Peerless Tweeter question

kjm531

Hoping someone with a lot of Monitor listening experience can help me out here.
Just picked up a set of Monitor 5A's with Peerless tweeter and upgraded crossovers. This is my first set of monitors with the Peerless... I've had 5jr+ and 10B's and currently have a pair of 7C's with the SL2000.
When I first hooked them up, I was really curious to hear the tweeters so I was concentrating on them closely. They certainly didn't do anything to offend me, but they seemed really mellow. 'Distant' would be the word that keeps coming to mind. What I love about the monitor series is the balanced, natural sound - none of the one's I've heard would I ever classify as 'bright'. But this was extremely laid back. So I swapped in my 7C's and what a difference that made! Night and day as far as the 'volume' coming from the tweeter. Then I hooked up a set of Ascend Acoustics CBM-170 bookshelfs and the treble got even more detailed. When I switched back to the 5A's, it was as if someone put something in front of the tweeter to block the sound.
Yes, there is sound coming from the tweeter but it is very recessed.
So my questions are:
1) Is this normal?
2) Should the Peerless be as 'bright' as the SL2000?
3) Could whoever upgraded the crossover replace a cap with a wrong value?
4) Anybody in Detroit area want to do an A/B comp?

I printed out the crossover schematic from the sticky in this forum and plan to take a look this weekend. I've never done a crossover so I'm not sure if something will stand out even if it's wrong.
Sorry for the long post, but I really think something is wrong and I'd like to give these speakers a fair shake.... I was hoping they'd be 'keepers'.

PS- Related equipment is Rega Planar 2, Onkyo Integra M-506RS and P-306 dual mono amp / pre-amp.

Thanks in advance
Kevin

Outfitter03

Did the previous owner give you any details on what was done in the crossover upgrade? What components were replaced and specifically what brand of capacitors were use?

From your post count it looks like you are a relatively new member of PF. Welcome aboard. Here is a link that has been posted before that gives you some idea of capacitor sounds: http://www.humblehomemadehifi.com/Cap.html.

They come in many flavors and their sound will vary with the synergy in your system and listening room. I am a relatively new owner of a pair of monitor 10A with the US made Peerless tweeters. My speakers have original crossovers. I would not describe the sound as you have with your set.

There are several types of peerless tweeters used in the early monitors. Depending on the detail of the picture some of the old time experts on this forum can identify the type from a picture of the front of the tweeter, but if you crack these open this weekend, take a picture of the back of the tweeter also and post.

Same with the crossovers. Take pictures and you will find help!

There are tons of tweaks and upgrades if you use the search to get the best sound possible out of these speakers. There should be no reason for these not to be keepers, they may just need a little help getting there.

geppy1

I need to see apicture of the front and back of the tweeter. One thing that can happen is the VC can get misaligned. It can be reset. I suspect your problem is in the crossover. Did you check the fuses?? I am just guessing though.

skrol

I have a pair of Monitor 5A form 1983 with the Peerless tweeters. I also have a pair of RTA11TL with the RDO198 upgrade. I can say that the two speakers are voiced very similar on the mids and highs.

I attached a schematic diagram of my Monitor 5A crossover. I am not certain of the inductor values but the caps and resistors are correct.
Stan

kjm531

I'll post some pictures and information this weekend.

Thanks for the info so far. What a great forum this is...
Looking forward to getting these to their full potential!

kjm531

Ok I got some free time tonight.
Here are some pictures...

The 'BP' piece on the crossover is a 33uF

skrol

I have seen those resistor values used in Monitor 5s. I may be wrong but I thought that it was with the SL1000 tweeter. Polk did a lot of tweaking of components in those days. It is not much of an upgrade on the crossover. It looks like they changed the 12uF electrolytic for a Bennic metalized polypropylene film capacitor but kept the 33uF electrolytic.

Do you know what year yours were made? Also, How much Daycron damping material is in your cabinets? Mine are really stuffed, even behind the PR which I thought was a no no. I also found a lot of excess cabinet glue fragments from when they were manufactured floating around inside.

Stan

kjm531

Stan, Thanks again for the information.

The guy I bought them from said these were his first crossover redo. He bought the kit off ebay and mentioned that after researching a bit more, he probably paid way too much for it as compared to just buying from Parts Express or something.

You are exactly right on the stuffing! When I took the picture of the crossovers I noticed it was packed all thru out the cabinet. I checked my 7C's and there was only stuffing up near the tweeter.... not behind the mid or PR. I took most of the stuffing out but haven't had a chance to listen yet to see if it makes a difference.

What are the best caps to use for these? Seems like it may be worth redoing them at this point. Also, do most of you guys redo the internal wiring and connections while doing the x-overs?

Thanks again,
Kevin

kjm531

Well, I finally had a chance to do some listening for a few hours today and I'm starting to think maybe this is the way these are supposed to sound.
I sold my 7C's this past week so I don't have a direct comparison to other Monitor line speakers but I picked up a PSB subwoofer and 400i bookshelf speakers. So I had a 3 way comparison between the 5A's, 400's and Ascend CBM-170. The PSB and the Polk are so close in sound I doubt I could tell one from the other if blindfolded. They both sound good, but the Ascend speakers are so detailed in the mid to upper range that it was as if a veil had been lifted in front of the speakers. Without a sub, I don't think I could live with them... there is no 'weight' to them, but with the PSB sub they are incredible.

Anyway, sorry for the false alarm. I guess I was expecting a bit more out of the Peerless tweeters.:redface:

skrol

I had used Clarity Cap PX in my RTA11TL crossovers. It made a very nice improvement in the sound stage. Another good one would be the Sonicap.

If I keep my Monitor 5A's, I'll probably use the Clarity Caps again.
Stan

skrol

A note on the internal wiring. I was cautioned my a friend who used to be a design engineer for Polk Audio, that the speaker is voiced with that wiring (wire resistance). If you change the wire by going to a different gauge then the voicing will change. He extended this warning to the inductor ESR too.

Stan