X-Over for B139/B110/HF2000/STC-4001G or IMF TLS-80 vs RSPM4

[jimmymcfarre]

Just fishing for opinions here really:
Thinking about re-capping the x-overs in my IMF RSPM4s & it's got me thinking - I really don't need all the adjustment capabilities of these x-overs, having such a complicated circuit can't be good for outright sound quality & must be quite inefficient and I've read of several people preferring the sound of the TLS-80s to the RSPM4s, saying they're more involving and direct sounding. The cabinet size of the two IMF models is virtually the same - the RSPM4 is an inch wider & 3/4" deeper and I'm assuming it's height increase is due to the x-over being housed in the base. The TL opening on the RSPM4 is above this which makes me think the actual length of the line in the two models is the same. This does however contradict the fact that the frequency response of the RSPM4 is greater: >17hz vs >20hz for the TLS80. So either the RSPM4 goes a bit lower because of it's slightly larger transmission line, or the x-over itself is responsible.
So,working on the assumption that the two models are the same, or certainly so similar as to mean any differences are due to the x-over, and the TLS-80 is a better home hifi speaker - I'm not saying it's technically better, certainly not on paper, but the general idea I get from reading on the net is the the TLS-80 is a bit more fun and involving to listen to, as it sounds less like listening to a piece of lab equipment and my thinking is that this must be down to the less complicated x-over. So i reiterate, I'm not saying the TLS-80 is better, I'm guessing it's ultimately less accurate, however as a consequence to this, it sounds more fun (having not heard the 80s I'm fishing for opinions). Because of this I'm contemplating building TLS-80 x-overs out of new caps for my RSPM4s instead of recapping the original ones. I'll do it in such a way that it can be reversed and thinking it'll give me the best bits of both models - if there are any advantages of the RSPM4 cabinet size I'll still benefit from them, with the added musicality of the simpler TLS-80 x-over. They'll cost less to build and as I'll be building them from scratch i can hard wire them. This sounds to me like a win win situation all round, given the fact that these speakers are only used as for domestic listening, however as all modifications will be reversible I don't see there being any downside to this...
Any thoughts....?

 

[canuckaudiog]

Just fishing for opinions here really:
Thinking about re-capping the x-overs in my IMF RSPM4s & it's got me thinking - I really don't need all the adjustment capabilities of these x-overs, having such a complicated circuit can't be good for outright sound quality & must be quite inefficient and I've read of several people preferring the sound of the TLS-80s to the RSPM4s, saying they're more involving and direct sounding. The cabinet size of the two IMF models is virtually the same - the RSPM4 is an inch wider & 3/4" deeper and I'm assuming it's height increase is due to the x-over being housed in the base. The TL opening on the RSPM4 is above this which makes me think the actual length of the line in the two models is the same. This does however contradict the fact that the frequency response of the RSPM4 is greater: >17hz vs >20hz for the TLS80. So either the RSPM4 goes a bit lower because of it's slightly larger transmission line, or the x-over itself is responsible.
So,working on the assumption that the two models are the same, or certainly so similar as to mean any differences are due to the x-over, and the TLS-80 is a better home hifi speaker - I'm not saying it's technically better, certainly not on paper, but the general idea I get from reading on the net is the the TLS-80 is a bit more fun and involving to listen to, as it sounds less like listening to a piece of lab equipment and my thinking is that this must be down to the less complicated x-over. So i reiterate, I'm not saying the TLS-80 is better, I'm guessing it's ultimately less accurate, however as a consequence to this, it sounds more fun (having not heard the 80s I'm fishing for opinions). Because of this I'm contemplating building TLS-80 x-overs out of new caps for my RSPM4s instead of recapping the original ones. I'll do it in such a way that it can be reversed and thinking it'll give me the best bits of both models - if there are any advantages of the RSPM4 cabinet size I'll still benefit from them, with the added musicality of the simpler TLS-80 x-over. They'll cost less to build and as I'll be building them from scratch i can hard wire them. This sounds to me like a win win situation all round, given the fact that these speakers are only used as for domestic listening, however as all modifications will be reversible I don't see there being any downside to this...
Any thoughts....?

