drywall and insulation isn't out of the question. Then I couldn't back the tractor into anything breakable

F1nut

Regardless of the slap echo, the distance to the rear wall (behind the speakers) matters with vintage Polk speakers perhaps more than other speakers. The short distance helps to reinforce the bass response.

PolkFanVA

I will bring my whole rig into the house over the long weekend and see if that cleans things up. Man I hope it won't or I have really gone down a rabbit hole, I am guessing they will sound wonderful and then new pre and amp plus some new man cave speakers. Anyone have a couch I can crash on when my wife kicks me out for my new hobby

Faustin

PolkFanVA wrote: »

I will bring my whole rig into the house over the long weekend and see if that cleans things up. Man I hope it won't or I have really gone down a rabbit hole, I am guessing they will sound wonderful and then new pre and amp plus some new man cave speakers. Anyone have a couch I can crash on when my wife kicks me out for my new hobby

Heh, heh, heh, heh.

CH46E

The RTA12B can really dig low on bass. I'm always surprised. I have a feeling that huge area might be the issue. As F1 said about the clap test....... I did that in my room and it echoed for a good 1 to 1.5 seconds. After proper room treatments and bass traps the sound improved more than any other single upgrade.

CH46E

Got some pictures? ....... of the speakers of course.

PolkFanVA

I'll get some pictures later tonight when I get to go enjoy the space. Just had the kids in the garage having a dance party.

VSAT88

Welcome to C.P. !

PolkFanVA

Here is what I have

Left Speaker





Right Speaker





Right Mid woofers



Right lower crossover

PolkFanVA

From the stickers on the MW (I have opened both but only felt like taking them out of one cabinet last night...) these appear to be from 82 (at least the mw) Same year I was born, crazy.

Tony M

As Dave would say..."Minty"!

NICE set!

Jazzhead

Polkfan:

Regarding bass output, the experts here on the forum advise getting the polyfill up behind the midwoofers with absolutely none in the passive radiator area and they are very correct. Make sure the cabinet is sealed and none of the drivers/PR leak. Also my original RTA-12's seem to have come stock with much, much more polyfill than was "required" (apparently the installed amounts would vary?). My speakers ended up overdamped when I tried to get it all up there (restricted air flow). After many months of careful listening I ended up with the right amount - too much will overdamp (lifeless, sterile sound and loss of lowest bass octave). Get it just right and the bass will be tight (no boom), tuneful (not one-note) with realistic impact and slam (you should feel it); and will extend well into the lower octave. Repeatedly play well recorded tracks you are familiar with that contain a prominent low bass guitar part along with the kick drum and experiment. My 12's are 13 inches off the floor and about 15 inches from the wall and I have plenty of bass in a 14 by 26 ft. room. Your speakers are a better design, have a larger cabinet than mine and will produce even better bass.

PolkFanVA

Jazzhead, I spoke with Dave on the phone and he told me about the polyfill needing to be up top. It had all fallen in behind the PR so I folded up the pants leg portion and pushed that as high up as I could then used the two individual sections to help hold it all up. That helped a bit. F1nut also suggested where to place the speakers. I have them in an open garage/man cave not near enough to a wall right now. I moved the Right speaker to a wall last night and it was night and day. I am contemplating what to do to get things close to the wall. I don't want to rearrange my entire listening position but fear I will need to in order to get good sound from any speaker. Costco had a pre-black Friday deal on a Klipsch R-12SW for $149 so I went ahead and bought one. With the gain down very low and the crossover set a bit high it fills in the gaps nicely. But not as neutral as I would like on some tracks. Electronic and Drum and Bass sound nice with the sub in the system though I will just have to keep experimenting.

PolkFanVA

Also regarding the leaks/press test, any specific method? I must admit I have not searched extensively. I took video last night of each one just for fun. As long as I have my hand on the PR the mids stay extended. Starting to think it isn't a press and hold? If so then these couldn't be any tighter I don't think (20+ seconds and no leak down that I could perceive).

pitdogg2

Your speakers are sealed good. The mw6600 and mw6501 drivers have thicker felt dust caps and the hold air better. Newer mw6502,6503,6511,6510 all use a more open mesh dustcap that will allow air to come through voice coil gap and dustcap easier.

My SDA 1signatures also use mw6600 and mw6501 and i get a good 10-15 seconds that they stay out.

PolkFanVA

Great, I was worried I was doing this totally wrong and my cabinets might be leaky (although in the back of my mind I knew this was not the case). I am just overthinking everything these last few days. Slow days at work tend to let my mind wander and that gets dangerous.

F1nut

The Klipsch R-12SW is a ported Home Theater sub and a dirt cheap one at that. For a music system you want a good sealed servo sub such as Velodyne or Rythmik.

Jazzhead

Polkfan:

Dave and F1 have forgotten more about this business than most folks know. If you want to learn they will steer you in the right direction without fail.

PolkFanVA

F1nut, my budget is very restrained. My wife has had enough of this "nonsense" that I have recently gotten into. I was lucky to get the $150 for a dirt cheap sub. I know it is not ideal but I couldn't find a more cost effective way of getting any bass. Nothing good coming up used on my local (or extended search) CL. I didn't bother checking ebay as everything having to do with used speakers seems to be pickup only or shipping costs more than the item. I will eventually/hopefully have more options but without the CFO as it were on board I work with what I can.

PolkFanVA

Indeed they will, I appreciate the input that they have both given as well as everyone else who has contributed here or other threads helping me to better understand what to do and what direction to go in. I like to think I am a step up from a HTIB sort of guy but not much more knowledgeable than that. Decent amp, decent speakers, somewhere comfy to sit and that is all I thought that I needed. So much more to it than that I am finding.

Jazzhead

There's nothing wrong with doing things a little at a time (as funds allow). In some ways it is better because it gives you a chance to listen to and evaluate each step. Often the journey of "doing" a project (building a piece of furniture, restoring a fishing rod, assembling an audio rig etc.) is as rewarding as having the finished product itself.