Hi there,

I have owned both the TLS 80 II and the RSPM Mk IV at the same time in the past.

My findings are nowhere near similar to anyone who felt the TLS 80 was better than the RSPM Mk IV. The Mk IV, to my ears, sounds much better. Cleaner, with better presentation of detail, less distortion, more full bass, better separation of instruments, etc. I never found the TLS 80 II to be more "fun" to listen to. The Mk IV is not clinical or critical sounding to my ears. The Mk IV is, however, pickier about its upstream electronics and placement in comparison, but not by a terrible amount. If yours are all original though, you may find them boring to listen to as I did before I recapped mine. They will improve substantially after doing so.

I think you are barking up the wrong tree, so to speak, because I have thought much the same that the controls simply overcomplicate the crossover. However if you aren't using the controls, they are switched out of the circuit and should have no impact on the sound quality (as far as I know, anyway). I suggest replacing the capacitors and not bothering with trying to modify anything, it's going to end up giving you a pair of modified speakers that will lose value and likely you will not gain much, if any benefit from it. My Mk IVs have been recapped using the Falcon Acoustics kit and sound phenomonal.

Anyway, from my experience on owning both models, the RSPM Mk IV is more musical and definitely more engaging than the TLS 80 II. The gentleman I sold the TLS 80 IIs to has come over and listened to my Mk IVs and confirms that, although that is a bit of a stretch considering the Mk IVs are on totally different electronics and in a different room. Either way, I think your best plan is to simply recap the Mk IVs and take it from there.

Edit: I think the only main difference between the two is the Mk IV has bypassed mylar film capacitors on all of the electrolytics. The inductors could also be of higher quality, with thicker gauge wiring and lower DCR. This is about all I can find and would be a fair reason for why the Mk IV sounded better to my ears. FWIW, both the TLS 80 IIs I owned and the Mk IVs were recapped when I compared both.

 

[SimplySound]

I haven't heard either, but if you can build up some X-Overs without damaging/destroying the originals, why not try it? Everyone's hearing and preference is different, so what Canucker may have found with his comparison may not match your experience.

That's one thing I've learned about this hobby, is you never really know if something will work or if you'll like it until you hear it!

Makes it "bloody" expensive too if you start really playing around. But if you have the time and inclination go for it....

And be sure to let us know what you find out!!! :thmbsp:

 

[JimPA]

I would use the exact same inductors as the original ones used if I were to build a new crossover.
Using an inductor with a different dcr will effect the driver Qts. and the response of the T-line will be altered by this.

 

[jimmymcfarre]

I would use the exact same inductors as the original ones used if I were to build a new crossover.
Using an inductor with a different dcr will effect the driver Qts. and the response of the T-line will be altered by this.

True, although what we are talking about here are two speakers with the same drive units (although should it be hf1300 / hf2000 not as i thought hf2000 / stc4001g, i think) in, to all intents & purposes, the same cabinet and where the only obvious difference is the inclusion of a load of filters that i don't use. Building both would be interesting - i wonder if I'd recoup the cost of the parts by selling the loser crossover on afterwards....

 

[mech986]

OP, what did you decide to do with your crossovers?

 

[Yvan_donald]

HI, to everyone Jimmi use a x-over from prof.MkIV non Rspm ,the regular model and about The Tls 80 Mk -Mk II, because of cabinet size (smaller), the midranges or /and the woofer at high volume was going true the tube (midranges enclosure).that is a problem with thickness and the way it's insulate, that's probably why they change on Mk VII to insulate more the drivers, best regards, Yvan

 

[Yvan_donald]

HI, I have crossover's for Mk IV complete not RSPM,Yvan

 

[Yvan_donald]

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